Annals of the Sri Lanka Department of Agriculture ASDA 2016

VOLUME 18

EDITORS

Gamini Pushpakumara Buddhi Marambe Pradeepa Silva Lalith Suriyagoda Ranjith Punyawardena Priyantha Weerasinghe Wijayasiri Weerakoon 2016

Department of Agriculture Ministry of Agriculture Sri Lanka

The responsibility for this production rests with the Department of Agriculture, Sri Lanka (DOASL).

All rights reserved. Except for quotation of short passages for the purpose of criticism and review, no part of this publication may be reproduced, stored in retrieval systems, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior permission of the Director General of Agriculture. The DOASL does not require payment for the non-commercial use of its published works, and hopes that this copyright declaration will not diminish the bona fide use of its research findings in agricultural research and development.

Annals of the Sri Lanka Department of Agriculture. 2016. Volume 18. © Department of Agriculture, Sri Lanka.

ISSN 1391 - 6947

This book was prepared on the desktop publishing system at the ASDA Secretariat, P.O. Box 21, In-Service Training Institute, Department of Agriculture, Gannoruwa, Sri Lanka and printed by the Publication Unit of the Department of Agriculture, Peradeniya, Sri Lanka.

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CONTENTS

FOREWORD ...... xv Full Papers of Research Articles in Extended Abstract form are Available in the Volume 164 of “Tropical Agriculturist”. Glycemic index of improved rice varieties as influenced by degree of polishing and proximate composition including amylose content R. F. Hafeel, L.B.A.P. Amararathna, T.H.T. Chamintha, A.P. Bentota, D.S.De Z. Abeysiriwardana, S.K.J. Muhandiram and B. Perumpuli ...... 1 Long term application of organic manure and chemical fertilizers on rice productivity and fertility in paddy growing soils in Kurunegala district D.N. Sirisena, W.M.N. Wanninayake and A.G.S.D. Silva ......

Determination of effect of cooking on total polyphenol and ascorbic acid 6 content and antioxidant activity of five common green leafy vegetables and curry leaves S. M.A.C.U. Senarathne, D.K. Wijerathne, K. W.P.D. Karandawala and K.H. Saranada ......

Transmission and host range studies of Sri Lankan isolate of chilli veinal 9 mottle virus in chilli C. Ranasinghe, B. Dharmarathna, R.T. Ekanayake andS. Geethika ...... Combining ability, heritability and gene action analysis of yield and some 13 yield contributing characters in chilli ( Capsicum annuum L.) inbred lines H.M.S.N. Herath, H.M.S. Bandara, W. G. Wijepala and H.M. Karunarathne ......

Toxic trace elements in vegetables collected from markets in Kandy district 16 N.R.N. Silva, P. Weerasinghe and H.D.K. Rathnapriya ......

Morphological and molecular characterization of Trichoderma isolates used 19 as bio-control agents in Sri Lanka R.G.A.S. Rajapakse, F.S. Fariz, W.A.R.T. Wickramarachchi, D. M.K.K. Dissanayake, M.P.T. Premarathne and K.J.P.K. Kahawatte ...... Seed borne pathogens associated with seed lots of major food crops of Sri 23 Lanka

M.G.D.L. Priyantha, A.R.J. Athukorala, J.A. V.J. Jayasinghem, M. Sato and H. Takahashi 26

Performance of Bw rice varieties grown in three different soil types in the wet zone of Sri Lanka W.R.K.D.W.K.V. Wickramasinghe, S.P. Gunarathne, D. M. Jayasundara, H.A.I. Sajeewani, K.D.S. Samararatne and J.B.K. Kannangara ...... 28

Diversity and correlation among agronomic traits in newly improved rice varieties under drilling and random broadcasting T.K. Illangakoon, J.M.N.P. Somaratne, S.S. Paththinige, R. S.K. Keerthisena, C.H. Piyasiri, S.D. Abeysundara 31 and I.H. Thushara ......

Income diversification among member’s of farm women organization in Ampara district A. T. Sooriyaarachchi, R.A.K. Kalyani and H...... U 34 . Waranakulasooriya ......

A promising multiplier onion (Allium cepa) line with field resistance to major fungal diseases and possessing moderate flowering efficiency S. J. Araskesasry, B. Bowleeswaran, P. 37 Atputhachandran, S. Hear and B.G.R.C. Balasooriya ......

Effect of natural and artificial diets on the life history parameters of melon-fruit fly, Bactrocera cucurbitae (Diptera: Tephritidae) 40 P.H. Ranaweera, L.D. Galaniha, M. Ranathunga, K. M.D. W. P. Nishantha, M. Siriwardana and L. Nugaliyadde ......

Development of a ready to serve “Embul” banana beverage as a value added product 43 R. A.A. Ranathunga, G.T.N. Gunasekara and W.A.K. Karunathilaka ......

Effect of different Psidium rootstocks on the control of root knot nematode and growth and yield of guava (Psidium guajava L.) 46 E. R.S.P. Edirimanna, R.G.A.S. Rajapakse, A. 50 Weerawarna, S. Pushpakumari, B. G. Amrasena and T. Kirinde ......

Genetic variability, phenotypic and genotypic correlation and path coefficient analysis of black gram (Vigna mungo (L.) Happer) M. J.M.P. Kumararthana, A.T. Sooriyararchchi and 53 R.R.P.S. Ariyawansha ......

Assessment of the temperature regime in agro ecological regions of Sri Lanka A. B. Abeysekera, B.V.R. Punyawardena, A. K. Hettiarachchi, E.V.G.N. Jayarathna Banda and K.H.M.S. Premalal ......

Micro propagation of new anthurium varieties: Lanka Beauty and Lanka Kumari R.N.I. Perera, R.G.A.S. Rajapaksha, W.M.E.K. Bandaranayake and D.A. Samarasingha ...... 56 pollen fertility in different rice varieties L.C. Silva, M.S. Nijamudeen, H.G.P.B. Dharshana W.M. W. Weerakoon and P. Mahindapala ...... 61

Need based nitrogen management of maize (Zea mays L.) grown in the dry zone of Sri Lanka using a six panel leaf colour chart K.A. Renuka and W.M.I. Senavirathna ...... 64 Performances of different breeding methods based on the estimated genetic parameters in f4, f5 and f6 generation advancements of cowpea (Vigna unguiculata (L.). Walp) M. C. Millawithanachchi, V.A. Sumanasinghe, A.B. Bentota, B.N. Samaranayake and N. T. Prathapasinghe ...... 58

Soil moisture depletion and its influence on raising spiklet temperature and Occurrence of anthracnose (Colletotrichum gloeosporioides Penz.) and rust (Goplana dioscoreae Cummins) diseases of Dioscorea in Sri Lanka W.A.P.G. Weeraratne, N.L.A.T.S. Nanayakkara, A. D. Anushika and D.D.D. Darmadasa ...... 68

Estimation of phenotypic diversity of chilli (Capsicum spp.) germplasm in Sri Lanka B. M.K. Senarathne Menike, W.M.R. Kumari, H.M.S.N. Herath and H.M.S. Bandara ...... 70

A promising early maturing, confectionary type groundnut (Arachis hypogaea L.) variety well adaptable to local cropping systems in Sri Lanka Y.P.J. Amarasinghe, D.G.C. Jeewani, M.T. Gunasena, W.M.P.N. Dilusha, R.A.A. Ranatunga, G. Wijesinghe, G. T.N. Gunasekara and R. W. Pushpakumara ...... 74

Assessment of genetic diversity among suwandal rice (Oryza sativa L.) accessions based on morphological, molecular and physicochemical characteristics S.K. Wasala, H.M.K.N.K. Hennayake , P.G.S.D. Gunasena, S.P. Rebeira, K.M.C.L. Kondasinghe, 78 A.S.J. Danwatta and N.M. Ubeysekara ......

Effect of different water regimes on yield and water use of red onion (Allium cepa ) grown under non-calcic brown soils ( haplustalf) in the low country dry zone of Sri Lanka A.G. Chandrapala, S.H.S.A. De Silva and N.D. Ranawaka

Effect of irrigation intervals on growth and yield of cluster onion in non-calcic brown soils D.G.P.S. Delpitiya, S.H.S.A. De Silva, R. A.C.J. Perera, P.G.T.L. Madumali, H.A.P. Jayalath and W.M.D.N. Weerasinghe ...... 85

Effect of fungicides on management of fungal bulb rot in cluster onion M. S.W. Fernando, S.H.S.A. DE Silva, B. Bawaleeswaran, S. Kanchana andR.M.C. Sudumanike ...... 88

Popularity assessment of recommended rice varieties in Sri Lanka D.M. Withanawasam and N.L. Sudheera ...... 92

Molecular breeding for improvement of blast and sheath blight resistance in Sri Lankan rice cultivar ‘Pokuru Samba’ D.S. Kekulandara, K.R.D. Gunapala, N. S. Thilakarathne and K.A. G. Deepika ...... 96

ANKCP 01: a new cowpea (Vigna ungiculata (L.) Walp.) variety for cultivation in dry and intermediate zones of Sri Lanka B. N. Samaranayake, M.C. Millawithanachchi, N.T. Prathapasinghe and R.A.A. Ranathunga ...... 99

Effect of soil conservation measures on soil erosion, soil moisture and crop productivity in the mid country intermediate zone of Sri Lanka A. G. Chandrapala, K.M.A. Kendaragama and T. M.N.D. Kumarihamy ...... 102

Effect of dry heat treatment on physicochemical parameters of coir and eradication of Fusarium solani M.H.A.D. Subhashini, C. Gamage andK.S.I. Senavirathna .... 105

Performance and adaptability of new yard-long bean variety: Gannoruwa A9 Mae P. Malathy, W.D.G.P. Nilanthi, E.M.N.T.M. Ekanayake, W.A.R.T. Wickramaarachchi andK.H. Sarananda ...... 108

Management chilli veinal mottle virus in chilli using Pseudonomas fluorescence C. Ranasinghe , P.M. Mallikaarachchi , D. M. Gunasekera and V. Navagamuwa ...... 111

Integrated soil management approach to enhance the growth and yield of chilli ( Capsicum annum ) H.M.P.T.K. Hettigedara, M.A.P. W.K. Malaviarachchi, R.A.C.J.Perera,W.M.W. Weerakoon, S.P. Nissanka, U. R. Sangakkara and G.H.K. De Silva ...... 115

Management of maize stem borer Chilo partellus Swinhoe (Lepidoptera: Pyralidae) using selected plant powders with insecticidal properties K. N. C. Gunewardena, I.P.S.D. Wickramasooriya and K. P. Jayanthi ...... 118

Critical period of weed control in big onion (Allium cepa L.) under two different agro-ecological zones of Sri Lanka D. P.P. Liyanage, D.R. Wenaka, D.L. Wathugala, H.R.C. Niroshani and D.S. Yapa ...... 121

Effect of 1-methylcylopropene (1-MCP) on postharvest quality and shelf life of okra H.R.P. Fernando, M.R. Prasangika and W. G. B. R. Ariyaratne ...... 125 Induced flowering with artificial light for year round production of dragon fruit in Sri Lanka S.A.S.M. Kumari, M.A.D.K. Mannanayake, W.M.S. Warnasooriya M.A.L.R. Munasinghe and K.N. Kannangara ...... 128 Assessment of genetic variability in recombinant inbred lines of chilli (Capsicum annuum L. ) H.M.S.N. Herath, W.M.W. Weerakoon, B. Marambe, A.M. Pereara , J.M.J.B. Senanayake, H.M. S. Bandara ...... 132 Short Communication

Seedling dipping as a method for phosphorus fertilization in rice grown under phosphorous-deficient soils using parachute transplanting W. R. K.D.W.K.V. Wickramasinghe, S. P. Gunarathne, K.D.S. Samararathne and K.K.D. Chandrasekara ...... 135 Evaluation of fruiting ability and fruit quality through different training systems of apple E. K.E.C. Nayana, D.M.R. Dassanayake, Y.L.B. Paviththrani andM.A.L.N. Mallawaarachchi ...... 139 Assessment of most popular three months age rice varieties for zinc (Zn) accumulation in brown rice D.N. Sirisena, W.M.N. Wanninayake, S.S.S. Weralugolla and A.G.S.D. Silva ...... 144 Influence of varietal differences on sensory qualities of local rice-based food products R. J. Rathnayake, D. K. Padmalatha and K.M.K. Kumarihamy ...... 148

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Validation of agricultural production systems simulator model for mung bean [Vigna radiata (L.) R. Wilczek] in the dry zone of Sri Lanka C. Ranasinghe, M.G. Gunasena, B.M.V.S. Basnayake, W.M.N.D. Gunathilaka, R.P.R.K. Amarasingha and U.I.P. Perera ...... 152

Assessment of pesticide usage in leafy vegetable farming in Matara district G. C. Prasadi and D.L. Wathugala ...... 156

Evaluation of finger millet germplasm for resistance to blast caused by Magnaporthe grisea W.M.K. Fernando, H.N.S. Fernando, W.M.S.D.K. Wijerathne,D.M.K. Dissanayake, W.M.R. Kumari and D.C.M.S.I. Wijewardana ...... 161

Efficacy of ethyl formate (16.3 % w/w) in liquid carbon dioxide (83.7% w/w) as a fumigant for the control of mealy bugs in pineapple and pests of stored rice and maize I. K. Warshamana, P.R.A. Wijesinghe, G.T.S. Perera, T. N.P. Fernando, S.M.A.C.U. Senarathne, S.S. Weligamage H.M.R. Bandara, T. Swaminathan and L. Nugaliyadde ...... 165

Effects of plant density and cultivar on geometrical properties of bulb and bulb yield of cluster onion (Allium cepa L.) H.M.C. Hitinayake, J.P. Sumanarathne, M. G.N. Madhushika, W.A.D.S. Abeysekara and K. G. Swarnalatha ...... 169

Efficacy of carbosulfan 200 g/l SC and diazinon 500 g/l EW for the management of paddy bug (Leptocorisa oratorius) in Sri Lanka S.R. Sarathchandra, D.T.B. Perera, A.S.K. Abeysekara S. Wickremasinghe, U.C. Kahawatta and L. Nugaliyadde ...... 173

The effect of flowering plants to enhance natural enemy population in paddy fields M. A.R.A. Mandanayake, M.G.D.L.Priyantha, A.P.Bentota,U.G.A.I. Sirisena, A.M.K.R. Bandara, U. C. Kahawaththa ...... 177

Evaluation of rice lines for drought tolerance during reproductive and grain filling stages T. K. Illangakoon, J.M.N.P. Somarathne, S.S. Paththinige, C.H. Piyasiri, R.S.K. Keerthisena, A. P. Bentota, U.A.K.S. Udawela, W.M.W. Weerakoon and B. Marambe 181 Application of hot air as a de-vitalization treatment for weed contaminant in coir and coir based products L. D. K. Arachchige, D.P.P. Jayakody and

D...... I.M. Amararathna ...... 186

Determination of effective yield increment of salad cucumber (Cucumis sativus) with supplementary lighting H.R.U.T. Erabadupitiya, R.S. Wijesekara and D.M.N.H. Jayasekara ...... 191

Comparison of two types of mushroom-growing houses for mushroom production, environment conditions and insect abundance P. Rajapakse, N.P. W. Jayarathna, N. V.A. Manjula and D.D.E. Piyathissa ...... 195

A simplified nutrient film technology (SNFT) for seed potato production J. M.D.D. Jayamanna, S.M. U.I. Samaraweera and C. D. Jayasinghe ...... 199

Property right value estimation of paddy varieties produced by the department of agriculture K. G.C.D.B. Wijesinghe, V.D.N. Ayoni and T.H.C.S. Perera ...... 204

Screening of chilli (Capsicum annum L.) parental lines for chilli leaf curl virus, bacterial leaf spot and anthracnose diseases W.M.K Fernando, W.M.S.D. K. Wijerathne, D. M.K. Dissanayake and H.M.S.N. Herath ...... 207

Investigation on brown spot disease of rice (Oryza sativa L.) in Sri Lanka H.N.S. Fernando, Y.J.P.K. Mithrasena, J. N.Silva and A.A. W.P.Adikari ...... 212

Heavy metal contents of composts made using different raw materials S.P. Gunarathne, G.A.S.S.L. Gunathilaka, K. A.C. Kandemulla, B.K.Kannangara, K.K.D. Chandrasekara, A.E. Munasingha and S.D. Umange ...... 216

Effectiveness of black soldier fly larva (Hermetia illucens) in solid waste management and kitchen waste composting D.M.P.S. Dissanayake, G.D.R. Silva, W.J.S.K. Weerakkody,K.A.C. Kandemulla and H.M.S.K. Herath ...... 220

Capsicum spp. H.M.P.S. Kumari, H.M.S.PK. Herath, Menaka Jayathilaka, E.P Wijewardhana, Iroshani, S. Kahadawaarachchi ...... 229

Submergence tolerant rice line for flood prone areas in Sri Lanka M.G.N. Rupasinghe, W.L.G. Samarasinghe and K.M.S. De Silva ...... 233 Effect of root pruning and re-potting after grafting on grafting success, shoot and root growth and survival percentage of durian (Durio zebethinus Murr.) E. R.S.P. Edirimanna, K.M.M.T.U.B. Kangara, W.T.P. Wicramarathne and H.A.K.N. Hettiarachchi ...... 224

Development of embryo rescue technique for wide hybridization of Effect of minimum temperature fluctuation during dormancy period on total harvestable yield of pear (Pyrus pyrifolia) in up country intermediate zone of Sri Lanka Y.L.B. Pavithrani, C.J. Karunarathne and K.P. Somachandra ...... 237

An action threshold and a fungicide spraying schedule for rust and angular leaf spot in bean E. A.E.S.S. Jayasekara, K.P. Somachandra, W.M.S. Gunasekara, K.K.N.N. Gunawardhana and G.A.R. Somasiri ...... 241

Relative weed competitiveness ability of some selected BW rice varieties in low country wet zone, Sri Lanka W.R.K.D.W.K.V. Wickramasinghe, D.C.M. Paranagama, 245 M.K. Kurulugama and S.D. Umange ......

Impact of usage of agro-chemicals on soil bio diversity in vegetable fields at Mandaram Nuwara in Nuwara Eliya district R. G.S. Iroshani andK. Mohotti ...... 250 systems of apple E.K.E.C. Nayana, D.M.R. Dassanayake, Y.L.B. Paviththrani and M.A.L.N. Mallawaarachchi ...... 254 Mophometric evaluation of exotic and local rice hybrid W.S. Priyantha, D.M.O.K.B. Dissanayake and D.M.N.D. Dasanayake ...... 259

Evaluation of fruiting ability and fruit quality through different training

Response of rice and weeds to early submergence in direct seeded rice in Sri Lanka H.M.S Herath, R.F. Hafeel, R.S.K. Keerthisena and A.P. Bentota ...... 265

Posters

Development of a spicy snack from egg fruit (Lavulu) Pouteria campechiana (Kunth) Baehni M. Bulathkandage, R. Henadeera and M.H.R.M. Jayapala ...... 270

and Y.M.S.H.I. U. De Silva ...... 272

Study on the effectiveness of game based learning for paddy farmers in Galle district S.H. Kahingala ...... 273

Morphological characterization of Gerbera jamesonii accessions N.B.U. Dissanayake ...... 274

Banana leaf roller, a new pest to Sri Lanka K.A.J.C. Premawardhane, H.K. Kumuduni, W.M.C.N. Wijesinghe ...... 275 Evaluation of machine transplanting with conventional establishment methods of rice R. M. U.S. Bandara, A.S.K. Abeysekara, S. G. Dombagolla, W.M.U.B. Wickrama and Y.M.S.H.I.U. De Silva ...... 271 Environmental impact assessment of herbicides used in rice farming in Sri Lanka R.M. U.S. Bandara, A.S.K. Abeysekara, H.M.S. Herath, S.R. Sarathchandra, L. A.D.S.Wijesinghe, W.M.U.B. Wickrama, H.M.M.K.K.H. Dissanayaka, D.M.C.B. Dissanayake Bee colony fence: an eco friendly and sustainable bio fence for rescuing agricultural lands from raiding elephants (Eliphas maximas ) S.K.N. Rubasinghe ...... 276 Development of a novel candy using calabash gourd (Lagenaria siceraria (Molina) Standley) D.N. Hettiarachchi, K.H. Sarananda, S.T.J. Bandara and C.K. Ranawana ...... 277 Seedlings treated with P fertilizer to save fertilizer in rice cultivation D.N. Sirisena and W.M.N. Wanninayake ...... 278

Assessment of socio economic impact of Weligama coconut wilt disease: a case study Weligama DS division G...... C. Prasadi and N.S. Liyanapathirana ...... 279

Fruit bagging technique for improving the fruit yield and quality by reducing fruit fly damage in rose apple A. S. Pushpakumari and M...... G.N.E. Mahagollage ...... 280

Molecular detection of pineapple mealybug wilt associated virus-1 and virus-2 by using duplex PCR method T.M.N.D. Tennakoon, G.M C. Nuwanthi and K.D. Nandasena ...... 281

Introgression of sub 1 gene into some popular improved rice varieties and performances of derived breeding lines N. P.S. De Silva, G.D.A. Priyantha, K.S. Udawela, W.L.G. Samarasinghe, K.A.C. Rasanjali, J.P. Baruhupola, B.G.D.S. Weerasinghe And A.P. Bentota ...... 282

Low cost, low weight alternative potting media for fruit planting material production S.T. Baddegama, B.L.D.L.D. Wijesundera and D. Harshani ...... 283

An improvement of blb resistance in ld 99-12-38 by marker assisted backcross breeding W.D.P Weerasinghe, Kapila Siri Udawela and H. A.M. Wickramasinghe ...... 2 8 4 Micropropagation of Diascorea alata (var. rajaala and kekulu): an alternative to conventional planting materials R.N.I. Perera, N.L.A.T.S. Nanayakkara, W.M.E.K. Bandaranayake and D.A. Samarasingha ...... 2 8 5 Relationship between climatic factors, flowering and fruit set of Asian pear ( Pyrus pyrifolia ) E.K.E.C. Nayana, D.M.R. Dassanayake and M.M.U. De Silva ...... 286 Application of paclobutrazol for flower induction of durian (Durio zibethinus Murr.) W.D. Lesly and J.A. C.D. Jayasinghe ...... 287

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Weed floral diversity under intensive rice cultivation at Rice Research Farm, Batalagoda R.M.U.S. Bandara, A.P. Bentota, R. S.K. Keerthisena, D.N. Sirisena, A.S.K. Abeysekara, S. S. Paththinige, M.A.R.A. Mandanayaka, S. R. Sarathchandra, R.D.M.G. Wijethilaka, W.M. U.B. Wickrama, H.M.M.K.K.H. Dissanayaka, D.M.C.B. Dissanayake and Y.M.S.H.I. U. De Silva ...... 288

Assessment of the possibility to increase nutrient uptake in red onion (Allium cepa L.) with different nutrient alternatives in Kalpitiya sandy regozol soil D.M.P.S. Dissanayake, P. Weerasinghe, T. S. Jayathilake, W.J.S.K. Weerakkody and K.A.C. Kandemulla ...... 289

Threats to durian trees ( Durio zibithinus ) and their management in Gampaha district I. K. Atapattu, M.L.L.C. Mahanada, D.S.K.P. Dewage and R.P.K.C.Rajapakse ...... 290

Seedling emergence & early seedling growth of Tomato (Solanum lycopersicum L.), Brinjal (Solanum melongena L.) and Capsicum (Capsicum annum L.) on nursery beds covered with colour polythene H.M.V.T. Welegama, D.M.S.M. Dissanayake R. M. Fonseka, D.A. U.D. Devasinghe A. M.D.A. Abeysekara, H.C. Rambukana and H. Fonseka ...... 291

Effects of high temperature stress affecting chilli (Capsicum annuum L.) cultivation in Sri Lanka B. M.K. Senarathne Menike, H.M.S. Bandara, A.M. Karunaratne and S. M.N.I.K. Saluwadana ...... 292

The “permanent crop clinic programme” in Sri Lanka: making use of data to resolve crop health problems. M.U.P. Jayasundara, Y.M.C.K. Herath, A. N. Abeykoon and K. Cameron ...... 293

Protein and micro nutrient contents of selected rice varieties grown in different agro-ecological regions in Sri Lanka. S.P. Gunarathne, K. V. Wickramasinghe, B. K. Kannangara, K.K.D. Chandrasekara, A.E. Munasingha N.M.L.D.Nagasena, D.M.S. Duminda, C.H. Piyasiri, H.M. C. Hitinayake, L. C. Silva, D.M. Withanawasam and Y.B. Iqbal 294

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Jewel beetle (Sphenoptera indica); a new pest of groundnut in the northern province of Sri Lanka S. Rajeshkanna, S. Mukunthini, T. Jogeswaran and L. Nugaliyadde ...... 295

Potential use of plant growth promoting rhizobacteria to manage papaya rings spot virus in papaya C. Ranasinghe, D.M. de Costa, V.S. Basnayake, D. M. Gunasekera and S. Priyadharshani ...... 296

Callus induction and plant regeneration in pomegranate ( Punica granatum L.) using leaf explants L.G.I. Samanmalie, S.B.A. Weerawarna, Anoma Rohini and K. G. G. Indika ...... 297

Post evaluation observations of the national programme on fruit tree pruning and rehabilitation V.D. Nirusha Ayoni and T.H.C.S. Perera ...... 298

Use of power weeder to thinning out broadcasted seedlings as a transplanted rice cultivation A.H. Priyantha Rajakaruna and D.M.S.B. Dissanayaka ...... 299

List of Reviewers ...... 299

Instructions to Authors 306

FOREWORD

The Editorial Board take pleasure in presenting Annals of the Sri Lanka Department of Agriculture 2016 (ASDA-2016) for the eighteenth consecutive year, Volume 18, in which the research articles make it a rich source of information that will prove to be of great value not only to the scientific communities and decision makers who will give direction and guidance for sustainable agricultural development of the country but also to business and farming communities and consumers. In this year, the peer reviewed journal attracted 123 research papers, submitted by the scientists of DOA, of which, based on rigorous review process, 41 research papers and 31 short communications were accepted for publication based on quality of papers with scientific merit. The broad themes of papers include food science, agronomy, land and water management, socio-economics, plant breeding, plant pathology, entomology, soil science, and bio-technology. The Annals also included 30 abstracts of posters.

The Annals provides a glimpse of the present situation with regard to research activities of DOA and where we are heading. In Sri Lanka, as elsewhere in the world, technical improvements, resulting from significant contribution made by the researchers of DOA have substantially increased the agricultural productivity of the country, and also made the pathway to self-sufficiency in rice and maize. The DOA being the key player in the crop production segment of agriculture has now need to proactively consider the challenges that may arise in agriculture in the current phase, given the radical changes that occurred in the post war development period of the country. Further, global development aspirations have changed from sole economic growth to sustainable development. This requires concomitant growth in agriculture productivity and the conservation of environment and natural resource base upon which the sustainability of agriculture depends.

However, agriculture in Sri Lanka and elsewhere is highly vulnerable to changing climate on one hand and the promotion of unrestricted international trade of agricultural commodities from the other hand. Hence, challenges for future agriculture will be much greater than the present. In addition, the DOA declared the “white revolution” in agriculture. These national and global changes, impacts of agriculture on environment and new conceptual thinking offer a greater potential for new avenues and are associated with problems that impact nation, its economic sector, social institutions and individuals differentially and need to inculcate in future research and development endeavours. Developing the human capital with skills and knowledge in the field of agriculture is one of the best alternatives to achieve robust and sustained growth in the agriculture sector

16 and to facilitate its adaptation to environment, economic and social changes. We, as editors of the Volume 18 of the Annals are optimistic that process and outcomes of this volume will help to create an innovative research culture and build up a new paradigm in agricultural development in Sri Lanka. We also hope that this process will stimulate logical thinking in conducting research and critical thinking on data analysis. We sincerely hope that the process of ASDA would no doubt support to enhance a research culture of the DOA and also supportive of publishing of information and implementation of their outcomes in the field of agriculture in salient, credible and legitimate manner. Full papers of research articles in extended abstract form are available in the Volume 164 of the “Tropical Agriculturist”, the oldest Agricultural Journal in Asia.

The editors wish to thank the researchers and paper reviewers for prompt response and friendly cooperation extended. The untiring efforts of the members of the ASDA Secretariat, ADA and the staff of the DOA Press are highly appreciated. Finally, we would like to extend the most earnest gratitude to the organizing team of ASDA-2016 for their generous supports, hard work at the expense of their precious time.

Professor Gamini Pushpakumara Professor Buddhi Marambe Dr. Lalith Professor Pradeepa Silva Suriyagoda Dr. Ranjith Punyawardena Dr. Priyantha Weerasinghe Dr. Wijayasiri Weerakoon

Editors 8th September 2016

Annals of Sri Lanka Department of Agriculture 2016. 18: 1 - 5

GLYCEMIC INDEX OF IMPROVED RICE VARIEITES AS INFLUENCED BY DEGREE OF POLISHING AND PROXIMATE COMPOSITION INCLUDING AMYLOSE CONTENT

R. F. HAFEEL L.B.A.P. AMARARATHNA 2, T.H.T. CHAMINTHA 3, A.P. BENTOTA 4, D.S.DE Z. ABEYSIRIWARDANA 5, S.K.J. MUHANDIRAM 3 AND B. PERUMPULI 2

1Rice Research Station, Ambalantota, Sri Lanka 2 Faculty of Agriculture, University of Ruhuna, Mapalana, Sri Lanka, 3 District Hospital, Katuwana, Sri Lanka 4 Rice Research and Development Institute, Batalagoda, Ibbagamuwa, Sri Lanka 5 CIC Agri Businesses (Pvt), Ltd, Pelwehera, Dambulla, Sri Lanka

EXTENDED ABSTRACT

Type II diabetes is increasing at alarming rates in Sri Lanka and often not diagnosed until chronic conditions emerge. There were 1.16 million cases of diabetes in Sri Lanka in 2015 (IDF, 2015). Prevalence of diabetes mellitus is lower in people having diets with low glycemic index (GI) than in diets with high GI (McKeown et al., 2004). GI could be considered as a valid parameter in this attempt as it ranks food items depending on the blood glucose response following a meal. GI is defined as ‘the incremental area under the blood glucose response curve of a 50 g digestible carbohydrate portion of a test food expressed as a percent of the response to the same amount of carbohydrate from a standard food taken by the same person’. Foods are categorized into low (55 or less), medium (56-69) and high (70 or above) GI groups (Wolever, 1991).

Rice as Sri Lankans’ staple food is consumed two or three times daily or at least once in main meals by a Sri Lankan. Studying the GI of Sri Lanka’s rice will be of immense importance in such a situation. GI values in white rice have been obtained within a wide range of variability from 54 to121, in studies done around the world (Zarrati et al., 2008). Protein, fat, fibre and other nutrients in rice that vary among varieties may also influence the carbohydrate absorption which is related to health condition of the rice consumer (Wolever and Jenkins, 1986).Rice market in Sri Lanka comprises of red, white, long and short grains and raw and parboiled rice. Comparative studies among improved rice varieties for their GI and influence of proximate composition and bran removal or degree of polishing on GI of rice are limited. Thus, the objective of the present study was to compare improved rice varieties developed at the Rice Research Station (RRS), Ambalantota for their GI and to evaluate how degree of polishing and proximate composition including grain amylose content influence on GI.

2 HAFEEL et al.

A two factor factorial (RCBD) experiment with seven rice varieties(At 362, At 311, At 353, At 1078, At 309 At 405 and At 354) and two degrees of polishing (DP) (30% and 60%) was conducted at the RRS, Ambalantota during 2014/15 Maha season. Proximate composition including moisture (M), crude protein (CP), crude fat (CFa), crude fibre (CFb), and total ash content was determined by the official method of analysis (AOAC, 2000). Available carbohydrate content was calculated by subtracting the total nutrients (M, CP, CFa, CFb and ash) by 100. Amylose content was determined by the method of Cruz and Kush (2000).In vivo test for GI was conducted as described by Panlasigui et al. (1991), Yusof (2005) and Zarrati (2008).Eleven non-smoking and nondiabetic healthy volunteers comprising 8 women and 3 men (age/yrs 41.1 ± 11.2 and BMI 24.9 ± 1.05) took part in the study. The respective blood glucose concentrations were used to draw a response curve for the 2hr. period. The incremental area under the curve (IAUC) was calculated for each meal in every volunteer separately (Chlup et al., 2004). The GI for each tested food was calculated as the mean from the respective average GI’s of the 11 volunteers. Data were analyzed using ANOVA procedure. Whenever the interaction effects were significant they were further studied using response curves. Relationships among variety characteristics were studied using regression analysis under two degrees of polishing separately if the interaction effect of variety x degree of polishing for characteristics was found to be significant.

Two way interaction effect of Variety x DP was found to be significant with respect to GI. None of the tested varieties recorded high GI values. Except At 405 and At 354, all the other varieties recorded almost the same GI irrespective of DP. At 362, At311and At 1078 recorded low GI values and At 353 and At 309 recorded intermediate GI values irrespective of DP. At 405 and At 354 appeared highly sensitive to DP with respect to GI as they recorded low GI values at 30% DP and intermediate GI at 60%DP.Thus, these can be made low or intermediate GI depending on the DP.

The interaction effect of variety x DP was found to be significant for all the nutrient components of protein, fat, fibre, ash, carbohydrate and amylose indicating that different varieties responded differently to different degrees of polishing in all the nutrient components. In general, average effects of protein, fat, fibre and ash contents were significantly higher in rice varieties with 30% than 60% DP irrespective of the significant interaction effect of variety x DP. Carbohydrate contents were in converse. This was because unlike carbohydrate, other components such as protein,

GLYCEMIC INDEX OF IMPROVED RICE VARIEITES 3 fat, fibre and minerals are concentrated in the rice bran (Champagne et al., 2004). On the average At 354 recorded the highest (81.25%) and At 311 and At1078 recorded the lowest (77%) grain carbohydrate contents. The linear relationships between GI and grain carbohydrate content at both 30% and 60% DP were found to be not significant at 5% probability level, indicating that GI was not influenced by the grain carbohydrate content in improved rice irrespective of DP (Figure 1).

On the average At 354 recorded the lowest (4.8%) and At 311 and At 1078 recorded the highest (7.8%) grain protein contents. The relationship between GI and grain protein content was found to be not significant at 30% DP but was found to be significant at 60% DP at 5% probability level indicating that degree of polishing influenced the relationship between GI and grain protein content in improved rice(Figure 2). Higher the grain protein content, lower the GI in 60% polished rice and the rate of reduction in GI was 6.44 per 1% increase in grain protein content. This is in agreement with Chung et al. (2008) who reported comparatively lower GI values in samples with greater protein content. As a strategy, rice with more than 60% DP of varieties having grain protein content more than 5.5% can be considered as low GI (less than 55) rice.

A Y=1.12X -36.1 65 ns B Y=3.5X -228.2 R2 =0.33 £ 60 - H 60 R2 =0.368 5 55 - I 55 u " " u 50 S a 50 - H 45 45 3 40 £ 4 0 4 74 76 78 80 82 o 80 82 Carbohydrate content (°o) Carbohydrate content (°o) Figure 1. The linear relationships between GI and grain carbohydrate content at 30% (A) and 60% (B) degrees of polishing in improved rice [ns=not significant at p< 0.05].

The relationships between GI and grain fat (r 2 =0.239 at 30% and 0.45 at 60% DP), crude fibre (r 2 = 0.223 at 30% and 0.006 at 60% DP ), ash (r 2 = 0.002 at 30% and 0.068 at 60% DP ) and amylose contents (r 2= 0.037 at 30% and 0.055 at 60% DP) were found to be not significant at 5% probability level at both 30% and 60% DP indicating that GI was not influenced by any of those nutrients in improved rice irrespective of DP. Yusof et al. (2005) reported that though many factors contribute to influence GI, dietary fibre has no relationship to GI and Panlasigui et al. (1991) reported that amylose content in rice is not a good predictor for starch digestibility and glycemic response. Van et al ., (2015) also found that there was no correlation between amylose content and GI or the resistant starch content.

Protein contentY= - 6.437X (%) + 90.4 Figure 2. The linear relationships between GI and grain protein content at 30% (A) and 60% (B) degrees of polishing in improved rice. (*=significant, ns=not significant at p< 0.05). 4 HAFEEL et al.

Pro tein content (%) GI of improved ‘At’ varieties ranged from low to medium. None of them recorded high GI. Influence of degree of polishing on GI was variety dependent. Grain carbohydrate, amylose, fat, crude fibre and ash contents had no influence on GI in improved ‘At’ rice. However, at 60% degree of polishing GI reduced from intermediate to low as the grain protein content increased but not at 30% degree of polishing.

REFERENCES

AOAC. 2000. Official methods of analysis. Association of Official Analytical Chemist, Washington DC. Champagne, E.T., D.F. Wood, B.O. Juliano and D.B. Bachtel. 2004. The rice grain and its gross composition. Ed. E. T. Champagne. Rice Chemistry and Technology. 3rd ed. Pp. 77-107. Chlup, R., Bartek, J., Rznickova, M., Zapletalova, J., Doubravova, B. Chlupova, L. Seckar, P. Dvorackova, S. and Simanek, V. 2004. Determination of the glycaemic index of selected foods (white bread and cereal bars) in healthy persons. Biomed. Papers 148(1), 17-25. Chung H.J., Q. Liu, R. Hoover, T.D.Warkentin, and B. Vandenberg. 2008. In vitro starch digestibility, expected glycemic index, and thermal and pasting properties of flours from pea, lentil and chickpea cultivars. Food Chemistry 111:316-21. Cruz, N. D. and G. S. Kush. (2000). Rice grain quality evaluation procedures. pp. 15-28. Chapter 3. In: Singh, R.K., Singh, U.S. and Kush, G.S. (Eds). Aromatic rices. International Rice Research Institute, Philippines. Oxford Publishing Co. Pvt Ltd. New Delhi. IDF (International Diabetes Federation). 2015. Diabetes in Sri Lanka. Available at http://www.idf.org /global-diabetes-scorecard) [Accessed on 01/02/2016]. McKeown N.M., J.B. Meige, S. Liu, E. Saltzman, P.W. Wilson, P.F. Jacques. 2004. Carbohydrate nutrition, insulin resistance and the prevalence of the metabolic syndrome in the Framingham Offspring Cohort. Diabetes Care. 27: 538-46

GLYCEMIC INDEX OF IMPROVED RICE VARIEITES 5

Panlasigui, L.N., L.U. Thompson, B.O. Juliano, C.M. Perez, S.H. Yiu and G.R. Greenberg. 1991. Rice varieties with similar amylose content differ in starch digestibility and glycemic response in humans. The American Journal of Clinical nutrition.54: 871-7 Van H.P, H.T. Chau, and N.T. Phi. 2015. In vitro digestibility and in vivo glucose response of native and physically modified rice starches varying amylose contents. Food Chemistry 191:74-80. Wolever, T.M.S., D.J.A. Jenkins, A.L. Jenkins, R.G. Josse. 1991. The glycemic index: methodology and clinical implications. American Journal Clinical Nutrition 54: 846-54 Wolever, T. M. S. and D.J.A. Jenkins. 1986. The use of glyceamic index in predicting the blood glucose response to mixed meals. The American Journal of clinical nutrition.43: 167-172 Yusof, B.N.M., R. Abd Talib and N.A. Karim. 2005. Glycaemic index of eight types of commercial rice. Mal J Nutr 11: 151-163 Zarrati, M., M. Pirali, P.Mirmiran, N.Noori, K. Nakhoda, H. Najafi, and H. Hoseini. 2008. Glycemic index of various brands of rice in healthy individuals. International Journal of Endocrinology and Metabolism, 4: 200-204

Annals of Sri Lanka Department of Agriculture 2016. 18: 6 - 8

LONG TERM APPLICATION OF ORGANIC MANURE AND CHEMICAL FERTILIZERS ON RICE RODUCTIVITY AND FERTILITY IN PADDY GROWING SOILS IN KURUNEGALA DISTRICT

D.N. SIRISENA, W.M.N. WANNINAYAKE AND A.G.S.D. SILVA

Rice Research and Development Institute, Batalagoda, Ibbagamuwa

EXTENDED ABSTRACT To improve overall soil fertility and crop yield, applications organic manure and chemical fertilizer have been recommended for many rice grown soils in Sri Lanka (Bandara et al, 2005). Though this strategy could influence for soil productivity in long run, research data are demand to prove the influence of long term application of organic manure and chemical fertilizer on grain yield and soil fertility. Therefore, experiment was conducted at the RRDI, Batalagoda to study the influence of long term application of organic manure and chemical fertilizers on rice productivity and soil fertility in imperfectly drained red yellow podzolic soils (haploudults) in Kurunegala district.

Four plots were maintained in this experiement with four fertilizer treatments, namely (i) no organic manure or chemical fertilizer (control), (ii) only organic manure OM, (iii) only chemical fertilizer CF and (iv) organic manure plus chemical fertilizer OM + CF. Added organic manure rates were 5 t/ha straw, 1 t/ha green manure and 4 t/ha cattle manure. Chemical fertilizers were Urea, triple super phosphate (TSP) and muriate of potash (MOP) added as 105 N kg/ha, 35 kg P 2O5/ha and 30 kg K 2O/ha respectively. Experiemnt was conducted for 22 seasons (11 years) and Bg 358 was transplanted in all easons. Yield data were recorded and soil samples were collected from each plot at the beginning and at end of 11 years and analyzed for pH, electrical conductivity (EC), organic matter (OM), total N, available P, and exchangeable K.

Highest grain yields were always observed in plots treated with organic manure and chemical fertilizer and lowest yields were observed in control plots (Figure 1). Average yields of chemical fertilizer and organic manure treated plots are 5.54 t/ha in Yala and 5.46 in Maha seasons while respective values for control plots are 3.01 t/ha in Yala and 2.71 t/ha in Maha seasons (Table 1). Yields of the all treatment has declined with time but that of control plots has declined significantly (P>0.05) in yala season. Such a significant decline in grain with time was not observed in other treatments.

LONG TER APPLICATION OF ORGANIC & CHE MICAL FERTILIZERS ON RICE YIELD 7

Control OM only -CF only OM + CF

Figure 1. Grain yield of treatments for 11 consecutive years.

Table 1 Average grain yield of four treatments in yala and maha seasons of 11 years. Treatments Yala yield (t/ha) Maha yield (t/ha) Control 3.01 ± 0.56 2.71 ± 0.56 OM only 4.04 ± 0.73 3.50 ± 0.53 NPK only 5.12 ± 0.71 5.00 ± 0.28 OM + NPK 5.54± 0.86 5.46 ± 0.37

The highest level of organic matter as well as total nitrogen was recorded in treatments with organic manure. After 11 years of cultivation without application of organic manure or chemical fertilizer, total nitrogen content in paddy soils has reached to the lowest level of 0.03. It was lower than the initial value in control plots, but increased above the initial level when organic manure was added (Table 3). In comparison to control plot, available P content was at higher level when P was added

through fertilizers or manures. Despite annual P and K additions at 35 kg P 2O5 and 30

kg K 2O /ha through chemical fertilizers and application of organic manures at 10t/ha, available P and exchangeable K contents did not reach above the critical level. This may be due to higher fixation of P by paddy soils and higher removal of K by rice crops (Bandara, 2006, Dhamayanthi, 2001).

It can be concluded from this study that despite annual additions of nutrients at recommended rates through fertilizers as well as organic manures at 10t/ha, available nutrient especially P and K contents have not increased over the initial level. More organic matter content and total N were recorded in organic manure treated plots than that of non-treated plots. Yield declining was observed in all 4 treatments with time but highest declining was observed in control plots in yala seasons. Combined application of organic manure and chemical fertilizer is necessary not only to obtain higher grain yield in immediate season and in long run but also to maintain soil fertility in long run.

8 SIRISENA et al. REFERENCES

Bandara,W.M.J, D.Kumaragamage, D.B.Wickramasinghe and S.B.A.Weerawarna. 2005. Site specific nutrient management strategy to increase rice yields in Low Country Intermediate Zone. J. Soil Sci. Soc, of Sri Lanka 17: 32-43 Bandara, W.M.J. 2006. A Site -specific fertilizer recommendation for rice (Oryza sativa L.) using a systemic approach to soil fertility evaluation. Thesis submitted in partial fulfillment of the requirement of the degree of Doctor of Phylosophy in Agriculture. University of Peradeniya, Sri Lanka Damayathi, M.R.C. 2001. Phosphorous retention ability of five Sri Lankan soils under flodded and dry conditions. Report submitted in partial fulfillment of the requirement of the degree of Bachelor of Science in Agriculture, University of Peradeniya Sri Lanka. Wickramasinghe, W.M.A.D.B., J.D.H. Wijewardena 2000. Soil and nutrient management for increasing soil fertility towards increased rice productivity in Sri Lanka. Annals of the Sri Lanka Department of Agriculture, Peradeniya. 2: 465-482.

Annals of Sri Lanka Department of Agriculture 2016. 18: 9 - 12

DETERMINATION OF EFFECT OF COOKING ON TOTAL POLYPHENOL AND ASCORBIC ACID CONTENT AND ANTIOXIDANT ACTIVITY OF FIVE COMMON GREEN LEAFY VEGETABLES AND CURRY LEAVES

S.M.A.C.U. SENARATHNE, D.K. WIJERATHNE, K.W.P.D. KARANDAWALA

AND K.H. SARANADA

Food Research Unit, Gannoruwa, Peradeniya, Sri Lanka

EXTENDED ABSTRACT Vegetables cannot be compared with their caloric contribution in the context of human nutrition but ensure a good health mainly due to the presence of vitamins and provitamins such as ascorbic acid, tocopherols and carotenoids and they also rich in a wide array of phenolic substances having strong antioxidant properties (Loliger, 1991). The Principal function of antioxidants is in delaying the oxidation of other molecules by inhibiting the initiation or propagation of oxidizing chain reactions by free radicals and they may reduce oxidative damage to the human body (Namiki, 1990). The occurrence of such oxidative damage may be a significant causative factor in the development of many chronic diseases such as cancer and cardiovascular diseases (Lindley, 1998). As an antioxidant, the primary role of vitamin C (Ascorbic acid) is to neutralize free radicals. U.S. Food and Drug Administration in 2015 has adopted a recommended dietary allowance (RDA) of 90 mg/day for men and 75 mg/day for women.

Cooking and processing may affect the antioxidant content in vegetables, especially components such as tocopherol, carotenoids, ascorbic acid and polyphenols. Antioxidant activity of Kale, Spinach and swamp cabbage was observed to decrease after thermal treatment (Ismail et al., 2013). Common meal of Sri Lankan diet consists of rice and curry together with leafy vegetables. Commonly consumed leafy vegetables are; Ipomoea aquaticas (Kankun), Centella asiatica (Gotukola), Trianthema monogyna (Sarana), Alternanthera sessilis (Mukunuwenna), and Murraya koenigii (Karapincha) and Lactuca sativa (Salad leaves/ Lettuce) are taken both fresh form (Sambol) and cooked form (Mallung). Thus, this study was carried out to determine the TPC, AAC and AA of fresh and cooked green leafy vegetables.

Five commonly consumed fresh Green Leafy Vegetables (GLVs) namely, Kankun, Gotukola, Sarana, Mukunuwenna, Salad leaves/Lettuce and Karapincha were washed, air dried and two treatments such as fresh form and cooked form (heat treatment; 2-3 min, received temperature 78±2 0C) were given. The amount of total polyphenols was determined according to the method of Abdelrahman et al. (2014). The 2, 6- Dichlorophenol Indophenol visual titration method (Rangana, 1977) was used to determine the ascorbic acid content. Radical scavenging activity of leafy vegetables was measured by slightly modified method of Abdelrahman et al. (2014). Chemically analyzed data were subjected to one-way Analysis of Variance (ANOVA) and the significance of differences between means were assessed using Least Significant

10 SENARATHNE et al.

Difference (LSD) performed by SAS Statistical programme (Version 9.1).

Salad leaves contained the highest TPC content followed by Gotukola with a value of 135.8mg/100g and 125.3mg/100g, respectively (Table 1) Among cooked samples of Karapincha showed the highest TPC (126.2 mg/100g) followed by Sarana (122.3mg/100g), Gotukola (117.6 mg/100g), Mukunuwenna (97.1 mg/100g) and Kankun (91.4 mg/100g) whereas cooking reduced the TPC of Sarana by (6.1%) and Karapicha (54.3%). Adefegha and Oboh, (2011) found that cooking increases TPC levels in some vegetables due to the disruption of cell walls, which liberate soluble phenolic compounds from insoluble ester bonds.

Table 1. Total polyphenol content of selected green leafy vegetables and Karapincha when fresh form, cooked form and percentage reduction when cooked. Leafy vegetable Fresh form Cooked form TPC reduction (mg/100g) (mg/100g) (%) Kankun 113.65 a±1.45 091.37 a±1.20 19.60 Gotukola 125.33 a±1.56 117.55 a±2.59 06.18 Sarana 116.46 a±2.52 122.25 a±2.29 -04.90 Mukunuwenna 112.87 a±1.76 097.01 a±1.59 14.05 b a Karapincha Salad 081.79 ±0.86 126.23 ±2.97 -54.33 a leaves 135.83 ±1.91 Values are Means ± Standard error of 5 replicates. Treatment means having common letter(s) are not significantly different by LSD 5% in each column.

The highest amount of AAC was found in Sarana at 22.8 mg/100g and the lowest amount was observed in Salad leaves at 3.2 mg/100g (Table 2). Cooking decreases the AAC of all the GLVs and Karapincha. The highest reduction of AAC was observed in Mukunuwenna by 45.9% followed Sarana 31.9% (Table 2). Previous studies have shown that cooking reduces AAC in fruits and vegetables (Somsub, 2008) as AAC is destroyed during cooking because it is unstable at high temperature. The higher IC 50 values have the lower anti-oxidant capacity. Therefore, observed IC 50 values suggest that fresh salad leaves showed the highest anti-oxidant capacity followed by Sarana and Mukunuwenna. With cooking, Kankun and Gotukola showed 19.7% and 25.8% reduction of IC 50 value, respectively and 40% of Karapincha. A remarkable increase in AA was observed in Sarana (235.9%), Salad leaves (226.3%) and Mukunuwenna (76.4%) among other GLVs. The lowest anti-oxidant capacity was showed in Gotukola among the GLVs tested. Cooking imposed in this study revealed that Karapincha had the highest anti-oxidant

EFFECT OF COOKING ON CHEMICAL PROPERTIES SELECTED GREEN LEAFY VEGETABLES AND CURRY LEAVES 11 capacity followed by Gotukola. However, AA of Gotukola and Karapincha are reduced by significantly higher amounts with cooking (Table 3).

Table 2. Ascorbic acid/ mg/100g of selected green leafy vegetables and karapincha when fresh form, cooked form and % reduction when cooked. Leafy vegetable Fresh form Cooked form AA reduction (mg/100g) (mg/100g) (%) Kankun 12.49 bc ±0.47 07.93 bc ±0.99 36.5 Gotukola 13.86 c±0.99 11.00 ab ±0.62 14.3 Sarana 22.77 a±0.84 15.50 a±0.55 31.9 Mukunuwenna 19.70 ab ±0.44 10.66 ab ±0.64 45.9 Karapincha 17.20 abc ±0.56 12.33 ab ±0.96 28.3 d c Salad leaves 03.20 ±0.37 03.13 ±0.37 02.2 Values are Means ± Standard error of 5 replicates. Treatment means having common letter(s) are not significantly different by LSD 5% in each column.

Table 3. Antioxidant activity (IC 50 value) of selected GLVs when fresh form, cooked form and % reduction when cooked. Leafy vegetable Fresh form (ppm) Cooked form (ppm) AA reduction (%)

Kankun 32.00 a±0.25 25.67 a±0.49 019.8 Gotukola 33.70 a±0.23 25.00 a±0.28 025.8 Sarana 09.03 ab ±0.95 30.33 a±0.43 -235.9 Mukunuwenna 14.17 ab ±0.38 25.00 a±0.27 -076.4 Karapincha 15.90 ab ±0.34 09.50 a±0.31 040.3 Salad leaves 05.67 b±0.11 18.50 a±0.15 -226.3 Values are Means ± Standard error of 5 replicates. Treatment means having common letter(s) are not significantly different by LSD 5% in each column

Cooking temperature is a factor which dramatically affects the nutrient retention. The extraction solvent and measured methodology may affect the results. It has been found that less polar solvents provided slightly more active extracts than mixtures with ethanol or methanol, or methanol alone for Tamarind seed coats (Cao et al. 1996). This factor may also have affected the results in the different findings of this study. Thus, there is a relationship of AA with AAC and total TPC, but this has to be further studied in respective of GLVs and Karapincha with more heat treatments involved.

Both GLVs and Karapincha used in this study had high total polyphenol content and cooking reduced it slightly only. GLVs are generally good sources of vitamin C; however, cooking leads to loss substantially. High AA in Salad leaves and Sarana reduced significantly upon cooking. Fresh Karapincha leaves contain a fairly high amount of AA which increases substantially upon cooking. It can be concluded that fresh

12 SENARATHNE et al. form (‘Sambol’) is the best way to consume green leafy vegetables, but cooked form (‘Mallung’) also do not change the TPC of studied GLVs and Karapincha and AA of Kankun, Gotukola and Karapincha.

REFERENCES

Abdelrahmann, M., S. Hirata, Itchiu Ito, N. Yamauchi and M. Shigyo, 2014. Compartmentalization and localization of bioactive metabolites in different organs of Allium roylei, Bioscioence, Biotechnology and Biochemistry, 78, 1112-1122.

Adefegha, S.A. and G. Oboh. 2011. Cooking enhances the anti-oxidant properties of some tropical green leafy vegetables. African Journal of Biotechnolohgy, 10:632-639.

Cao, G., E. Sofic and R.L. Prior, 1996. Antioxidant capacity of tea and common vegetables, Journal Agriculture and Food Chemistry, 44, 3426-3431.

Ismail, A., M.M. Zamaliah and C.W. Fong, 2013.Total antioxidant activity and polyphenol content in selected vegetables, Department of Nutrition Health, pp. 355-360.

Lindley, M.G., 1998. The Impact of food processing on antioxidants in vegetable oils, fruits and vegetables, Trend in Food Science and Technology, 9, 336-340.

Loliger, J., O.I. Aruoma and B. Haliwel (Eds.) 1991. Free radicals and food additives, Taylor Francis, London. pp. 121-150.

Namiki, M., 1990. CRC Critical review food science and nutrition, 29, 273-300.

Rangana, S., 1977. Manual of analysis of fruits and vegetable products, Central food technological Institute, Mysore, Chapter 1 pp. 1-3.

Somsub, W., R. Kongkachuichai, P. Sungpuag and R. Charoensiri. 2008. Effects of three conventional cooking methods on vitamin C, tannin, myo-inositol phosphates contents in selected Thai vegetables. Journal of Food Composition Analysis, 21:187-197.

Annals of Sri Lanka Department of Agriculture 2016. 18: 13 - 15

TRANSMISSION AND HOST RANGE STUDIES OF SRI LANKAN ISOLATE OF CHILLI VEINAL MOTTLE VIRUS IN CHILLI

C. RANASINGHE 1, B. DHARMARATHNA 2, R.T. EKANAYAKE 1 AND S. GEETHIKA 1

1Plant Virus Indexing Centre, Gabadawattha, Homagama, Sri Lanka 2 Department of Export Agriculture, Faculty of Agricultural Science, University of Sabaragamuwa, Belihul Oya, Sri Lanka

EXTENDED ABSTRACT

Chilli ( Capsicum annum L.) is one of the major cash crops grown in Sri Lanka, belonging to the family Solanaceae. Viruses are the most devastating agents of Chilli, causing serious losses by reducing both fruit quality and quantity (Chew and Ong, 1990). So far 65 viruses have been reported infecting Chilli crop throughout the world (Anon., 2001). It has been reported that Chilli veinal mottle virus (ChiVMV) is one of the most problematic virus of Chilli pepper (Anon, 2001). Symptoms of ChiVMV range from mild to severe mottle, with variation in leaf malformation, shoestring and leaf curling (Hidayat et al., 2012). This virus is transmitted by aphids, mechanical inoculation and grafting (Hussain et al., 2008). However, it has not transmitted through seeds (Green, 1999).

It would be possible to eradicate this disease through exact identification of host range and transmission methods of this virus. There are no records on host range and transmission studies on the Sri Lankan isolate of ChiVMV. Therefore, this study was directed to investigate the transmission and host range of Sri Lankan isolate of ChiVMV in order to put an effort to manage this virus by exploring its biological properties. It may help to suggest crop recommendations for mix cropping and crop rotation.

This experiment was conducted at the Plant Virus Indexing Center, Homagama, from 2015 April to July. Suspected host plants for ChiVMV were listed out (thirty two plant species consisting of eleven crop species and twenty one weed species) based on literature survey and through the observation of Chilli fields in Wet, Dry and Intermediate zones. Healthy plants of above selected species were inoculated with ChiVMV by mechanical sap transmission, aphid ( Aphis gosypii ) transmission and graft transmission and kept inside insect proof net cages. Symptom development was observed daily and symptomatic plants were subjected to DAS-ELISA test for the confirmation of ChiVMV infection. Mechanical, vector and graft transmission methods were compared with uninoculated plants to determine the best transmission method. Absorbance values

14 RANASINGHE et al. which resulted from the DAS-ELISA test was analyzed by one-way ANOVA procedure.

Capsicum annum (Solanaceae) (Chilli) was infected in ChiVMV by all three inoculation methods with showing characteristic symptoms and giving positive results to the ELISA test. Physalis angulate (Solanaceae) (cape gooseberry) plants showed leaf curling and mottling symptom in both mechanical and graft transmission methods and also gave positive results to the ELISA test. Phyllanthus amaranthus (Euphorbiacea) (sudu pitawakka) plants showed curling in vector transmission and gave positive reaction to the ELISA. But grafted plants gave negative reaction to the ELISA, even though showed vein banding symptoms. Rauvolfia densifolia (Apotynaceae) (wild ekaweriya) showed curling and chlorotic patches by vector transmission and positive to the ELISA. Even though showed curling symptoms in grafted plants, it was negative to the ELISA. Solanum violaceum (Solanaceae) (thibbatu) showed severe curling in graft transmission and gave positive reaction to the ELISA. But vector transmitted plants showed negative reaction to the ELISA even though showed curling and mottling symptoms.

In graft transmission, mild curling in S. melongena (Solanaceae) (brinjal), severe yellowing in Crotalaria incana (Leguminoceae) (andanahiriya) and yellowing and curling in Cassia occidentalis (Fabaceae) (pani thora) were observed. Further, those plants gave boarder line reaction in ELISA test.

Chenopodium amaranticolor (Chenopodeace) (goose foot) showed chlorosis in mechanical inoculation but not give positive to the ELISA even though it act as an indicator plant for ChiVMV. Conyza anadensis (Asteraceae) (sudana) showed severe curling symptoms in mechanical inoculation but not proved the infection by ELISA test.

Vein banding and mild chlorosis in Vigna ungiculate (Fabaceae) (long bean), mild mottling in Psophocarpus tetragonolobus (Fabaceae) (dambala) and curling in Cleome viscose (Capparidaceae) (wal aba) showed in vector transmission, but infection not proved by ELISA. Leaf curling in Eupotorium odoratum (Asteraceae) (podisinnomaran) was observed in both vector and graft transmitted plants but not give positive reaction to the ELISA. Even though, S. americanum (Solanaceae) (kalukammeriya) showed curling and mottling by vector transmission and severe curling and mild mottling by graft transmission, gave negative reaction to the ELISA. Grafted S. mauritianum (Solanaceae) (wild tobacco) plants were negative to the ELISA, even though showed mild curling.

HOST RANGE STUDIES OF SRI LANKAN CHILLI VEINAL MOTTLE VIRUS 15

According to this study, plant species which belongs to Solanaceae, Apotynaceae and Euphorbiaceae were infected by ChiVMV. Lee (1992) reported that, weed species infected by ChiVMV included members of families Solanaceae, Amaranthaceae, Boraginaceae, and Compositae. But Ong et al. (1979), Prakash et al. (2002) and Hussain et al. (2008) reported that the host range of ChiVMV is restricted to Solanaceae. Graft transmission is the best method for the transmission of ChiVMV.

This study revealed that, Sri Lankan isolate of ChiVMV is transmitted mechanically via sap, through aphid vector (A. gosypii) and grafting to their hosts. P. angulata, S. violaceum, R. densifolia and P. amaranthus were confirmed as alternative hosts for Sri Lankan isolates of ChiVMV with characteristic symptoms and giving positive reaction to the ELISA test. The information can be used in the management of ChiVMV in Chilli. This is the first report of plants of Apotynaceae and Euphorbiaceae families acting as hosts and also the first report of S. violaceum and P. amaranthus act as a host of ChiVMV.

REFERENCES

Anonymous. 2001. Proceedings of the South Asia Vegetable Research Network (SAVERNET-II) Final Workshop 3-8 June 2001, Bangkok, Thailand. Asian Vegetable Research and Development Centre, Shanhua, Tainan, Taiwan. Chew, B.H. and C.A. Ong. 1990. Genetics and breeding for Chilli veinal mottle virus and Chilli veinal mottle virus resistance in hot pepper. Trop.Gen., 20-23. Fujisawa I., S.H. Anang, Y. Shen and A. Zhou. 1986. Virus diseases occurring on some vegetable crops in West Malaysia. JARQ. 20(1): 78-84. Green, S.K. 1999. Characterization of chilli veinal mottle virus as a potyvirus distinct from pepper veinal mottle virus. Petria. 9(3): 332. Hidayat, S. H., E. Opriana, I. Manzila and S. Sujiprihati. 2012. Occurrence of chili veinal mottle virus (chivmv) in indonesia and response of chili germplasms to CHIVMV infection. Journal of ISSAAS.18 (2):55-61. Hussain, S., T. Yasmin, M. Fahim, S. Hameed and M.I. Haqie. 2008. Transmission and host range study of Pakistan isolate of chilli veinal mottle virus . Pakistan Journal of Botany, 40(6): 2669-2681. Lee, K.M. 1992. Transmission and pattern of spread of Chilli veinal mottle virus by Aphis Gossypii Glover (Homoptera: Aphidiceae) Faculty of Science, University of Pertanian, Malaysia. Ong, C.A., G. Varghese and W.P.Ting. 1979. Aetiological investigation on a veinal mottle virus of chilli (Capsicum annuum L.) newly recorded from peninsular Malaysia. MARDI, Research Bulletin, 7: 278-288. Prakash, S., S.J. Singh, R.K. Singh and P.P. Upadhyaya. 2002. Distribution, incidence and detection of a Potyvirus on chilli from eastern Uttar Pradesh. Indian Phytopathology 55(3): 294-298.

Annals of Sri Lanka Department of Agriculture 2016. 18: 16 - 15

COMBINING ABILITY, HERITABILITY AND GENE ACTION ANALYSIS OF YIELD AND SOME YIELD CONTRIBUTING CHARACTERS IN CHILLI (CAPSICUM ANNUUM L.) INBRED LINES

H.M.S.N. HERATH, H.M.S. BANDARA, W.G. WIJEPALA AND H.M. KARUNARATHNE

Field Crops Research and Development Institute Mahailuppallama, Sri Lanka

EXTENDED ABSTRACT

Chilli is cultivated in Sri Lanka mainly for green chilli and dry chilli. During 2014, 13,978 ha of chilli were cultivated with the production of 71,767 t. In the same year, 46,422 t of dry chilli worth Rs 7,578 million were imported (DOA, 2014). In the backdrop of increasing chilli production in the country, development of superior chilli hybrids and open pollinated chilli varieties, combining desirable agronomic traits is a requisite to improve the chilli production in Sri Lanka. Diallel analysis is one of the methods to determine the appropriate parents depending on combining ability and gene action. Based on the information of combining ability and gene action, selected lines combined either to exploit hybrid vigour by accumulating non-additive genetic effect or to evolve open pollinated varieties by accumulating additive genetic effect (Saleem et al. , 2013). Estimation of heritability is a pre requisite for the amelioration of quantitative traits and choosing the selection procedure that will maximize genetic gain. The aim of this study was to estimate the general combining ability, specific combining ability, additive and non-additive genetic effect and heritability effect using yield and seven yield related agronomic characters of chilli. Identification of superior genetic combinations to develop hybrids and open pollinated varieties and the determination of genetic components involved in the expression of the studied traits were other objectives.

This experiment was conducted during Maha 2014/15 and Yala 2015 at the Field Crop Research and Development Institute (FCRDI), Mahailuppallama. Eight inbred lines namely, MICH PL 22, MICH PL 23, MICH PL 19, MICH PL 24, MICH PL 25, MICH PL 26,MICH PL 11, MICH PL 14 were selected for this study. Thirty-day-old seedlings of these parental lines were planted in clay pots during Maha 2014/15. Crosses were made at flowering following diallel design without reciprocals by hand emasculation and pollination. Ripened pods were harvested and F1seeds were extracted separately. F1 seeds of crosses and seeds of their parents were sown in nursery trays and they were transplanted after 30 days in the field during Yala 2015. Each plot (6.0 m x 1.8 m) consisted of 50 plants at the spacing of 60 cm x 60 cm and 1 plant per hill. Randomized complete block design with two replicates was adopted. Harvesting was practiced in 10 days interval starting form 70 days after field planting. Number of

COMBINING ABILITY, HERITABILITY AND GENE ACTION ON YIELD IN CHILLI 17 pods and fresh green chilli yield of F1 hybrids and parents were recorded. Pod diameter and pericarp thickness was recorded on 10 randomly selected pods of 10 plants from each replicate. Pod length, was recorded on randomly selected 10 pods from 10 plants from each replicate. Height and canopy width was measured in 10 randomly selected plants from each hybrid and parent. Number of days was taken to commence 50% flowering was also recorded. Estimation of combining ability variances and effect for yield and yield related agronomic characters was done using the method 2 and model II of Griffing according to Chaudhary and Singh (1985). Heritability for yield and yield related agronomic character was calculated translating estimated variance component in to different component of phenotypic variances as suggested by Hasanuzzaman et al. (2012).

Analysis of variance for combining ability showed that the GCA variances were significant for all the tested characters. Significant SCA mean squares were observed for all the characters other than pod length, pericarp thickness and canopy width. The magnitude of estimated additive genetic variance was higher than the non-additive genetic variance for all the tested agronomic characters. According to Doshi and Shukla (2000) additive gene action revealed predominance for number of pods/plant, pod length and pod weight. Progeny selection can be practiced to accumulate desirable genes for the tested characters since the higher magnitude of additive genetic variance. According to the GCA of eight parental lines, none of the parents was a good general combiner for all tested characters. Parent lines, MICH PL 14 exhibited significant positive GCA for all characters except days to 50% flowering. The parental lines having high GCA showed high mean performance. It indicates that parents can be identified based on GCA values, mean performance or by combination of both. Significant positive or negative SCA among 28 hybrids indicated the possibility of exploiting hybrid vigour for all the tested characters. Most of the crosses having significant SCA exhibited high mean values. However, no single cross contributed as good specific combiner for all tested characters. The cross, MICH PL 19 x MICH PL 11 exhibited significant SCA and high mean performance for all considered characters other than days to 50% flowering and number of pods/plant. High positive values of SCA for yield was obtained in crosses, MICH PL19 x MICH PL 11, MICH PL 25 x MICH PL 14, MICH PL 26 x MICH PL 14, MICH PL 11 x MICH PL 14. The crosses of MICH PL 22 x MICH PL 19, MICH PL 22 x MICH PL 25, MICH PL 23 x MICH PL 19 exhibited high positive SCA for number of pods/plant. Specific crosses for days to 50% flowering with significant negative values were MICH PL 22 x MICH PL 26, MICH PL 19 x MICH PL 14, MICH PL 25 x MICH PL 11. These crosses are good combiners for early bearing. Both additive and non-additive genetic variances were important in the inheritance of tested agronomic characters. Since the magnitude of additive genetic variance was high, open pollinated chilli varieties can be developed by fixing desirable traits through progeny selection. High broad sense heritability for all the characters

18 HERATH et al. showed the possibility of fixing these traits through selection. Inbred lines, MICH PL 22/2014, MICH PL 14/2014, MICH PL 25/2014 with significant GCA for many characters can be used in future for the development of chilli hybrids. The F1 crosses, MICH PL 11/2014 x MICH PL 14/2014, MICHPL 25 x MICH PL 14/2014, MICHPL 26/2014 x MICH PL 14/2014 with high mean value and significant SCA values for yield indicate their possibility of selecting as successful hybrids for further testing.

REFERENCES

Chaudhary, B.D. and R.K. Singh. 1985. Biometrical Methods in Quantitative Genetic Analysis. Kalyani Publishers. Pp 140-145. DOA. 2014. Agstat. Socio Economic and Planing Centre. Department of Agriculture. Peradeniya. 11:16. Doshi. K.M., and P.T, Shukla. 2000. Combining ability analysis for fresh fruit yield and its component over environments in chilli (Capsicum annuum). Capsicum Eggplant Newsletter. 19: 82- 85. Hasanuzzaman, M., M.A. Hakim, J. Fersdous, M.M. Islam, L. Rahman. 2012.Combining ability and heritability analysis for yield and yield contributing characters in chilli (Capsicum annuum) landraces. Plant Omics Journal. 5:337-344. Saleem., M.Y., M. Asghar, Q.Iqubal, A.U. Rahman, M. Akram. 2013. Diallel analysis of yield and some yield component in tomato (Solanum lycopersicum L). Pakistan Journal of Botany 45:1247-1250.

Annals of Sri Lanka Department of Agriculture 2016. 18: 19 - 22 TOXIC TRACE ELEMENTS IN VEGETABLES COLLECTED FROM MARKETS IN KANDY DISTRICT

N.R.N. SILVA 1, P. WEERASINGHE 1 AND H. D. K. RATHNAPRIYA 2 1 Horticultural Crops Research & Development Institute, Peradeniya, Sri Lanka 2 Bio-Food (Pvt.) Ltd., Panampitiya, Dambulla, Sri Lanka EXTENDED ABSTRACT

Toxic trace elements are environmental pollutants, particularly in areas with high anthropogenic pressure (Ghosh et al, 2013). Contamination of toxic trace elements via agricultural inputs such as fertilizer, manure and pesticides could be a major problem as most of such elements are persistent in environment due to their immobile nature (Mc Bride, 2003). Such elements hence could contaminate the agricultural produce under heavy input use. The transfer of trace elements from agricultural inputs in to soil and subsequently to plants pose a potential health risks because they can enter the food chain and contaminate the environment (Ghaediet al., 2008). Vegetable growing farmers in intensive areas grow 2-3 crops per year in the same land and apply high doses of fertilizers and other agrochemicals (Wijewardena and Yapa, 1999). Chemical fertilizers manure and pesticides contain toxic trace elements either as an active ingredient or as impurities (Premarathna et al., 2011). Objectives of this study were to assess toxic trace metal contents in vegetables obtained from the Kandy market and to estimate the dietary intake of different toxic trace element via vegetable consumption.

Nearly 250 g of fresh vegetable of carrot (Daucus carota), beet (Beta vulgaris), leek (Allium ampeloprasum), potato(Solanum tuberosum), beans (Phaseolus vulgaris), cabbage (Brassica oleracea), brinjal (Solanum melongena), bittergourd (Momordica charantia ) and capsicum ( Capsicum annum ) were collected during the period of August to September, 2013. Total number of 182 vegetable samples from public fairs, public markets, super markets and retail outlets from 10 locations were collected covering Kandy district. Samples were brought to the laboratory and sample preparation was done immediately without being stored in a refrigerator. Samples were washed with tap water and rinsed with distilled water and root and tuber vegetables were peeled off and washed again with tap water followed by distilled water. Fresh weight of whole sample was recorded after water on the surfaces evaporated and oven dried at 60 0C until a constant weight is reached. The oven dried whole sample was ground using a metal free stainless steel grinder and passed through a 0.5 mm sieve. Dried and ground vegetable samples were homogenated and 0.5 g of sample was digested with 8.0 ml of Conc. HNO 3 (69%, Analytical Grade) and H 2O2(30%) in a microwave digester (Model No. Milestone Start D HPR - 100/105). Metal analysis was performed as described by USEPA 3051 (1994).A blank digestion was also performed using the digestion mixture without a sample. Toxic trace elements of Cu, Zn, Pb, Cr and Cd, were determined by Atomic Absorption Spectrometer (Model Varian AA140/240/280) while As was measured using Hydride vapour Generator (vGA)

20 SILVA et al. assemblage of the AAS. As total fresh weight of the sample was predetermined, this content was taken as the content in fresh weight of the whole sample. Standard reference material of tomato leaves (1,573a) issued by National Institute of Standard and Technology, USA was used to validate the analytical results.

There was a significant correlation (r 2=0.998) between the certified and measured values for standard reference materials. Recoveries of all metals studied were greater than 85% except for Cr. Percentage recovery of the Cr was 73%. All the vegetables used in the experiment contained more than 83% moisture on fresh weight basis. Toxic trace element contents in all vegetable samples were in the range of 0.4 -5.7 mg/kg for Cu, 0.45-13.5 mg/kg for Zn, 0.01-1.0 mg/kg for Pb, 0.0004-0.058 mg/kg for Cd, 0.03-3.8 mg/kg for Cr and 0.0-0.03 mg/kg for As. Highest mean content of toxic trace element found in all vegetables was Zn followed by Cu. Cr and Pb contents in vegetables were higher than that of the Cd and As. However, except Pb in potato, none of the toxic trace elements exceeded maximum permissible levels imposed by the WHO/FAO Joint Codex Alimentarius (2001) indicating that most of the vegetables do not contain toxic elements above the MPL. Among nine vegetables, carrot (5.0mg/kg), beet (4.7mg/kg), potato (4.6 mg/kg), leek (3.8 mg/kg) and bean (4.0 mg/kg) showed significantly high contents of Zn than other vegetables tested and lowest was found in bitter gourd (1.55 mg/kg). Significantly high level of copper was found in leek (1.47 mg/kg) and brinjal (1.25 mg/kg) followed by capsicum (0.957 mg/kg) and potato (0.937 mg/kg). The lowest Cu content was observed in cabbage which was 0.32 mg/kg. Highest mean concentration of Pb (0.40 mg/kg) was observed in potato compared to other vegetables while the lowest content was found in bittergourd (0.009 mg/kg). It should be noted here that the mean content of Pb in potato observed was greater than the maximum permissible level imposed by Codex Alimentarius (2001).

Maximum Permissible Level for potato may have been established based on the dietary habit of Europeans as they consume large quantity of potato compare to Sri Lankans Hence, although, mean Pb content in potato exceeded the maximum permissible

TOXIC TRACE ELEMENTS IN VEGETABLES COLLECTED KANDY MARKIT 21 limit, there is no high tendency to exposure to Pb with potato for islanders as they consume lower quantity of potato than the Europeans. Bean, beet, cabbage, leek and capsicum also showed the presence of Pb contaminated samples. Therefore, it is necessary to pay attention to identify the possible sources of Pb contaminations in these vegetables.

Cadmium contents of vegetables varied from 0.001 mg/kg to 0.058 mg/kg. The highest mean content of cadmium was found in carrot (0.05 mg/kg) followed by beet (0.031 mg/kg) while the lowest cadmium content was found in capsicum (0.001 mg/kg).Chromium contents in tested vegetables varied from 0.03 mg/kg to 3.8 mg/kg. The highest mean Cr content was observed in carrot (0.97 mg/kg) followed by cabbage (0.88 mg/kg).Mean arsenic contents in all nine vegetables varied from 0.0 to 0.005 mg/kg. The highest As content was found in potato (0.005 mg/kg) and lowest was in capsicum (0.002 mg/kg).

Exposure of contaminants are usually expressed as provisional tolerable daily intake, a reference value based on body weight for an average adult (60 kg body weight) established by FAO/WHO (1999). The values were estimated assuming that each person is consuming 250 g of each vegetable. The estimated dietary intakes of toxic trace elements studied did not exceed Tolerable Daily Intake (TDI) levels stipulated by FAO/WHO (1999) and the maximum exposure via vegetables remains< 10% of the TDI except for Pb with potato. In the case of potato maximum exposure level reaches 48.6%. Hence, contamination of Pb through regular consumption of potato may pose a risk to the local population. Therefore, it is important to carry out periodic monitoring of Pb contents in potato and identification of sources of Pb contaminations in potato before it could become a problem.

REFERENCES

FAO/WHO.1999. Expert Committee on Food additives. Summary and Conclusion, 53 rd meeting Rome: Joint FAO/WHO, 1-10. FAO/WHO. 2001. Food additives and contaminants. Joint Codex Alimentarius Commission, FAO/WHO Food Standards programme. ALINORM 01/12A, Ghaedi, M., A. Shokrollahi, A.H. Kianfar, A.S. Mirsadeghi, A. Pourfarokhi and M Soylak. 2008. The determination of some heavy metals in food samples by Flame Atomic Absorption Spectrometry after their separation. Ghosh R., R. Xalxo and M. Ghoish. (2013). Estimation of Heavy Metals in Vegetables from Different Market Sites of Tribal Based Ranchi City Through ICP-OES and to Assess Health Risk. Current World Environment 8(30): 435-444.

22 SILVA et al.

Mc Bride, M.B., 2003. Toxic metals in sewage sludge amended soils: has promotion of beneficial use discounted the risks. Adv. Enviorn. Res. 8:5-19 Premarathna, H.M.P.L., G.M. Hettiarachchi and S.P. Indrarathna (2011). Trace metal concentration in crops and soils collected from intensively cultivated areas in Sri Lanka. Pediologist 230-240. United State of Environmental Protection Agency (USEPA METHOD3051) 1994. Revision 0 September: 1-14. Wijewardena, J.D.H. and U.W.S.P. Yapa (1999).Effect of the combine use of animal manure and chemical fertilizer on potato and vegetable cultivation in the up country of Sri Lanka. Sri Lankan Journal Agric. Sci. 36: 70-82. Heavy metal contents in commonly used animal manures, Annals of the Sri Lanka Department of Agriculture. 6: 245-253.

Annals of Sri Lanka Department of Agriculture 2016. 18: 23 - 45

MORPHOLOGICAL AND MOLECULAR CHARACTERIZATION OF TRICHODERMA ISOLATES USED AS BIO-CONTROL AGENTS IN SRI LANKA

R.G.A.S. RAJAPAKSE \ F.S. FARIZ 2, W.A.R.T. WICKRAMARACHCHI \ D.M.K.K. DISSANAYAKE M.P.T. PREMARATHNE 1 AND K.J.P.K. KAHAWATTE 1

1 Horticultural Crops Research and Development Institute, Gannoruwa, Sri Lanka 2 INTI International University, Malaysia.

EXTENDED ABSTRACT

A key element of sustainable agriculture is the ecological approach to solving the problems with plant pathogens by the application of Bio-Control Agents (BCA). Among the BCAs, Trichoderma spp. is the most intensively studied fungal species. Trichoderma spp. act as natural bio-control agents against several important phytopathogenic fungi and it is one of the best known mycoparasites that could be used as a bio-control agent against many soil-borne plant pathogens such as Fusarium, Rhizoctonia, Phytophthora, Sclerotinia, Alternaria (Agrilinks, 2013). Commercial use of Trichoderma BCAs must be headed by precise identification. Characterization and identification of strains at the species level is the first step in utilizing the full potential of fungi in specific applications. Morphological characterizations were used, however, several molecular biological techniques based on Polymerase Chain Reactions (PCR) have been used to detect and discriminate among microorganisms. Sequence analysis of the internal transcribed spacer (ITS) region has been helpful in the neotypification, description and characterization of species in the genus. Therefore, the objective of this research is to characterize the Trichoderma spp. phenotypically (based on cultural and microscopic observations) and genotypically at species level with sequence analysis of the Internal Transcribed Spacer ITS region for future use of producing large scale BCAs for Sri Lankan agricultural fields.

The six Trichoderma isolates identified as bio-control agents namely MAR1, MAR3, JAP, KON, HAR and VIR obtained from the culture collection at Horticultural Crop Research and Development Institute, Gannoruwa were used in this study. The morphological characterization and identification was performed based on the online interactive key provided by Samuels et al. (2015) which included the phenotypic characters classified under colony appearance, sporulation pattern, growth rate, size and shape of conidia/phialides/conidiophores, branching patterns of conidiophores and the appearance of chlamydospores. Treatments were six times replicated and arranged as CRD and incubated at 28 oC. Daily observations were made for 4 days. Lengths and

24 RAJAPAKSE et al. widths of conidiophores, phialide and conidia of the Trichoderma isolates were measured with a stereo microscope attached to a Nikon camera (Figure 1).The mean growth rates and the measurements of the Trichoderma structures were analyzed by MSTATC statistical software.

Molecular characterization was done with the DNA extracted from isolates of Trichoderma based on the Cetrimide Tetradecyl Trimethyl Ammonium Bromide (CTAB) extraction followed by PCR amplification with universal primers, ITS-1 (5’- TCCGTAGGTGAACCTGCGG-3) and ITS-4 (5’-TCCTCCGCTTATTGATATGC-3’) amplifying fragment of 600bp size.PCR program included an initial denaturation of 5 minutes at 94 oC, followed by 35 cycles of 1 minutes at 94 oC, 1 minute at 55 oC and 1 minute at 72 oC with a final extension at 72 oC for 10 minutes using a thermo cycler. The PCR products of the samples were sequenced and FASTA form of the result sequences were edited and analyzed using Basic Local Alignment Search Tool (BLAST). Multiple sequence alignment was then performed using Clustal W program. Phylogenetic dendogram was constructed by the neighbour-joining method and tree topologies were evaluated by performing bootstrap analysis of 1,000 data sets using MEGA 4.

When considering morphological characters, due to the homoplasy, it is often difficult to discriminate species and it requires a wide fungal taxonomical knowledge. According to the results, Trichoderma isolates exhibited significantly different rapid growth rates. The colony color changed from light green to dark green with the production of conidia after 48 hours. The conidial shapes were observed to be globose to subglobosein all cultures while oblong to narrowly ellipsoidal in KON. The phialide shapes were observed to be straight and ampulliform in all cultures while cylindrical in KON. Chlamydospores were present in all five samples except sample KON. Species of this genus produce a broad array of pigments from bright greenish-yellow to reddish in colour, although some are colourless. Therefore, species identification within this genus through pigmentation is difficult because of the narrow range of variation. Furthermore, the shapes of phialides and conidia were not applicable with the shapes of the known isolates. Nevertheless, the descriptions of the shapes of phialide and conidia were not categorically useful in identifying most of the isolates due to the confusion caused by the use of different terms in different literatures in describing the shapes of the phialide and conidia. Furthermore, noticeable differences in the sizes of phialides, conidia and conidiophores were observed in the cultures. There was a significant variation observed among the mean lengths and widths of the Trichoderma isolates. However, phialide and conidial sizes of these isolates were useful in narrowing down the possible number of Trichoderma species in the process of species identification (MAR1 = MAR3).The morphological characteristics were generally found to be highly variable as

MOLECULAR CHARACTERIZATION OF TRICHODERMA ISOLATES 25 morphological analyses are highly prone to error. Therefore, molecular techniques were used for 7 6 5 4 3 2 1 M characterization.

^■600 bp

The PCR products amplified an

Figure 1 . ITS region amplified using approximately 600bp fragment from all samples primer pair ITS1 and ITS4. (Figure 1) and after the sequencing process, Note: Lane M=1 kb marker; 1=MAR 1; phylogenetic trees were drawn for each isolate with 2=MAR 3; 3=JAP; 4=Water control; higly similar sequences. According to the BLAST 5=KON; 6=HAR; 7=VIR. and phylogenentic results,MAR3 showed 98% nucleotide identity with T. asperellum, JAP showed 100% nucleotide identity with T. asperellum, KON showed 98% identitiy with T. longibratiachum while HAR and VIR showed 99% nucleotide identity with T. asperellum. Based on the molecular analysis through ITS regions, among the 6 isolates, five were identified as T. asperellum and one as T. longibrachiatum . Morphology based technique was not very accurate when identification to species level was required.

ACKNOWLEDGMENT

The authors are grateful to all the staff members of the Plant Pathology Division, Horticultural Crops Research and Development Institute, Gannoruwa, Peradeniya for their support in conducting this study.

REFERENCE

Agrilinks. 2013. Production and Use of Biocontrol Agents Trichoderma and Pseudomonas. [on line]. [Accessed on 15.11.2014]. Available at http://www.agrilinks.org/events/ production-and-use-biocontrol-agents-trichoderma-and-pseudomonas.html. Samuels, G.J., P. Chaverri, D.F. Farr, and E.B. McCray. 2015. Trichoderma online, Systematic Mycology and Microbiology Laboratory, ARS, USDA. [on line]. [Accessed on 03.02.2015]. Available at http://www . nt. ars-grin. gov/taxadescriptions/keys/T richoderma Index.cfm

Annals of Sri Lanka Department of Agriculture 2016. 18: 26 - 27 SEED BORNE PATHOGENS ASSOCIATED WITH SEED LOTS OFMAJOR FOOD CROPS OF SRI LANKA

M.G.D.L. PRIYANTHA 1, A.R.J. ATHUKORALA 1, J.A.V.J. JAYASINGHE 1 M. SATO 2 AND H. TAKAHASHI 2

1 Seed Health Testing Unit, Gannoruwa, Peradeniya, Sri Lanka 2 National Centre for Seeds and Seedlings, Tsukuba, Ibaraki, Japan

EXTENDED ABSTRACT

Seeds contaminated with pathogens are responsible for the perpetuation, introduction, dissemination of a large number of diseases of cultivated crops, large reductions in yield, produce low quality seeds that affect their germination, vigour and storability conditions, and eventually affect nutritive value of seeds and increase cost of disease management. Identification and confirmation of the occurrence of seed borne pathogens of major food crops in Sri Lanka is very important to develop seed health testing protocols suitable to the island for rapid and quick detection of seed borne pathogens and to prioritize research activities on seed health and seed technology. Therefore, two studies were conducted with the objectives of finding out the prevalence of seed borne pathogens of selected food crops in Sri Lanka and to investigate the effect of rice seed borne pathogens on germination and seedling vigour.

Seed samples were tested for the presence of seed borne fungal pathogens using blotter test, agar plate method and paper towel method following the international rules for seed testing (ISTA) (Anon, 2013, and Mathur and Olga, 2003). Washing test, dilution and plating, agar plate method, bioassays were used to identify the presence of seed borne bacterial pathogens. Semi-selective media and immuno strips specific to certain bacteria were also used for the identification. Grow out tests, bioassays and ELISA were performed to identify seed borne viruses in suspected seed lots. The effect of seed borne pathogens on germination and vigour of rice seeds were studied using naturally fungi infected seed samples after confirming the infection level of each seed lot by blotter method. Seedlings obtained from germination tests were used to calculate vigour index.

Twenty seed borne pathogens were identified with 36 different crop-pathogen combinations during the period of March 2012 to March 2016. When considering the occurrence of seed borne pathogens in Sri Lanka, rice, other field crops and vegetable crops have been infected with major seed borne pathogens of high potential risk for subsequent crop and ability to cause severe crop losses. Seed infestation by seed borne fungi had a strong negative relationship with seed germination (R 2 = 0.847) and seedling vigour (R 2= 0.919). Fusarium sp. infected rice seeds showed maximum inhibition of germination followed by Alternaria and

MICRO PROPAGATION OF ANTHURIUM VARIETIES 27

Helminthosporium infected seeds. Fusarium sp. is known to invade the seed coat, endosperm and embryo resulting in failure in germination. This pathogen may contribute in part to poor seed germination and reduced rice stands in the field, where infected seeds have been planted. Alternaria padwickii was responsible for necrotic spots developed in roots and coleoptiles of seedlings. Heavily infected seedlings eventually die. This pathogen causes loss in germination, viability and vigour of rice seeds. The second most isolated pathogen is H. oryzae which reduces germination, shoot length, root length and vigour. All the isolated fungi in infected seeds caused significant reduction in shoot length and root length compared to those of the healthy seed samples. Among the isolated fungi, Fusarium sp. caused significant reduction in shoot length whereas the other tested pathogens caused significant reduction in root length.

Twenty different seed borne pathogens (14 fungal pathogens, 3 bacterial pathogens, and 3 viral pathogens) in a wide range of seed samples collected from different sources were identified and the pathogenicity was confirmed. Results revealed a strong negative relationship of rice seed infestation by seed borne fungi with seed germination and seedling vigour. Healthy seed samples gave maximum germination and the highest seedling vigour reflecting the importance of using healthy seeds for crop establishment.

REFERENCES

Anonymous, 2013. International Rules for Seed Testing Annexure to chapter 7 Seed Health Testing Methods. International Seed Testing Association (ISTA), Bassersdorf, Switzerland. Edition 2013. Mathur, S.B. and Olga Kongsdal, 2003. Common Laboratory Seed Health Testing Methods for detecting fungi. International Seed Testing Association, P.O. Box 308, 8303 Bassersdorf, CH-Switzerland: 71-334. PERFORMANCE OF BW RICE VARIETIES GROWN IN THREE DIFFERENT SOIL TYPES IN THE WET ZONE OF SRI LANKA

W.R.K.D.W.K.V. WICKRAMASINGHE, S.P.GUNARATHNE, D.M. JAYASUNDARA, H.A.I. SAJEEWANI, K.D.S. SAMARARATNE AND J.B.K. KANNANGARA

Regional Rice Research and Development Centre, Bombuwela, Sri Lanka

EXTENDED ABSTRACT Rice occupies approximately 33% of the total cultivated land extent in Sri Lanka accounting to 0.78 million ha (CBSL, 2010). It is grown under more diverse environmental conditions than any other food crop in Sri Lanka (Panabokke & Punyawardena, 2000). About 80% of the cultivated land extent of the Wet zone spread across in the Low Country Wet Zone (LCWZ). Rice sown extent under LCWZ is 73,226

Annals of Sri Lanka Department of Agriculture 2016. 18: 28 - 45

ha in Maha 2014/15 (Department of Cenusus and Statistics, 2015). Rice yield in LCWZ is comparatively low due to abiotic limitations such as salinity, iron toxicity, flash flood and poor drainage conditions. Soil types in LCWZ mainly divided in to two groups, namely, mineral and organic soil. Generally these organic soils lie in lower part of the catena and while upper positions of the catena occupy with mineral soils. Texture in upper catenal positions is rather varying. Since soil problems vary from location to location, it requires location specific cultivation packages including appropriate cultivars to increase the paddy yield in the LCWZ. Regional Rice Research and Development Centre (RRDC), Bombuwela has released 14 rice varieties until 2013 to address the issue of adverse soil and weather conditions of this region. However, these varieties do not perform equally well in different soil types in the region while some varieties are performing better in some soils than others. Therefore, this study was focused to identify suitable Bw rice varieties for three different soil types in the LCWZ where rice is the major land use.

Experiment was carried out in Yala 2014 , Maha 2014/15 and Yala 2015 at the research field of the RRDC, Bombuwela, located in the LCWZ. Three locations were selected in different parts of the research field according to soil texture and organic matter content (sandy, mineral and half-bog). Popular six Bw rice varieties Bw-372, Bw- 367, Bw-361, Bw-363, Bw- 267-3 and Bw-272 6/b and one Bg variety Bg-300 were used as test entries. Varieties were arranged in the field as a Randomized Complete Block Design (RCBD) and treatments were replicated three times in selected three different locations. Organic matter content and texture of the soil varied in selected three locations. Highest organic matter content (17-18%) was in half bog soil and it was located in lower part of the soil catena. The lowest organic matter content (4-5%) was found in upper catenal positions of the research field. Exchangeable K, available P and total N content in the soil were higher in the half-bog soil and lower in upper catenary positions in both seasons. Analysis of variance and mean separation showed that significant differences of yield (t/ha) among locations. Crop grown in half bog soil resulted in average yield of 3.94 t/ha than that of mineral soil with 2.8 t/ha average yield. The lowest rice yield was recorded in sandy soil (1.65 t/ha). Results also reveal that different varieties differently perform in each location. In half bog location, Bw- 367 (4.79 t/ha), Bw-372 (4.41 t/ha), Bw-267-3(4.18 t/ha) and Bw -361 (4.04 t/ha) performed well and gave the highest yield. In sandy soil location, Bw-372 (1.99 t/ha) resulted the highest yield followed by Bw-361 (1.94 t/ha) and Bw-363 (1.87 t/ha). Yield of all recommended Bw varieties performed equally well in mineral soil location and yields were not significantly different among them. However, Bg-300 resulted the lowest yields in all locations compared with the Bw varieties.

When considering Kalutara District, the total rice cultivation extent in Maha 2014/15 was 13,864 ha with over 53% of total sown with Bg varieties where only 27.1%

MICRO PROPAGATION OF ANTHURIUM VARIETIES 29 of the total sown extent was under Bw varieties. Considering the poor performance of Bg-300 despite its popularity among farmers, there is a potential to improve rice yield in LCWZ by increasing the extent under Bw varieties. This study reveals that Bw-372, Bw- 367, Bw-267-3 and Bw- 361 rice varieties are suitable candidate varieties for half-bog soil type and Bw- 372, Bw-361 and Bw-363 are well suited to the soils with sandy loam texture. Thus, it can be safely concluded that, Bw 372 and Bw 361 rice varieties are the most adaptable and productive LCWZ rice eco-system.

REFERENCES

Bentota, A.P., M. Faheim, B.G.D.S. Weerasinghe, C.A. Paranagama and T.N.A.W. Jayathilaka, 2013. Development and Performance of Released rice varieties to iron toxic rice soils in Sri Lanka. Tropical Agriculturist 161, 1-18. Chitranayana, R.D and B.V.R. Punyawardana. 2014. Adaptation to the vulnerability of paddy cultivation to climate change based on seasonal rainfall characteristics. Journal of National Science Foundation, Sri Lanka 42(2). 119-127 Jayawradena, S.N., M.M.P. Muthunayake and S.W. Abeysekara, 2010. Present Status of varietal spread of rice in Sri Lanka. Annals of Sri Lanka Department of Agriculture, 12, 247 -256.

30 PRERA et al.

Kendaragama, K.M.A 2000. Potential of our soils to feed the nation. Paper presented on the Seminar on Land and water management for Agriculture in the next millenium on april 67 at ISTI, Gannoruwa. Panabokke C. R and B.V.R. Punyawardane 2000. Rational utilization of land and water resource base of rice - paddy of Sri Lanka, Proceeding of the rice congress 2000, 13-14 December, Plant Genetic Resource Centre, Department of Agriculture, Gannoruwa, Peradeniya. P.39 Wickramasinghe W.A.D.B. and J.D.H. Wijewardana, 2001. Soil fertility management and integrated plant nutrition system in rice cultivation. www.agrilearning . goviya.lk/paddy/paddy_research/paddy-pdf1

Annals of Sri Lanka Department of Agriculture 2016. 18: 31 - 45

DIVERSITY AND CORRELATION AMONG AGRONOMIC TRAITS IN NEWLY IMPROVED RICE VARIETIES UNDER DRILING AND RANDOM BROADCASTING

T.K. ILLANGAKOON 1, J.M.N.P. SOMARATNE 1, S.S. PATHTHINIGE 1, R.S.K. KEERTHISENA 1, C.H. PIYASIRI 1, S.D. ABEYSUNDARA 1 AND I.H. THUSHARA 2

1 Rice Research and Development Institute (RRDI), Batalagoda, Sri Lanka 2 Faculty of Agriculture, University of Ruhuna, Mapalana, Kamburupitiya, Sri Lanka

EXTENDED ABSTRACT

The newly improved rice varieties (NIVs) cover more than 99 % of the cultivated extent of Sri Lanka and have contributed to increase the average yield up to 4.4 t/ha in 2014 (Department of Census and Statistics, 2015). In addition to poor yields recorded in minor irrigation and rainfed cultivations, a significant yield gap exists due to the fact that inability of farmers to exploit the yield potentials of NIVs attributing to improper crop management practices (Dhanapala, 2000). The target of increasing the average national paddy productivity up to 5 t/ha by the year 2018 can be achieved by exploiting maximum yield potential of existing rice varieties and adopting improved technologies. This study attempts to create a useful data base by identifying the diversity and correlation among agronomic traits of 44 NIVs in Sri Lanka under two direct seeded methods, drilling and random broadcasting.

The experiment was conducted at the Rice Research and Development Institute (RRDI), Batalagoda, Ibbagamuwa, Sri Lanka during Maha 2013/14 and Yala 2014. Forty four NIVs belonging to four different age groups; viz. 4‘A, 4, 3‘A and 2*A-3 months were tested in a split plot design with three replicates. The main plots were assigned to establishment methods; drilling and random broadcasting and the sub-plots were assigned to varieties. Drilling was done manually with a spacing of 20 x 15 cm. Three to four pregerminated seeds were drilled about 0.5 cm depth at seeding and extra seedlings were removed two weeks after seeding to keep a single seedling/hill. In random broadcasting, pre-germinated seeds were sown by taking the required amount of seeds calculated based on thousand grain weight of each variety to have a seed density of approximately 400 seeds/m 2. Agronomic traits including maximum number of tillers/plant, plant height, leaf length, leaf width, total number of leaves/plant, days to panicle initiation, 50 % heading, physiological maturity, number of panicles/plant, grain yield, panicle length, panicle weight, number of grains/panicle, filled grain percentage, thousand grain weight and yield were recorded. Total leaf area/plant and harvest index were calculated by following the methods described by Yoshida (1981).

32 ILLANGAKOON et al.

Significant differences were observed between establishment methods and among the varieties for all traits tested within the same age group in both seasons. Number of tillers/plant, number of leaves/plant, leaf area/plant, leaf length, leaf width, plant height, number of panicles/plant, panicle length, panicle weight and number of grains/panicle were significantly higher in drilling compared to random broadcasting in all age groups. Days to panicle initiation, heading and physiological maturity delayed by 2-5 days in drilling due to extended vegetative growth. There was a yield increase in drilling for 4% and 4 months age groups but in 3% months and 2% - 3 months age groups, yield was high in random broadcasting. Harvest index had an inverse relationship with increasing age.

The dendrogram derived using the data obtained in all traits in drilling in Yala 2014 exhibited five dissimilar clusters indicating a presence of considerable diversity among the NIVs. Panicle initiation and heading dates had strong positive correlations with maturity dates (r=0.93 and 0.97, respectively). A positive and significant correlation of plant height with panicle length, panicle weight and grain number/panicle suggesting that tall varieties bear long panicles with more grains. Yield correlated positively with tiller and panicle numbers, plant height, leaf length, leaf width, leaf number, leaf area, days to panicle initiation, heading, maturity, panicle weight, panicle number and grains/ panicle while maturity date gave the highest positive correlation towards the yield (r =0.49). This indicates that late maturing varieties have higher yield potentials than early maturing varieties.

Based on results of drilling method of establishment in both seasons, some of the varieties having beneficial agronomic characters were listed in the Table 1. Varieties having high tillering ability are suitable for machinery transplanting since they cover the ground within a short period of time. The high yielding varieties mixed with other important agronomic traits can be used to increase the productivity of paddy lands with combination of suitable management technologies.

It is concluded that vigorous plant growth and a higher yield can be achieved by practicing drilling compared to random broadcasting for medium age varieties. Among the NIVs tested, Bg 454 and Bg 406 have the highest yields. Bw 451 and Bw 363 have the highest grain number/panicle (343) and the highest value for harvest index (0.6),

CORRELATION AMONG AGRONOMIC TRAITS IN NIVs 33 respectively. Yield increases with many agronomic traits, but age is the most important factor contributing to high yield.

Table 1: Promising varieties identified with desirable agronomic characters.

Trait Varieties Tiller number > 15/plant Bg 454, Bg 450, Bg 11-11, Bg 400-1, Bg 379-2, Bg 403, Ld 408, At 405 Panicle number > Bg 454, Bg 450, Bg 400-1, Bg 403, Bg 379-2 10/plant Panicle:tiller ratio> 0.8 Bg 379-2, Bg 360, Bg 357, Bw 351, Bg 369, At 362, Bw 367, At 308, At 307, Bg 250 Panicle weight >5g Grain Bw 400, Bw 451, Bw 367, Bg 400-1, Bg 358, Bg 369 Bw 451, Bg number> 250/panicle 450, Bg 11-11, Bg 369, Bw 367 Yield >6t/ha

Harvest index > 0.55 Bg 454, Bg 450, Bw 451, H 4, Bw 453, Bw 452, Bg 379-2, Ld 408, Bg 406, Bg 357, Bg 366 Bg 403, Bg 354, Bw 363, At 362, Ld 365. Bg 357. Bw 363, Bg 352, Bg 94-1, At 354, Bg 300, Bg 305, Bg 304

ACKNOWLEDGMENTS

Authors wish to acknowledge Dr. A.P. Bentota, Director, Mr. D.N. Sirisena, Deputy Director (Research) and all the staff in Agronomy Division of RRDI for their support provided to carry out this study.

REFERENCES

Department of Census and Statistics. 2015. Paddy Statistics. Colombo, Sri Lanka. [on line].[Accessed on 06.04.2016]. Available at http://www.statistics.gov.lk . Dhanapla, M.D. 2000. Bridging the yield gap in Sri Lanka. Paper presented at expert consultation on bridging the yield gap in the Asia-Pacific region. Ed. Minas K. Papademetriou. FAO Publication. 2000/16, Bangkok, Thailand. October 5-7, 1999. Yoshida, S. 1981. Fundamentals of rice crop science. International Rice Research Institute, Los Banos, Philippines. 22-23, 61.

Annals of Sri Lanka Department of Agriculture 2016. 18: 34 - 45

INCOME DIVERSIFICATION AMONG MEMBER’S OF FARM WOMEN ORGANIZATION IN AMPARA DISTRICT

AT. SOORIYAARACHCHI R.A.K. KALYANI 2 AND H.U. WARANAKULASOORIYA 2

1 Field Crop Research and Development Institute, Mahailluppallama, Sri Lanka 2 Socio Economic and Planning Centre, Department of Agriculture, Peradeniya, Sri Lanka

EXTENDED ABSTRACT

Income diversification is an important factor in household economies for sustainable livelihoods (Reardon, 1998). Age, number of years of education, female headed households, household income per capita, number of extension visits, productive assets owned and natures of road were found to be significant in determining income diversification of farm households (Agyeman et al., 2014). The main objective of this study is to determine factors influencing income diversification among farm women organizations (FWO) in Ampara districts. Specific objectives are to estimate Simpsons index of diversity, and to study the relationship between income diversity with socio economic factors.

Data were collected from pre tested structured questionnaire were used in multi stage random sampling method for selection of 111 members of farmer women organizations in three agrarian services centre areas at Ampara district. This study used Simpsons index of Diversity (SID) that introduce by Simpsons in 1949 for estimation of income diversification (Agyeman et al., 2014). The Censored Tobit regression model (Greens, 2003) specification is used to identify the factors which determine farm household engagement in income diversification. The explanatory variables are given Table 1.

The mean degree of income diversification was found as 0.346 (34%). Member’s of farm women organization mean monthly income was Rs 34,407. Permanent (51%) and Agriculture (37%) income categories had higher contribution to household income compared to NFI (5%), temporary (4%) and other income (2%) categories.

According to the maximum likelihood estimation result of the Tobit model shows; the non farm income coefficient estimates are positive and highly significant. Income diversity index increases with increases with NFI. Member’s age of farm women

INCOME DIVERSIFICATION OF MEMBERS OF FARM WOMEN ORGANIZATION 35

organization was statistically significant with negative sign as expected and in agreement with Agyeman et al. (2014). Table 1: Variables used in Tobit model. Variable Name of Variable -Description Xi Age -Age of farm women (years) x2 Education -Use scale (no literate =0, literate no school attend =1, up to grade 5=2 up to 0/L=3, up to A/L =4, above A/L =5) x3 Per capita land -Area of land (ac) x4 participate society activities -Participate or not ( yes=1, no=0) Aj Participation number society -Number society involve A' fi Non -farm income -Non farm income of household (Rupees per month) A' - Distance to market -Distance to market (km) Ag Experience -Number of years

X9 Access to credit '-Access of credit ( yes =1. no =0) A'lo Household decision participation index -Use scale women empowered =1, not =0 Xn Trainings -Yes=1 no =0 A] 2 Social participation index -Social empowered =1, no=0

Note : In household decision participation index (HDPI): One point each was given if the women decided (individually or joint with others) about household expenses, child education, purchasing or selling household asset, savings, investment of money, health care of family and other important household decisions. A women with a score of four or better was classified as household empowered. In social participation index (SPI) - One point each was given if the women decided participate farm women organizations activities, attending social societies meetings, participating in decision making in social organization and decision on attending social events, A women with a score of two or better was classified as socially empowered.

These results imply that the diversity of income decreases with age. Women empowerment was statistically significant in household and social level index with positive and negative sign. This shows that income diversity index increases with more contribution from women in household activities compare to social activities. Participations of FWO activities and training showed a significant positive relationship. Similar observation was made by Khatun and Roy (2012). Income diversification showed an increase with increase in participation of FWO activities and training. According to respondents, the FWO member can be strengthened by providing trainings (80%), providing inputs (18%) and providing loan facilities (2%). They expected trainings on home gardening (24%) self- employment (48%), food processing and value addition (15%) and other industrial training (13%).

An opportunity increased in young women group target training program on

36 SOORIY AARACHCHI et al.

NFI activities and empower women in household activities was lead to increase income diversity.

REFERENCES

Agyeman, B.S.A., A. Samuel and E.O. Edward. 2014. Determinants of Income Diversification of Farm Households in the Western Region of Ghana. Quarterly Journal of International Agriculture 53: 55-72. Greens, W. 2003. Econometrics Analysis. Prentice Analysis, New Jersey. Khatun, D. and B.C. Roy. 2012. Rural livelihood diversification in West Bengl: Determinants and constraints. Agricultural Economics Research Review, 25: 115-124. Reardon, T. 1998. Rural non-farm income in developing countries. The State of Food and Agriculture: 283-356.

Annals of Sri Lanka Department of Agriculture 2016. 18: 37 - 45

A PROMISING MULTIPLIER ONION (ALLIUM CEPA) LINE WITH FIELD RESISTANCE TO MAJOUR FUNGAL DISEASES AND POSSESING MODERATE FLOWERING EFFICIENCY

S.J. ARASKESASRY 1, B. BOWLEESWARAN 2, P. ATPUTHACHANDRAN 3, S. HEARTH 1 AND B.G.R.C. BALASOORIYA 1

1 Regional Agriculture Research and Development Centre, Kilinochchi, Sri Lanka 2Agriculture Research Station, Thirunelvley, Sri Lanka 3 District Agriculture (Extension) Office, Mullaithivu, Sri Lanka

EXTENDED ABSTRACT

As other vegetable crops, Cluster onions are also susceptible to various foliar, bulb and root diseases caused by fungal pathogens that influence Cluster onion yield and quality in Sri Lanka. Anthracnose caused by Colletotrichum gloeosporiodes, Purple blotch of Cluster onion caused by Alternaria porri and bulb rot caused by Phytopthera spp. are threaten disease for cluster onion. At present, there is no resistant Cluster onion variety/ hybrid for these major fungal diseases in commercial cultivation in Sri Lanka. As there is a need to breed/select a resistant or tolerant variety to increase the bulb production and/or to increase true seed availability a series of studies were re-conducted since the year 2002 at the Agriculture Research Station (ARS), Thirunelvelly to expand the genetic pool, create diversity and to include in to hybridization program. This paper extracts research information from these studies conducted during recent past at ARS, Thirunelvelly and Regional Agriculture Research and Development Centre (RARDC), Killinochchi, in Northern Province of Sri Lanka to evaluate agronomic traits and to screen against aforesaid important fungal diseases.

Few promising cultivars were grouped in to two different classes as shallots and multipliers and these were named serially as Thirunelvelly Shallot (TVS) for shallot types and Thirunelvelly Multiplier (TVM) for multiplier types irrespective of their identities. Then agronomic traits of TVM series were evaluated in different years for bulb number per plant, bulb weight per plant, days for maturity and the bulb yield. Raised beds of 3.75 m x 0.6 m, check basins of 1 m x 1 m and Randomized Complete Block Design (RCBD) with three replications were used for all replicated trials. Agronomic practices of field experiments were carried out as per the DOA recommendations. A total of 30 germplasm were used in these studies. The field was sprayed with a spore suspension of Colletotrichum gloeosporiodes 10-days after planting for screening of Anthracnose. For bulb rot screening, sick plot technique was used .Observations on disease severity for anthracnose and bulb rot were recorded on a 0-7 scale at 10-day intervals and disease Severity Index (DSI) was calculated in percentage using 1-7 scale.

38 ARASKESASRY et al.

Twelve promising entries identified out of initial 27 germplasm, were separated in to two major groups as shallots and multipliers having six in each groups. As the aim of this paper is to focus on the performances of multiplier line, namely, Thirunelvelly Multiplier No. 6 (TVM-6) which possesses high yielding ability, high flowering response and favourable fungal disease resistant responses, further discussion is focused towards the performance of this particular line in comparison with the other few entries in the same group in a series of experiments conducted in different locations. In these experiments, shallots had more bulb number per cluster, less number of days to maturity, less single plant yield while the multipliers had opposite performances for each of these parameters. TVM-6 that comes under multiplier group had 156 and 55.5 grams, 12 and 6 bulbs per plant, 12.9 and 4.9 grams single bulbs, 79 and 68 numbers of days to maturity and 33.4 and 32.3 t/ha yield in both Maha and the Yala seasons, respectively. In replicated trials, all these germplasm had significance differences among each other and TVM-6 had the second highest rank in number of bulbs in two Maha seasons and the third rank in the Yala season. The bulb number per plant varied from 11-13 in Maha season. The days to maturity were higher in Maha seasons and low in Yala seasons. The average yield performance of this TVM-6 in eight consecutive seasons was 26.83 and 28.57 t/ha with the maturity of 71 and 67 days in Maha and Yala seasons, yield of other entries varied significantly with TVM-6 which gave with an average yield of 27.7 t/ha in both seasons. Days to maturity were around 69 days on average. The TVM-6 resulted in more than 20 t/ha, while all others with comparatively lower yields when there was a severe incidence of Anthracnose disease in Maha 2009/10 at ARS, thinnavely. Thus, TVM-6 has a potential of yielding more bulbs even under disease conditions.

In a study conducted with 12 entries at ARS, Thirunelvelly in 2013/14 Maha season, TVM-6 showed moderate resistance to Anthracnose disease (12%) with fungicides spray free conditions. The other entries TVS-3, TVS-6, Jaffna local and TV cluster also gave similar results. Resistance or tolerance of the shallots types are to be attributed to their short duration nature which normally escapes from the heavy infection period of fungal disease. Among the multipliers, the TVM-6 showed the lowest disease incidence and showed moderate resistance behaviour for bulb rot with only 8.5 percentages of rotted bulbs and this entry had the lower bulb rot incidence while shallot as usual had very low values of the bulb rot incidence. In contrast, a study conducted at RARDC, KC with 30 entries of cluster onion for anthracnose screening during 2014/15 Maha season has revealed that out of these 30 lines the only candidate line that showed a moderate resistance behaviour (20%) was TVM-6 while the others ranged from highly susceptible to moderately susceptible even with complete damage of foliage due to high incidence of anthracnose. TVM-6 performed relatively commendable higher degree of tolerance to Anthracnose disease

In Yala few tested entries flower only with vernalaization with significance

PROMISING MULTIPLIER ONION LINES RESISTANCE TO FUNGAL DISEASES 39 differences among them .TVM-6 had the highest response for vernalization and gave 18.3 percent plants with flowering. Though all flower in Maha season except TVM-6 showed susceptibility or high susceptibility for both anthracnose and bulb rot disease. Thereby the TVM-6 produced more productive flowers (48%), and yielded with seeds in recent studies. As per agronomic performance, yield abilities, resistance to anthracnose and bulb rot disease of various cluster onion lines in different seasons and the locations the newly identified cluster onion line TVM-6 has high potential to be used as a new variety after conducting varietal adaptability trials or it could be used as a reliable breeding material for future cluster onion breeding programme by which we can incorporate the desirable traits such as high yielding abilities, resistance to major diseases and to increase flowering efficiency for true seeds production in Sri Lanka.

REFERENCES

Araskesary, S.J., S. Gobigeetha and B.G.R.C. Balasooriya. 2014, Characterization and agronomic evaluation of cluster onion (Allium cepa L.) Landraces grows in Jaffna district, book of abstrat: SLCARP International Agricultural Research Symposium, 2014. Sri Lanka Council for Agricultural Research Policy, 11-12 August, Colombo, and Sri Lanka. Pp 09

Simanaratne, J.P., W.L.G. Samarasinghe, A.S.M.W. Wanigadeva, I.A. Gunasekara, and L.G. Sujeewakumari. 2005, Characterization of onions (Allium cepa L.) by morphological traits, isosymes and randomly amplified polymorphic DNA markers, 2005. Annals of Sri Lanka Departments of Agriculture 7: 253-270.

Annals of Sri Lanka Department of Agriculture 2016. 18: 40 - 45

EFFECT OF NATURAL AND ARTIFICIAL DIETS ON THE LIFE HISTORY PARAMETERS OF MELON-FRUIT FLY, BACTROCERA CUCURBITAE (DIPTERA: TEPHRITIDAE)

P.H. RANAWEERA 1, L.D. GALANIHA 1, M. RANATHUNGA 1, K.M.D.W. P. NISHANTHA 1, M. SIRIWARDANA 1 AND L. NUGALIYADDE 2

1 Horticultural Crops Research and Development Institute, Gannoruwa, Peradeniya, Sri Lanka 2 Sri Lanka Organizations of Agriculture Professionals, Formerly Faculty of Agriculture, University of Ruhuna, Sri Lanka

EXTENDED ABSTRACT

The tephrid fruit flies of the genus Bactrocera, with more than 500 species currently described as important pests of a number of fruit and vegetable crops. These fruit flies are among the most economically important pest species in the world (Kumar et al., 2011; Bandara and Billa, 2015; Vargas et al., 2015). Among the known melon-fruit flies, Bactrocera cucurbitae (Coquillett) is considered as the major threat to cucurbits resulting significant yield losses and quality losses inappropriate for local and export market. The magnitude of losses varies from species to species which may range from 30 to 100% depending on the cucurbit species and season (Dhillon et al., 2005). Recommended methods of pre-harvest control programme for fruit and melon flies include; use of protein bait, male annihilation with pheromones, biological control, fruit bagging, early harvesting, and orchard sanitation. Application of Sterile Insect Technology (SIT) as a component of IPM is new to Sri Lanka but, implementation of such technology programme is important because it is considered as an ecologically safe procedure. Mass rearing of insects for sterilization and release requires protocols for the production of insects that are behaviourally and physiologically similar to those of the natural population.

Therefore, in this study, five larval diets (Thailand , Mauritius, Standard and Liquid and NPQS ) were tested to determine the efficient medium for mass rearing of melon fruit fly (Bactrocera cucurbitae), as compared to four natural foods; Pumpkin, Bitter gourd, Snake gourd and Cucumber. Experiments were conducted at the Insectory, Horticultural Crop Research and Development Institute, Gannoruwa, Peradeniya from 2015 to 2016. During the study period, the average air temperature and Relative Humidity (RH) in the insectory ranged between 27-29 0C and 70-77%, respectively, and the photoperiod was maintained at Light: Dark - 9: 15 hours. Bactrocera cucurbitae eggs for the experiments were obtained from egg-laying devices kept in B. cucurbitae rearing cages in the insectory. B. cucurbitae eggs were inoculated on 250 g of natural diets and 50 g/dish artificial diets at the rate of 15 eggs/treatment. Mature larvae emerged from fruit were kept on sterilized sand (sterilized at 120 0C for 2 hours) for pupation. Pupae were sieved with a plastic mesh (18 meshes) and weighed. The experiment was replicated five times. The incubation period and hatching percentage of

PROMISING MULTIPLIER ONION LINES RESISTANCE TO FUNGAL DISEASES 41

eggs and larval duration in each diet were recorded. The procedure adopted under natural diet and artificial diets were followed to determine the pupal weight, pupal duration and adult emergence and sex ratio. The emerging adult flies were fed with protein hydrolysate and a mixture of sugar and water (1:1 v/v) soaked in cotton. Using the standard procedures (Chang et al, 2007) the following biological parameters of B. cucurbitae reared on diets were assessed; egg hatchability and incubation period, larval and pupal durations, pupal weight, percentage of pupal yield from larvae, percentage adult yield from pupae. All the percentage values check for normality and were log-transformed. The data of tested parameters were analyzed using ANOVA Statistical Analytical Software (SAS) Version 8.1. Tablet: Ingredients of the larval diets (for 1 litre) its pH value and Cost p er litre. Ingredient Artificial Larval Diets Mauritius NPQS Thailand Standard Liquid Sugar (g) 50 82.8 120 162 121.8 Brewer’s Yeast (g) 35 40 36 80 204 Wheat Bran (g) 175 351.4 260 242 - Wheat Germ Oil (ml) - - - - 2 C. HCl (ml) 1 8 2 - - M.P.H. Benzoate (g) 0.75 - - - - Sodium benzoate (g) 0.75 2 1 5 2 Tissue Paper (g) 25 - - - - Water (ml) 650 650 580 505 1000 Citric Acid (g) - - - 6 23.1 Nipagen (g) - 1 1 - 2 PH 4.5 -4.9 5 5 4.8 3.5 Cost/ L (SLR) 1,621/ 2,595/ 1,854/ 3,319/ 8,436/

1 The life history parameters of B. cucurbitae larvae reared on artificiall diet and natural diets did not show significant differences except in larval and pupal durations. The tested natural and artificial diets except liquid diet found to provide favourable conditions for egg hatchability (range 61.3-90.5%). Incubation period was ranged between 3.6-5.4 days. The percentage pupal recovery in natural and artificial diets (except standard and liquid diets) tested ranged from 71-97% and was not significantly different to each other. The larval period in artificial diets was longer (7.8a) as compared to natural diets (4.8 b). High male to female ratio was observed on Thailand diet (2.5: 1) compared to other diets which recorded from 1.5 to 1 male: 1 female. We observed that

42 RANAWEERA et al.

eggs did not hatch when incubated in liquid diet and larvae did not survive in standard diet, therefore these two diets considered as poor performers in B. cucurbitae rearing. The rest of the artificial diets performed similarly in terms of hatchability, incubation period, pupal recovery and pupal weight, pupal duration and adult emergence. High perish ability nature of natural diets can be used as initial stock for culturing B. cucurbitae. Therefore, NPQS diet, Mauritious diet and Thailand diet can be use for mass rearing as larval diets. But, Thailand diet is considered as the best in terms of the high male ratio. NPQS diet and Thailand diets are selected on the basis of the cost factor and high male ratio for the use of mass rearing of B. cucurbitae to introduce Sterile Insect Technology (SIT) program in Sri Lanka.

REFERENCES

Bandara, K.A.N.P. and M.K. Billa. 2015. Parasitoids/predators and alternative hosts of economically important fruit fly pests of low, mid and high elevations of Sri Lanka. Annals of Sri Lanka Department of Agriculture, 17: 303-309. Chang, C.L., C. Caceres and S. Ekesi. 2007. Life history parameters of Ceratitis capitata (Diptera: Tephritidae) reared on liquid diets, Annals of Entomological Society of America 100, 900-906. Dhillon, M.K., R. Singh, J.S. Naresh and H.C. Sharma. 2005. The melon fruit fly Bactrocera cucurbitae: a review of its biology and management. Journal of Insect Science 5:40. Kumar P., Abubakar, Alma Cinda, Ketelaar and T.W. Shanmugam. 2011. Field exercise guide on fruit fly integrated pest management. Asian fruit fly IPM project, Asia Institute of Technology, Bangkok, Thailand. Vargas R.I., J.C. Pinero and L. Leblanc. 2015. An Overview of pest species of Bactrocera fruit flies (Diptera: Tephritidae) and the integration of biopesticides with other biological approaches for their management with a focus on the pacific region. Insects 6: 297- 319.

Annals of Sri Lanka Department of Agriculture 2016. 18: 43 - 45

DEVELOPMENT OF A READY TO SERVE “EMBUL” BANANA BEVERAGE AS A VALUE ADDED PRODUCT

R.A.A. RANATHUNGA, G.T.N. GUNASEKARA AND W.A.K. KARUNATHILAKA

Grain Legume and Oil Crops Research and Development Centre, Angunakolapallessa, Sri Lanka.

EXTENDED ABSTRACT

Banana ( Musa accuminata L.) is one of the most widely grown fruits over 170 countries along the tropic and sub-tropics. In Sri Lanka, banana is the major fruit crop which is grown throughout the country. Banana cultivation extent of Sri Lanka is 53,628 ha with an annual national production of about 454,056 t (AgStat, 2012). After ripening, banana fruit is highly susceptible to deterioration. A considerable percentage of the harvest is wasted due to lack of efficient processing techniques that are unique to ripen banana. A very few processed products of banana are available in the local market, primarily due to difficulty in retaining the characteristics colour, flavour and texture during the processing of ripen banana (Bhalerao et al. , 2009). Making juice out of banana has been a difficult task due to its high susceptibility to fermentation and spoilage, especially in tropical climatic conditions owing to high temperature regime (Kyamuhangire, 1990). Hence, there is a timely need to develop and process banana juice in to stable products that can be readily available in the market. There is no banana related processed food products such as Ready to Serve (RTS) products in Sri Lanka. Hence, this study was undertaken to develop a methodology to extract “Embul” banana juice and to develop a RTS banana beverage.

Well matured Embul banana were ripened naturally and four ripening stages were selected to extract banana juice. Ripening stage three, four, five and six were used according to banana ripening colour chart. Then, sample of each ripening stage was blanched with hot water at 80 °C for one and half minutes, peeled off and cut in to 1.5 cm thick slices. Then, sliced banana pieces were put in to a mechanical blender and operated at medium speed until the juice is extracted. Subsequently, whole mixture was squeezed and filtered further by using sieve of 25 ^m to separate sediments. The experiment was done completely randomized design (CRD) with three replicates. Blanching time and temperature determination was conducted with six treatments with two factor factorial with three replicates. The treatment combinations were two levels of temperature (80°C and 90 °C) and three levels of time (1 min, 11/2min and 2min) were used. Ready to Serve drink was developed by diluting banana juice with different proportion of potable water. Fruit juice to water ratio were as follows, 1:1, 1:2 and 1:3. After dilution, two drops of sunset yellow colour, citric acid (1 g/l), preservative (0.3 g/l Sodium Metabi Sulphate) and sugar were added. Sugar was added to bring TSS level at 24° Brix. Then, the product was pasteurized at 80 °C for 20 minutes. Subsequently, RTS was poured into a sterilized bottle and sealed with a crown cap. As chemical properties, pH, total soluble solid, titratable acidity were measured. Sensory evaluation was done

44 RANATHUNGA et al.

with five points hedonic scale (1 as the extremely dislike and 5 as the most like) by a panel comprising 10 individuals. Shelf life study was carried out for three months by monitoring changes of pH and TSS. Statistical analysis was done by using SAS 9.1 version and SPSS 16.1 version.

In this experiment, ripening stage three, four and five resulted in sufficient amount of juice and only ripening stage six did not give any juice yield and it gave only the banana pulp (Table 1). As per the statistical analysis, juice recovery at ripening stage 3, 4, and 5 were statistically different (p<0.05). Stage 5 was the best ripening stage for extracting “Embul “ banana juice where 61.4% of juice recovered and followed by ripening stage 4 and 3 where 53.2% and 48.4% juice could be recovered, respectively

Table 1: Percentage juice recovery from Embul banana at different stages of ripening. Ripening stages Weight of banana ( g) Juice volume (ml) Juice recovery efficiency (%) Ripening stage 3 368.7 178.3 48.4c Ripening stage 4 358.6 192.7 53.2b Ripening stage 5 353.6 217.7 61.5a Ripening stage 6 324.1 NR NR

Note: Within the column, the means followed by the same letter are not significantly different at p=0.05. **NR-Not Recorded

Total soluble solid at ripening stage 3 was significantly (p<0.05) low compared to stage 4 and 5. Titratable acidity was significantly (p<0.05) high in ripening stage 3 and 4, while acidity was low in ripening stage 5. There was a significant (p<0.05) difference in sugar to acid ratio of extracted juice among ripening stages 3, 4 and 5. Meanwhile, there was no significant (p<0.05) difference in pH of extracted juice among the ripening stages.

The results showed that there was a time and temperature effect on juice yield. The highest juice yields of 50.6% and 51.4% obtained in two combinations of time and temperature were 1 and 1/2 minutes at 80°C and 1 minute at 90°C, respectively. Chemical parameters were not changed significantly with the time and temperature combination.

DEVELOPMENT OF A READY TO SERVE “EMBUL” BANANA BEVERAGE 45

The analysis revealed that RTS with 1:1 dilution (Banana juice extract: water) had the highest preference for taste and overall acceptability. Chemical properties such as TSS, pH and titratable acidity were 24.5, 4.2 and 0.73% respectively. Shelf life study was done at two weeks interval for three months. There were no significant changes in the chemical properties with the time suggesting that there is no spoilage during the tested time period.

Table 2: Chemical properties of “Embul” banana juice extracted using different stages of ripening. Ripening stage Acidity (%) Total Soluble Solid pH Sugar:Acid

Ripening stage 3 0.84a 17.0b 4.8a 20.3c Ripening stage 4 0.81a 20.6a 4.7a 25.5b Ripening stage 5 0.71b 21.2a 4.8a 30.0a Ripening stage 6 NR NR NR NR

Note: Within the column, the means followed by the same letter are not significantly different at p=0.05.

Ripening stage five was the best ripening stage to extract more banana juice yield than other ripening stages. Blanching temperature was also influenced the juice yield with the time where 90°C at 1 minute resulted the higher juice yield. “Embul” banana beverage having formulation 1:1 dilution was found to be the optimum mixing ratio among the formulations tested and can be stored safely for three months. Therefore, it can be concluded that the extracts of the “Embul” banana juice with a foresaid specifications can be used as a valuable RTS for commercial purposes.

REFERENCES

Bhalerao, V.P., N.M. Patil, C.D. Badgujar and D.R. Patil. 2009. Studies on integrated nutrient management for tissue cultured ‘Grand Name’ banana. Indian.! Agr .Res. 43: 107-112.

Kyamuhangire,W. 1990. Banana Juice Extraction and Processing. Doctoral thesis, University of New South Wales, Kensington.78.

Annals of Sri Lanka Department of Agriculture 2016. 18: 46 - 49

EFFECT OF DIFFERENT PSIDIUM ROOTSTOCKS ON THE CONTROL OF ROOT KNOT NEMATODE AND GROWTH AND YIELD OF GUAVA (PSIDIUMGUAJAVA L.)

E.R.S.P. EDIRIMANNA 1, R.G.A.S. RAJAPAKSE 2, A. WEERAWARNA 3, S. PUSHPAKUMARI 4, B.G. AMRASENA 1 AND T. KIRINDE 1

1 Fruit Crops Research and Development Station, Gannoruwa, Peradeniya, Sri Lanka 2 Horticultural Crops Research and Development Institute, Gannoruwa, Sri Lanka 3 Agriculture Research Station, Kalpitiya, Sri Lanka 4 Fruit Crops Research and Development Institute, Horana, Sri Lanka

EXTENDED ABSTRACT

Guava (Psidium guajava L.) is one of the important fruit crops grown in Sri Lanka. However, in recent years,the extent and production is gradually decreasing due to decline symptoms such as purple browning of leaves, growth inhibition, leaf drop, and death of the plants. These symptomatic seedlings found to have infected with root-knot nematode Meloidogyne spp. (Rajapakse et al., 2015). The damage was widespread across the country and all guava varieties were reported to be susceptible. The use of resistant rootstocks is a promising method to control Meloidogyne if guava-compatible genotypes can be found. Two Psidium spp. i.e. Psidium friedrichstalianium (Costarican guava) and P. cattleianum (Chineese guava) are reported as resistant to guava root-knot nematode (Freitas et al., 2014). Therefore, the present research aimed at verifying grafting compatibility between guava and other Psidium spp. at the stage of nursery production and post-planting in the field.

Studies were conducted at the Fruit Crops Research and Development Station (FCRDS) at Gannoruwa and Agriculture Research Station (ARS) at Kalpitiya, Sri Lanka, during 2012-2016. In first experiment, seeds of three Psidium spp. namely, P. guajava, P. friedrichstalianium and P. cattleianum were obtained from the orchard of the FCRDS and planted in a sand bed nursery. Two weeks after germination, plants were transferred to black polythene bags and were maintained up to the grafting size for about 8 months, by following recommended practices of Department of Agriculture (DOA), Sri Lanka. These plants were cleft grafted and patch budded using scion of two recommended guava varieties Bangkok Giant and Horana Rosi and one selection of guava ‘Gannoruwa selection’. In each treatment, 10 pots were used and the experiment was arranged in a Randomized Complete Block Design (RCBD) with five replicates. Data were recorded on the percentage grafting success and growth of the scion wood after grafting. The second experiment was established at the FCRDS at Gannoruwa to investigate the growth and yield of plants established using different planting materials namely, seedlings, air layered plants, and grafted plants to rootstock of P. friedrichstalianium and P. guajava. Planting materials developed from the previous study using the variety Gannoruwa selection, and seedlings and air layered plants of the same variety were used. The experiment was established in a RCBD with eight

EFFECT OF ROOTSTOCKS ON ROOT KNOT NEMATODE AND YIELD OF GUAVA 47 replicates. Plants were established in 4 m x 4 m spacing and maintained using recommended cultural practices of the DOA. Data on growth and yield characters were recorded in six months interval. The third trial was established at the ARS, Kalpitiya to test the susceptibility of different planting materials for root knot nematodes. A site previously affected by root knot nematode infestation to guava was selected to the study. Seedlings and grafted plants of guava to the root stock of P. guajava and P.friedrichstalianium were planted in RCBD with three replicates. Data were analyzed using MSTAT statistical package in all studies. Confirmation of resistance of Psidium spp. was done by artificial inoculation of root knot nematodes at the Fruit Research and Development Institute at Horana, Sri Lanka. Nematode reproduction factor (RF) was used to verify resistance in P. friedrichstalianium .

Results showed that rootstock species, grafting method, and the interaction effect between rootstock species and grafting method were statistically significant (p<0.05; Table 1). Psidium cattleianum was grafting-incompatible with all P. guajavavarieties tested. Higher percentage success was observed when all varieties of guava were cleft grafted to P. friedrichstalianium . However, patch budding was not successful with this rootstock. Both grafting and budding showed a success rate of about 80% whenP. guajava was used as the rootstock. Compatibility of P. friedrichstalianium were previously reported by Bogantes-Arias and Eric (2010) and Regina et al. (2012). Renata et al. (2015) showed that some accessions of P. cattleianum were grafting-compatible with guava at lower percentage, however, those were died after field planting. In the present study, P. cattleianum was incompatible even at grafting stage. All varieties tested behaved similarly in grafting with different rootstock spp. Growth of scion shoots at 8 weeks after grafting showed that all grafted/budded plants have grown similarly.

Height of seedlings at initial stage was greater compared to that of grafted and air layered plants when different planting materials of guava were grown. Height of the guava/guava plant was higher than that of P. friedrichstalianium/guava plants. Incompatible reactions were not observed between the two species after field planting of these plants, however, rootstock and the scion wood plants were easily distinguishable by the colour of the stem. One year after planting, the height difference was not significant

48 EDIRIMANNA et al.

(p>0.05) in grafted and air layered plants. The highest stem height was observed in seedlings.

Table 1: Effect of root species, grafting method and scion wood variety on percentage grafting success and growth of shoot. Root stock spp. Grafting Scion wood Percentage Shoot length 8 method variety success of weeks after rafting/budding* grafting/ budding (cm) P. guajava Cleft Bangkok Giant 84 (68.5) ab 22.1 ab P. guajava Patch Bangkok Giant 80 (63.7) 18.6 P. guajava Cleft HoranaRosi 82 (65.0) ab 23.4 P. guajava Patch HoranaRosi 78 (62.4) b 19.8 P. guajava Cleft 86 (70.2) a Gannoruwa 22.6 Selection ab P. guajava Patch Gannoruwa 80 (63.7) 23.3 Selection P. friedrichstalianium Cleft Bangkok Giant 80 (63.7) ab 20.1 P. friedrichstalianium Patch Bangkok Giant 00 (0.99) c - P. friedrichstalianium Cleft HoranaRosi 78 (62.4) b 18.6 P. friedrichstalianium Patch HoranaRosi 00 (0.99) c - P. friedrichstalianium Cleft 82 (65.0) ab Gannoruwa 20.6 Selection c P. friedrichstalianium Patch Gannoruwa 00 (0.99) - Selection P. cattleianum Cleft Bangkok Giant 00 (0.99) c - P. cattleianum Patch Bangkok Giant 00 (0.99) c - P. cattleianum Cleft HoranaRosi 00 (0.99) c - P. cattleianum Patch HoranaRosi 00 (0.99) c - c P. cattleianum Cleft Gannoruwa 00 (0.99) - Selection c P. cattleianum Patch Gannoruwa 00 (0.99) - Selection CV % 11.3 13.8 Species. ** ns Grafting method ** ns Variety ns ns Species x grafting ** ns method Species x variety ns ns Grafting method x ns ns variety Species x grafting ns ns Method x variety *Values within parenthesis are arcsine transformed values. Arc sine values were used for statistical analysis; **Within a column, means followed by same letter are not significantly different at p=0.05; ns = non-significant.

Branching ability was the highest in air layered plants and its spread was higher compared to other types. Results indicated that growth of both types of grafted plants were similar at 12 months after planting. Air layered and grafted plants flowered 245-260 days after planting, however, seedlings took about 320 days. Number of fruits per plant was not significantly different (p>0.05) among the treatments. Fruit size, shape, appearance and the total soluble solids (TSS) were the same in air layered and grafted plants. Little variation of fruit size shape and appearance and quality characters were

EFFECT OF ROOTSTOCKS ON ROOT KNOT NEMATODE AND YIELD OF GUAVA 49 observed among seedlings.

The symptoms of root knot nematode infection appeared 6 months after planting in seedlings of guava and when it was used as rootstocks at ARS, Kalpitiya. Seedlings and rootstock of guava died at 8 months after planting. However, no symptoms or gall formation was observed in seedlings of P. friedrichstalianium and when it was used as a rootstock and these were successfully grown. The RF value for the species was zero thus confirming its resistance.

Results confirmed the suitability of P. friedrichstalianium as a rootstock for the production of root knot nematode-resistant planting material of guava.

REFERENCES

Bogantes-Arias, A. And E. Mora-Newcomer. 2010. Evaluation of four rootstocks for graft in guava (Psidium guajava L.). Mesoamericana 21(1): 103-111.

Freitas, V.M., Correa, V.R., Motta, F.C., Gomes, M.M.,Careneiro, M.D.G., Silva, D.B., Mattos, J.K., Nicole, M., and Carneiro. R.M.D.G.2014. Resistant accessions of wild Psidium spp. To Meloidogyne enterolobii and histological characterization of resistance Plant Pathology 63(4): 738-746.

Rajapakse, R.V.D.U.P., Hettiarachchi, C. and Dassanayake, R.S. 2015. Molecular identification of root knot nematodes (Meloidogyne species) in Sri Lanka. Proceedings of the 71st Annual Sessions. Sri Lanka Association for the Advancement of Science.

Regina, M.D., Gomes, C.A., Vania, M. deF., and Cesar, B.G. 2012. Major guava nematode: genetic control perspectives. 3 rd international symposium of Guava and Other Myrtaceae April 23-25, 2012, Petrolina,PE, Brazil

Renata, R.R., GraziellaS.C., Claudia S.M., Ricardo M.S., and CintiaA.B. 2015. Grafting guava on cattley guava resistant to Meloidogyne enterolobii. CienciaRural (on line version) 45: 9.

Taylor, A.L. and J.N. Sasser. 1978. Biology, Identification and Control of Root-Knot Nematodes (Meloidogyne spp.). N.C. State Univ. Dept. Plant Path., and USAID, Raleigh, N.C. 111. GENETIC VARIABILITY, PHENOTYPIC AND GENOTYPIC CORRELATION AND PATH COEFFICIENT ANALYSIS OF BLACK GRAM ( VIGNA MUNGO (L) HAPPER)

M.J.M.P. KUMARARTHANA, AT. SOORIYARARCHCHI AND R.R.P.S. ARIYAWANSHA

Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka

EXTENDED ABSTRACT

In Sri Lanka, black gram is a popular legume crop as it is suitable for unfertile marginal lands in the dry and intermediate zones. Annual production and extent of black gram in 2014 was around 9,657 mt and 11,226 ha, respectively but the average productivity is around 0.83 t/ha, which is very low compared to other black gram

Annals of Sri Lanka Department of Agriculture 2016. 18: 50 - 45 growing countries (Agstat, 2014). Therefore, it is important to improve the adaptability over diverse environments and potential yield of black gram. For yield improvement, it is essential to start an efficient breeding programme. Genetic diversity is one of the criteria of parent selection in a hybridization programme. The coefficient of correlation between yield and its contributing traits show a complex relationship. Path coefficient analysis partitions the components of correlation coefficient into direct and indirect effects and visualizes the relationship in a more meaningful way. Therefore, the present study was conducted to study the effects of different yield components on seed yield using parameters which indicate the relative importance of different traits, like variability, heritability, genetic advance, correlation and path coefficient.

Forty black gram germplasm lines were sown at the Field Crops Research & Development Institute, Mahailluppallama in a randomized complete block design (RCBD) with two replicates. Data of ten morphological characters, days to 50% flowering (FF), days to maturity (DM), number main branches (MB), plant height (PH), number of clusters per plant (CP), number of pod per plant (PP), number of seed per pod (SP), pod length (PL), yhousand seed weight (SW) and plot yield (Y) were recorded. Analysis of variance (ANOVA) was used to statistically analyse the data of each trait. F- test followed by least significant difference (LSD) test was applied for mean separation. : The genetic (c^), phenotypic (ffp) and environmental variance (er 0 ) for each traits were estimated (Johnson et al, 1955). Broad sense heritability (h^ B ) was estimated by the formula suggested by Johnson et al. (1955) and Hanson et al. (1956). Phenotypic (PCV), genotypic coefficient of variation (GCV), genetic advance (GA) and coefficient of variability (CV) were calculated by the formula suggested by Johnson et al, (1955) .The genotypic (r^) and phenotypic (r p) correlation coefficient was used to calculate all

GENOTYPIC CORRELATION AND PATH ANALYSIS OF BLACK GRAM 51 possible combinations (Miller et al, 1958; Hanson et al, 1956; Johnson et al., 1955). Correlation coefficients were further partitioned in to components of direct and indirect effect by path coefficient analysis originally developed by Wright (1921).

The mean sums of squares due to genotype were highly significant at 1% level for all tested characters. This shows the existence of high variability for all tested traits in the blackgram germplasm. The highest value (>20%) of GCV were estimated for plant height (33.16), number of pods per plant (27.29), number of main branches (25.37), and grain yield (23.58). whereas higher PCV values (>25%) were recorded for plant height (35.12), grain yield (34.07), number of pods per plants (32.13) and number of main branches (25.37). Higher value of GCV for plant height, number of pods per plants, grain yield, and number of main branches indicate better chance for selection for these traits to be successful. Higher values of broad sense heritability ( kt,„) (>70%) were recorded for days to 50% flowering (98.99), 1000 seed weight (89.4), plant height (89.13), days to maturity (72.8) and number of pods per plant (72.1).

Expected genetic advance at 5% selection intensity expressed as percentage of population mean, ranged from 7.63% of pod length to 63.51% for plant height. Days to 50% flowering shows significant positive correlations with, plant height and number of seeds per plant. Days to maturity represented significant positive correlation with grain yield and plant height. Number of main branches per plant showed significant phenotypic and genotypic correlation with, number of clusters per plant and plant height. Plant height showed significant positive correlation with days to 50% flowering and days to maturity. Number of cluster of plant exhibit highly significant positive phenotypic and genotypic association with number of main branches, number of seeds per pod and pod length. Number of pods per plant was found to show significant positive correlations of both genotypic and phenotypic associations with plant height, seeds per pod, pod length and grain yield. Number of seeds per pod was showed significant positive relationships with days to 50% flowering, plant height number of clusters per plant, number of pods plant and pod length as both genotypic and phenotypic correlations. Pod length showed significant positive correlation with number of clusters per plant, 1000 seed weight and number of pods per plant.

The significant positive association in both genotypic and phenotypic of 1000 seed weight was found only with pod length. Number of main branches, plant height and pod length were significantly and positively associated with grain yield at both genotypic and phenotypic level. In order to find out source effect relationship between yield and its related characters, path analysis was taken up in the present investigation. Number of

52 KUMARARATHNA et al. main branches had the highest positive direct effect followed by Plant height (0.190), number of pods per plant (0.162) and 1000 seed weight (0.109) (Mehra et al., 2016).

According to this study there was a significant genetic variability among genotypes of black gram for all traits. Plant height, number of pods per plant and number of main branches showed high heritability along with high genetic advance. Number of main branches, plant height, and number of pods per plant and pod length had highly significant and positive correlations with seed yield and also among themselves. Number of branches followed by plant height, pods per plant and pod length showed highest direct effect on the grain yield. Hence, direct selection of these traits would be worthwhile.

REFERENCE

AgStat, 2014. Socio -Economic and Planning Centre, Department of Agriculture, Peradeniya, Sri Lanka. XI. 22-24. Hanson, C.H., H.F. Robinson and R.E. Comstok. 1956. the biometrical studies on yield in segregating population of Korean lespedeza. Agronomy Journal, 48:268-272. Johnson, H.F., H.F. Robinson and R.E. Comstock (1955). Estimation of genetic and environmental variability in soybean. Agron Journal, 47:314-318. Mehra, R., A.T. Tikle, A.Suxena, A. Munjal, Rekhakhandia and M. Singh 2016. Correlation, path- coefficient and genetic diversity in black gram (Vigna mungo (L.) Hepper). International Research Journal of Plant Science 7(1): 01-011. Miller, P.A., Willianis, H.F. Roginson and R.E. Comstock. 1958. Estimates of genotypic and phenotypic and environmental variance and covariance and their implication in section. Agron Journal 50:126-131. Wright, S. 1921. Correlation and causation. Journal of Agriculture Research 20:557-587.

Annals of Sri Lanka Department of Agriculture 2016. 18: 53 - 45

ASSESSMENT OF THE TEMPERATURE REGIME IN AGRO ECOLOGICAL REGIONS OF SRI LANKA

A.B. A BEYSEKERA 1, B.V.R. P UNYAWARDENA 1, A.K. H ETTIARACHCHI 1, 1 2 E.V.G.N. J AYARATHNA BANDA AND K.H.M.S. P REMALAL

1 Natural Resources Management Centre, Peradeniya, Sri Lanka 2 Department of Meteorology, Colombo, Sri Lanka

EXTENDED ABSTRACT

Despite the relatively small aerial extent, Sri Lanka demonstrates a variety of climatic conditions depending on the geographical settings of respective locations. The climate of Sri Lanka is considered as tropical monsoonal with a marked seasonal variation of rainfall. The spatial variation of temperature regime in the island occurs mainly due to altitude. With increasing altitude, the atmospheric temperature decreases and this phenomenon is known as the Atmospheric Lapse Rate. In addition, the mean monthly temperatures differ slightly depending on the seasonal movement of the sun, with some modifying influence caused by rainfall. In the lowlands, the mean annual temperature is 27.5 °C and the mean daily range is 6 °C. In the Central highland with altitudes up to 2,400 m a cooler climate is experienced. At Nuwara Eliya, altitude 1,800 m, the mean annual temperature is 15.9 °C and the mean daily temperature range varies 5-10°C (National Atlas, 2007). The coldest month with respect to mean monthly temperature is January and the warmest months are April and August.

The delineation of 46 Agro-ecological region (AER) boundaries of Sri Lanka has been based on the monthly rainfall regime at 75% probability level, terrain characteristics, predominant soil type, land use and vegetation (Punyawardena, 2007). Elevation differences have been taken in to the account to capture the spatial variation of temperature as a proxy parameter. However, the temperature regime among different AERs of the country have not quantified yet. It has limited the use of the AER map especially in recommending crops for each AER where temperature regime should also be taken in to account.

Therefore, this study was undertaken to assess the temperature regime of all 46 AERs using available minimum and maximum temperature data and by means of GIS technique, so that agricultural and other weather related decisions and research can be accomplished without limitations in future. Daily maximum and minimum temperature data were collected from 38 meteorological observation stations for 30 years from 1986-2015. Then monthly average maximum temperature and monthly average minimum temperature values were

54 ABEYSEKERA et al. calculated. Thirty year averages were computed for resulted maximum temperature and minimum temperature values for 23 AERs with the available temperature data. To find temperature values for rest of the AERs, a surface interpolation method known as Krigging was selected using Arc-GIS (version 9.2) software.

Geographic locations of the meteorological stations considered for the study were geo-referenced to the geographical coordinate system and temperature values were linked. The location map was overlaid on the Agro-ecological Region map of Sri Lanka (Punyawardena et al., 2003). Then, the values for remaining AERs were calculated. Sita Eliya, Kurunegala and Mahailluppallama representing Wet, Intermediate and Dry zones, respectively, were considered as a sub-set of total data set to validate the interpolation or estimation method of GIS software.

There is an apparent increasing trend of all temperature parameters from Wet zone to Dry zones while decreasing trend with increasing altitude as expected. However, there was hardly any discernible trend in temperature parameters with respect to expect quantum of rainfall in each AER confirming that it is only a function of altitude, movement of the sun and climatic zone.

During First Inter-Monsoon (FIM), in all AERs, the highest values are recorded in the month of April due to sun’s overhead position. May to September, the period of South West Monsoon (SWM), the highest maximum values are recorded in AERs of the Dry zone due to adiabatic warming of south west monsoonal wind stream after crossing the Central highlands while blowing over the Dry zone. In Second Inter-Monsoon (SIM) period, when the island receives considerable amount of well distributed rainfall, the maximum temperature values increases from Wet Zone to Dry Zone following to the altitude. Compared to the other rainfall seasons, in the North East Monsoon (NEM) season, the maximum temperature values of the Intermediate and Dry zones are slightly less. This is mainly attributed to the thick cloud cover of NEM over these regions which cut-off high solar irradiance and northerly and north-easterly wind blowing from High pressure area of the northern Indian land mass which is cool and dry.

However, lowest minimum temperature values of all AERs of the Dry zone are recorded during the month of January, a common phenomenon to experience across all

TEMPERATURE REGIME IN AGRO ECOLOGICAL REGIONS OF SRI LANKA 55

AERs of the country due to moisture bereft and cold north east monsoonal wind coming from cold northern Asian land mass and enhanced radiation cooling at night in the absence of clouds. The DL 4 agro-ecological region depicts comparatively higher minimum temperature values throughout the year compared to the other AERs.

Although these interpolated values can be used for the agriculture and weather related decision making in different AERs without wide margin of errors where there are no observed climatic data available, it is very important to establish new meteorological stations in those regions to capture the actual picture of thermal regime.

Temperature is a very important climatic parameter which directly influences agriculture and weather related decision making. Although there were some temperature assessments done on district basis or meteorological stations basis, temperature values assigned for AER will be more useful in agriculture and weather related decision making and research purposes with considerable amount of high accuracy.

REFERENCES

Punyawardena, B.V.R. 2007. Agro Ecology. In the National Atlas of Sri Lanka. pp. 98-100. 2 nd edition. Survey Department of Sri Lanka, Sri Lanka.

Punyawardena, B.V.R., T.M.J. Bandara, M.A.K. Munasinghe, N. Jayaratna Banda, 2003. Agro Ecological Regions of Sri Lanka (Map), Department of Agriculture, Sri Lanka.

Survey Department. 2007. The National Atlas of Sri Lanka, 2007. 2 nd edition, Survey Department, Sri Lanka. 36-56 pp.

Annals of Sri Lanka Department ofAgriculture 2016. 18: 56 - 57

MICRO PROPAGATION OF NEW ANTHURIUM VARIETIES: LANKA BEAUTY & LANKA KUMARI

R.N.I. PERERA 1, R.G.A.S. RAJAPAKSHA 2, W.M.E.K. BANDARANAYAKE 2 AND D A. SAMARASINGHA 2

1 Fruit Research & Development institute, Kananwila, Horana, Sri Lanka 2 Horticultural Crops Research & Development Institute, Peradeniya, Sri Lanka.

EXTENDED ABSTRACT

Anthurium is one of the tropical cut-flower that has a high demand in the international market. In the global market, among tropical cut-flowers traded values of Orchids and Anthuriums have first and second places, respectively. Anthuriums are traditionally propagated by seeds. Propagation through seeds is not an effective method because the progenies may be heterozygous due to cross pollination and low seed viability. Application of tissue culture techniques is the best alternative for commercial scale planting material production of Anthurium. Therefore, this study was focused to develop rapid propagation technique for two newly developed Anthurium varieties (Lanka Kumari & Lanka Beauty ).

As explants, immature tender leaf pieces from one year old mother plants were used and following surface sterilization 1 cm 2 leaf pieces were established for callus induction. Callus induction time and rate were observed with two different Callus induction media for both varieties under dark conditions at 27 oC for 2-3 months. Callus were transferred to regenerate in the media consisted of MS salts with NH 4NO 3 lowered to 250 mg/l, 30 g/l Sucrose, 7 g/l Agar and BAP ranges from 0.2-1 mg/l. Callus age was considered when transferring to regenerate. They were at 11/2, 2, 21/2 and 3 months from the explants establishment. Shoot multiplication was carried out in MS media with three different BAP concentrations (0.5 mg/l, 0.8 mg/l and 1 mg/l) for both varieties. Average shoot multiplication rate was recorded in six sub-culture cycles in each treatment. After that multiplied shoots were transferred to rooting medium to make complete plantlets.

Both media tested, produced callus after one month from the initiation. The medium B (MS salts+1 mg/l BAP+0.1 mg/l 2,4,D) produced large whitish callus while the medium A (MS salts+0.25 mg/l BAP+0.2 mg/l IAA) produced small calluses along the margins of the leaf cuttings. Results showed the both media were able to produced callus equally. Only 21/2 months old calluses were regenerated. BAP concentration in the media significantly affected shoot regeneration and there was no varietal effect or interaction. The media consisting of 0.2 mg/l BAP, showed a better response in

MICRO PROPAGATION OF ANTHURIUM VARIETIES 57 regeneration for both varieties. The medium with 1 mg/l BAP showed highest shoot multiplication rate of 16.3 and 11.2 in varieties Lanka Beauty and Lanka Kumari, respectively. Results showed that an increasing trend of shoot multiplication in higher concentrations of BAP. Rooting observed in the MS medium with 1 mg/l IBA and 1% activated charcoal for both varieties. In conclusion, this study was able to introduce rapid propagation protocol for two Anthurium varieties “Lanka Kumari” & “Lanka Beauty”.

REFERENCE

Chen, F.C., Kuehnle, A.R. and Sugii, N. Anthurium roots for micropropagation and Agrobacterium tumefaciens-mediated gene transfer. Plant Cell Tissue and Organ Culture, 49 (1). Chen, J., D.B. McConnell, R.J., Henny and Everitt, K.C. 2003.Cultural guidelines for commercial production of interiorspace anthurium. University of Florida, IFAS extension, EHN956. Cimen, A. and Ozge, C. 2009. Micropropagation of Anthurium andreanum from leaf explants. Pakistan Journal of Botany 41 (3): 1155-1161. Farsi.M., Taghavizadeh Yazdi ME. and Qasemiomran, V. (2012).African Journal of Biotechnology Vol. 11(68), pp. 13162-13166, 23 August, 2012.ISSN 1684-5315 ©2012 Academic Journals. George, E.F., M.A. Hall and J.D. Klerk. 2008. Plant propagation by tissue culture, Volume 1. The Background, Springer, pp. 65-75. Islam, S.A., Dewan, M.M.R., Mukul, M.H.R., Hossen, M.A., Khatun, F. 2010. In vitro regeneration of Anthurium andreanum cv. NITTA. Bangladesh J. Agril. Res. 35(2) : 217226. Murashige, T. and Skoog, F.1962. A revised medium for rapid growth and bio-assays with tobacco tissue cultures. Physiologica Plantarum 15 473-497. Poddar, K., R.K. Vishnoi and S.L. Kothari. 1997. Plant regeneration from embriyogenic callus of finger millet Eleusine coracana (L.) Gaertn., on higher concentrations of NH4NO3 as a replacement of NAA in the medium. Plant Science, 129: 101-106. Silva, J.A.T., S, Nagae and M,Tanaka., 2005. Effect of Physical Factors on Micropropagation of Anthurium andraeanum . Plant Tissue Culture, 15(1): 1-6. Thomas, G., 1986. Factors affecting plant regeneration from leaf segments of Anthurium scherzerianum Schott (Araceae) cultured in vitro. Plant Cell, Tissue and Organ Culture, 6 (2): 115-125.

Annals of Sri Lanka Department of Agriculture 2016. 18: 58 - 45

PERFORMANCES OF DIFFERENT BREEDING METHODS BASED ON THE ESTIMATED GENETIC PARAMETERS IN F4, F5 AND F6 GENERATION ADVANCEMENTS OF COWPEA (VIGNA UNGUICULATA (L). WALP)

M.C. M ILLAWITHANACHCHI 1, V. A. S UMANASINGHE 2, A.P. B ENTOTA 1 1 1 B.N. S AMARANAYAKE AND N.T. P RATHAPASINGHE

1Grain Legumes & Oil Crops Research & Development Center, Angunakolapellassa, Sri Lanka 2Faculty of Agriculture, University of Peradeniya, Sri Lanka

INTRODUCTION

Knowledge about the relative efficiency of different breeding methods may greatly help plant breeders in selecting a better method to be adopted in a particular crop (Adnan et al., 2011). In cowpea cultivation of Sri Lanka there are farmer grown cultivars with some good attributes such as drought tolerance, better taste, elasticity of growth pattern according to the rainfall changes, yet the yield performances were at poor level. So there is a demand for high yielding cowpea varieties with better adaptability. (Millawithanachchi et al., 2012).

Hence, an efficient breeding method to develop adaptable cowpea varieties for the farmer field conditions is required. Therefore, this study was conducted with the objectives of comparing three breeding methods at F4, F5 and F6 generations based on the mean performance and genetic parameters and other selected traits using two cross combinations of cowpea.

F3, F4, F5 and F6 generations were advanced with a series of trials following pedigree method (PM), modified bulk method (MB) and Single Seed Descent (SSD) method using two cross combinations of four distinct parents of cowpea, CP19 X Waruni (cross 01) and CP20 X CP22 (cross 02) at the Grain Legumes and Oil Crops Research and Development Centre (GLORDC) at Angunakolapellessa, Sri Lanka starting from 2011 yala. From F2 to F5 in PM 100 progeny lines were derived from respective previous population following within and between line selections. SSD method followed for the two populations from F2 to F4 and F5 generations were established as the progeny lines in both crosses. In modified bulk method (MB) F3 and F4 bulk populations were established with the bulked seed samples from superior 5% of selected plants of the F2 and F3 respectively. Hundred plants were established as lines in the F5 generation selected from F4. Ten best lines of each F5 generation of three breeding methods belong

PERFORMANCES OF BREEDING METHODS BASED ON COWPEA 59 to two crosses were selected based on the visual selections by breeders and farmers. The ten best lines selected from each of the three breeding methods along with the parents of the relevant crosses and three standard checks were evaluated for their performance. Two separate experiments were conducted for the two crosses. Each experiment was laid out in a RCBD with three replicates, at GLORDC.

Data were recorded on plant height at maturity, number of peduncles per plant, number of pods per plant, number of seeds per pod, average length of pod, hundred seed weight and yield per plant in F4, F5 and F6 generations. Phenotypic (Vp) and Genotypic (Vg) variances and the Genotypic (GCv) and phenotypic (PCv) coefficients of variation, heritability broad sense (Hb) and genetic advance (GA) were estimated separately for each selection method per each cross at F4, F5 and F6 populations.

Results indicated that for the plant height character SSD populations have retained more genetic variability in F4 and F5 compared to those developed by other two methods due to less selection pressure on the SSD population than the pedigree and MB method populations. In F6 PCv and GCv were reduced in SSD compared to the other two methods due to the selection pressure at F5 generation. High level of GCv and PCv of plant height indicated that it is highly variable character. Though it has recorded high Hb, due to low to moderate nature of GA fixable additive gene effects are low for this character. The results with higher GCv, PCv Hb and GA at early generations indicate considerable proportion of additive or additive x additive gene effects exist for pods per plant character and additive effects of this character can be fixed by early selection. According to Kurer, 2007, pods per plant is the major component of seed yield among many components. This trait can be improved by simple selection. SSD method recorded the highest variability for pod length character with higher GCv, PCv and Hb and other two methods recorded moderate to low GCv, PCv and high Hb in early generations. Seeds per pod, GCv, PCv and Hb were high to moderated for all the methods in F4. At F6 level SSD method recorded low GCv and moderate PCv. MB and pedigree methods recorded moderate GCv while Hb was high for pedigree and SSD methods.

PCv and GCv of seed weight were moderate for all the methods and high Hbs were recorded by all the methods at F4. All the methods recorded low GA values. SSD has recorded the highest values for GCv, PCv and Hb with higher GA as % of mean for yield per plant while pedigree and MB methods recorded moderate values for GCv and PCv and higher values for PCv in F4 and similar pattern for SSD in F5. The other two methods recorded low GCv and high PCv along with low GA. For the yield per ha character SSD was the highest variability recorder for GCv, PCv in F6 for both crosses.

60 MILLAWITHANACHCHI et al.

According to genetic parameters of the 3 methods the highest variation was observed with SSD method due to low selection pressure incurred compared to that in the other two methods at F2, F3 and F4 levels. At F6 level evaluations with equal number of lines per method at same trial, SSD selected lines performed as well as those from other two methods and resulted in better GA values than with the other two methods. Therefore, SSD can be identified as a better method with low cost compared to the other two methods tested.

Highest variation was observed with SSD method in F4 and F5 generations due to low selection pressure exerted on SSD populations. SSD selected lines also performed well and resulted in better GA values in comparisons to other two methods at F6 generation. Since the SSD method has not reduced the GA up to F6 level, SSD can be identified as a better method with low cost compared to the other pedigree and modified bulk methods to advance cowpea populations without losing genetic variability at early generations.

REFERENCES

Adnan Kanbar, Katsuhiko Kondo and H.E. Shashidhar. 2011. Comparative efficiency of pedigree, modified bulk and single seed descent breeding methods of selection for developing high- yielding lines in rice (Oryza sativa L.) under aerobic condition. Electronic Journal of Plant Breeding, 2(2): 184-193. Kurer, S. 2007. Genetic Variability Studies in F2 and F3 generations of cowpea. (Vigna unguiculata (L.) Walp). MSc. Thesis. Department of genetics and Pant Breeding. University of Agricultural Sciences, Dharwad. Millawithanachchi, M.C., Bentota, A.P., Weerasinghe,P. Saranasinghe, S.N.K. Prathapasinghe, N.T. and. Kumri, R.A.C. (2012). Cultivation of Rainfed cowpea [Vigna unguiculata (L). Walp] in the Monaragala district of Sri Lanka: status, constraints and breeding requirements. Annals of the Sri Lanka Department of Agriculture. Vol. 14.

Annals of Sri Lanka Department of Agriculture 2016. 18: 61 - 45

SOIL MOISTURE DEPLETION AND ITS INFLUENCE ON RAISING SPIKLET TEMPERATURE AND POLLEN FERTILITY IN DIFFERENT RICE VARIETIES

L.C. SILVA M.S. NIJAMUDEEN 2, H.G.P.B. DHARSHANA 1 W.M.W. WEERAKOON 1 AND P. MAHINDAPALA 1

1 Field Crop Research & Development Institute, Mahailluppallama, Sri Lanka 2 Regional Agricultural Research Station, Aralaganwila, Sri Lanka

EXTENDED ABSTRACT

Prominent dry period may occur from May to September and variability of annual rainfall of dry zone was higher in yala (Premalal, 2009). Further, maximum air temperature increased more than 36 °C in late season flowering. If synchronize flowering of rice with critical temperature, pollen sterility may occurred with high RH (Weerakoon et al, 2008, 2009). Due to climate change, vulnerability of temperature and moisture stress will be higher in dry zone rice farming in future. Therefore, rice varieties were screened to (i) study the pollen fertility variations and related parameters among the varieties with soil moisture depletions and temperature stress and (ii) select the most sustainable varieties for future climate changes.

Field experiment was conducted in Field Crop Research and Development Institute, Mahailluppallama during 2015 yala season. Nine rice varieties or promising lines (Agt14, Agt17, Bg250, Bg12-1666, Bg300, At308, At303, Bg10-2881 and Bg12- 1365) were screened with nearly saturated, field capacity, 25% allowable depletion and 50% allowable depletion. Design was two factor factorial split plot design with three replicates. However, to maintain particular depletion level main plots were separated by two meter width free area and all bunds were covered with 700 gauges polythene to minimize leaching of water to next main plot. Rice varieties were direct seeded on the well prepared sub plots on 11 th June 2015. Weed control, fertilizer management pest and diseases management was done according to Department of Agriculture recommendations. Depletion levels were imposed from 42 Days After Sowing (DAS) to dough stage of the crop based on soil moisture depletion curve of the experimental site. Volumetric moisture content and above ground bio mass were recorded at late booting stage of the crop. Pollen fertility was recorded at maximum stress using potassium iodide staining method (Smith et al., 2001). Flag leaf and spikelet surface temperature were recorded using Infrared thermometer (Extech ®-China-50 to 650 oC). Leaf temperature difference (ALT) was calculated at the date of maximum moisture stress. Plot yield was converted into tons/ha. Analysis of variance and mean separation was done. Further, VMC and average value of 9 varieties of ALT in different days were correlated.

62 SILVA et al.

Soil moisture depletion from panicle initiation to heading restricted the plant growth in 25 % and 50 % depletion levels significantly compared to saturate and field capacity. Because of that, saturated and field capacity provides the adequate soil moisture for plant growth. Interaction of soil moisture depletion and varieties on biomass production was not significantly different. Therefore, main effect of bio mass production was considered and higher biomass production was recorded in At308, Bg13-1265 and Bg300 in all depletion levels.

Leaf surface temperature is a physiological and transpiration related measurements (Belco et al., 2013). Leaf temperature increased with soil moisture depletion without varietal differences. But leaf temperature difference (ALT) would become lower with increasing soil moisture depletion. In lower ALT, the stomata in the leaves would be closed and increased the vapour pressure deficit and canopy cooling ability would decrease. Therefore, some heat stress could be generating within the canopy and emit more infra red waves, the ultimate result was increase of leaf temperature. Spikelet surface temperature was significantly increased with increasing moisture stress compared to saturated condition due to decrease of canopy cooling. There was no significantly difference in spikelet surface temperature between field capacity and 25 % soil moisture depletion. At 308, Bg300 recorded the comparatively lower spikelet surface temperature up to 25 % depletion. Further, Bg13-1265 and Bg10-2881 increased the spikelet surface temperature up to 31.2 and 32.4 oC at 50 % soil moisture depletion. Result revealed that, those varieties may be maintained canopy cooling up to 25 % soil moisture depletion (lesser than critical temperature). If high temperature synchronizes with maximum moisture stress, spikelet surface temperature would be further increase by cumulative effect with genotypic variations.

Pollen fertility % was highest in saturated and field capacity condition. With increasing soil moisture depletion, Bg300 recorded highest pollen fertility % at 25 % and 50 % depletion levels. Pollen fertility of Agt17 was perform well in favorable moisture conditions but rapidly decreased the fertility at moisture stress. Bg13-1265 slowly decreased the pollen fertility with increasing soil moisture depletion. variety At308 decreased the pollen fertility from 87.6 to 70.5 % from saturated to 25 % soil moisture depletion.

INFLUENCE OF SOIL MOISTURE DEPLETION ON POLLEN FERTILITY IN RICE 63

Rice yield was significantly decreased with increasing soil moisture depletion. The highest average yield was recorded in saturated condition and the lowest average yield was recorded in 50 % depletion. Yield of At303, Bg13-1265, At308, Bg300 and Agt17 comparable with Bg10-2881.

Result concluded that, biomass production, pollen fertility %, leaf temperature difference (ALT) were affected by soil moisture depletion at reproductive stage of rice. Further, spikelet surface temperature increased with increasing soil moisture depletion. Leaf temperature difference could be the better indicator for measuring crop response with soil moisture depletion. With considering biomass production, pollen fertility and spikelet surface temperature at 50 % soil moisture depletion, variety Bg300 would be tolerant for moisture stress and Bg13-1265, At308 would be moderately tolerant. Therefore, Bg300 was the most sustainable and Bg13-1265 and At308 was moderate among the tested varieties in late season moisture stress in future environment.

REFERENCES

Belco, N., M. Zaman-Allah, N.N. Diop, G. Zombrge, J.D. Ehlers and V. Vadez. 2013. Restriction of transpiration rate under high vapour pressure deficit and non limiting water condition is important for terminal drought tolerance in cow pea. Plant Biolgy 15 (2): 304-16. Premalal, K.H.M.S. 2009, Climate Change in Sri Lanka, Proceedings of the 1 st National Conference on Climate Change & Its Impacts on Agriculture, Forestry andWater,10-11 Sept. 2009, Kandy, Sri Lanka, Eds. M.M.M. Aheeyar. Sri Lanka Water Partnership & Global Water Partnership -South Asia Colombo. August 2012. Smith, M.B., H.T. Horner and R.G. Palimer. 2001. Temperature and photoperiod effect on sterility in cytoplasmic male-sterile soybean. Crop Sci. 41: 702-704. Weerakoon, W.M.W., A. Maruyama and K. Ohba. 2008. Impact of humidity on temperature induced grain sterility in rice. Journal of Agronomy and Crop Science 194: 135-140. Weerakoon, W.M.W., T. Abeywickrama, W.A.J.M. De Costa and A. Maruyama. 2009. Outcrossing of heat stress affected spikelets of low land rice in the sub humid zone of Sri Lanka and its long term implications. WWW.niaes.affrc.go.jp./macro.

Annals of Sri Lanka Department of Agriculture 2016. 18: 64 - 49

NEED BASED NITORGENMANGEMTN OF MAIZE (ZEA MAYS L.) GROWN IN THE DRY ZONE OF SRI LANKA USING A SIX PANEL LEAF COLOUR CHART

K.A. RENUKA AND W.M.I. SENAVIRATHNA

Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka

EXTENDED ABSTRACT Maize is the second most important cereal crop grown in Sri Lanka. Local average maize yield recorded is 3.58 t/ha while the potential yield of the crop is 7 t/ha. Among various reasons accounting such low productivity, inefficient utilization of N can be considered as one of the most critical determinants of maize productivity. Farmers generally apply N fertilizer in fixed times as basal and top dressing (4 weeks after planting) without considering the real N requirement of the crop at different growth stages. Hence, such applications may be either excessive or not adequate to meet the crop N demand. The optimum use of N can be achieved by matching N supply with crop demand (Bijay Singh et al, 2002). Leaf greenness measured using chlorophyll meter is positively correlated with leaf chlorophyll content and leaf N content (Wood et al., 1993 and Inada, 1985). Leaf Colour Chart (LCC) devised based on chlorophyll meter readings can be considered as non-destructive techniques of determining plant N status (Ali et al., 2012). LCC has been tested on maize in India and USA for need based nitrogen management (Anthony Nguy et al., 2015). However, LCC has not been tested for N management of maize in Sri Lanka. Hence, this experiment was conducted to study the applicability of LCC to determine the need based N requirement of maize grown in Sri Lanka.

Two experiments were conducted at FCRDI, Mahailluppallama, Sri Lanka from

2013 Yala season to 2014 Yala season. Experimental site was located at DL Jb agro ecological region and Reddish Brown Earth soil is the predominant great soil group, Rhodustalfs (Panabokke, 1996). One experiment was conducted to determine optimum LCC values and the other to validate the use of those optimum LCC values in N management of Maize. Both experiments were repeated in Yala and Maha seasons during the study period and locally cultivated hybrid (Pacific-999) and open pollinated maize varieties (Badra and Ruwan) were used. Treatments for experiment of determination of optimum LCC values were, 75, 150, 225, 300 kg N /ha and experiment of validate the optimum LCC values were no nitrogen, 120 kg N/ ha in three equal splits, 150 kg N/ ha in three equal splits, 30 kg N/ha (basal) + need based - LCC < 4.5 (6 th leaf stage (V6) to before silking (R1) stage), 30 kg N/ha (basal) +need based - LCC < 5 (V6 to before R1 stage), 30 kg N/ha (basal) +Need based - LCC < 4.5 (V6 to before R1 stage) and LCC < 5 (at R1 stage), 30 kg N/ha (basal) +Need based - LCC <5 (V6 to before R1 stage) and LCC < 5.5 (at R1 stage).Treatment arranged in split plot design with four replicates. Both

NEED BASED NITORGEN MANGEMTN OF MAIZE USING LEAF C OLOUR CHART 65 experiment, all treatments received 45 kg/ha P 2O5 and 30 kg/ha K 2O as triple supper phosphate and muriate of potash as basal. All other agronomic practices were done as per the Department of Agriculture recommendations. Experiment of determination of optimum LCC values, nitrogen was applied in equal splits at 2 days before planting, knee height and at pre-tasseling stage. A six panel LCC, manufactured by the International Rice Research Institute was used in this study. LCC readings were taken from fully opened upper most leaves of 10 plants of each treatment at 7 days intervals from the 6 th leaf stage. Dry seed yield was recorded and relative grain yields were calculated. Cate and Nelson graphical method was modified to establish optimum LCC values (Cate and Nelson, 1987). In this method average LCC values at different growth stages were plotted against the relative grain yield for the corresponding treatments. Relative grain yield beyond which no significant yield increase was observed was selected as the horizontal critical level in the Cate and Nelson plot and the vertical critical level was selected to minimize outliers. Experiment of validate the optimum LCC values, in fixed time N management, N fertilizer was applied 2 days before planting, knee height and pre-tussling stage. Need-based N application was done based on the LCC values. From the 6 th leaf stage onward, LCC values were taken in weekly intervals. When the LCC value was less than the optimum value, 30kg N/ ha was applied. Seed yield and agronomic N use efficiency (AE N) were measured. Statistical analysis was performed using SAS. Duncan’s multiple range test for mean separation.

Results of the experiment for determination of optimum LCC values revealed that LCC values at vegetative and reproductive stages indicate the requirement of maintaining different optimum LCC values for the two growth stages. Hence Cate and Nelson graphical method was applied for vegetative and reproductive stages. Relative grain yield of 0.91 was taken as horizontal critical level because, beyond this value no significant yield increase was observed. Accordingly, LCC value of 4.5 could be selected as optimum LCC value for vegetative growth stage and 5 for reproductive growth stage.

In validation experiment, there was no interaction observed between varieties and N fertilizer management. There was no significant difference observed in seed yield among the need based application treatments (Table 1) despite the use of two slightly different LCC values of 4.5 and 5.0. Need based N fertilizer application of vegetative stage treatments; yield produced by the optimum LCC value of 4.5 was comparable to

66 RENUKA et al.

optimum LCC value of 5. there was no significant response to N fertilizer application at silking stage with different LCC optimum values (Table 1 )When compared to the similar amount of total N application, need based fertilizer application treatments

produced higher AE N than fixed time application (Table 2). LCC value 4.5 as optimum value for vegetative growth stage had the highest AENfor both seasons.

Table 1. Total N application and seed yield of different fertilizer application treatments. N treatment Total N Seed yield (t/ha )

application Maha Yala (kg/ha) 2013/14 2014 No Nitrogen 0 3.43 d 2.42 c 120kg N /ha in three equal split 120 5.37 c 6.18b 150kg N /ha in three equal split 150 6.26 b 6.76 a Need based - LCC <4.5 (V6 to before R1 stage) 120 7.48a 6.83 a Need based - LCC < 5 (V6 to before R1 stage ) 150 8.28 a 7.48 a Need based - LCC <4.5 (V6 to before R1 stage) and 120 7.40 a 6.73 a LCC < 5 (at R1 stage) Need based - LCC <5 (V6 to before R1 stage ) and LCC 150 8.22 a 7.23 a < 5.5 (at R1 stage) CV % 10.5 11.2 Note: In each column, means followed by the same letter are not significantly different at 5% probability level.

Table 2. Agronomic efficiency of different N management options for maize. Treatment Agronomic efficiency of N (kg/kg) Maha Yala 2014 Mean 2013/14

120kg N /ha in three equal split 16.1 b 31.3 b 23.7 150kg N /ha in three equal split 18.8 b 28.9 b 23.9 Need based - LCC < 4.5 (V6 to before R1 stage ) 33.8 a 36.8 a 35.3 Need based - LCC < 5 (V6 to before R1 stage ) 32.3 a 33.7 ab 33.0 Need based - LCC < 4.5 (V6 to before R1 stage ) 33.1 a 35.9 ab 34.5 LCC < 5 (at R1 stage) Need based - LCC <5 (V6 to before R1 stage ) LCC 31.9 a 30.9 b 31.4 < 5.5 (at R1 stage) Note: In each column, means followed by the same letter are not significantly different at 5% probability level.

LCC value of the fully opened mature maize leaf can be used to determine the N status of maize grown for both open pollinated and hybrid maize varieties irrespective of the cultivation season and the six panel LCC developed for rice can successfully be used for Maize. Maintaining a LCC value of 4.5 form vegetative to silking stage by adopting a need based N management strategy, agronomic efficiency of applied N can be increased by nearly 50% as the agronomic efficiency of N was increased from nearly 23 to 33.

NEED BASED NITORGEN MANGEMTN OF MAIZE USING LEAF COLOUR CHART 67 REFERENCES

Ali, M. M., Ahmed Al-Ani, Derek Eamus and K. Y. Daniel, Tan. 2012. Leaf nitrogen determination using handheld meters. Available at http://www.regional . org.au/au/asa /2012/precision-agriculture7979-alim.htm. Anthony Nguy, Robertson, Yi Peny, Timothy Arkebaure, David Scoby, James Schepers and Anatoly Gitelson. 2015. Using simple Leaf Colour Chart estimate leaf and canopy chlorophyll content in maize (Zea mays). Soil Science and Plant analysis, 46: 2734-2745. Bijay, Singh., S. Yadvinder, J. K. Ladha, K. F. Bronson and C. S. Khind. 2002. Chlorophyll meter and leafcolour chart based nitrogen management for rice and wheat in Northwestern India. Agronomy Journal, 94: 821-829. Cate, R.B. and L. A. Nelson, 1987. A simple statistical procedure for partitioning soil test correlation data into two classes. Soil Science Soc. Am. Proc. 35:658-660. Wood, C.W., D.W. Reeves and D.G. Himelrick. 1993. Relationship between chlorophyll meter readings and leaf chlorophyll concentration, nitrogen status and crop yield. Proceedings Agronomy Society of New Zealand 23:122-131.

Annals of Sri Lanka Department of Agriculture 2016. 18: 68 - 27

OCCUERENCE OF ANTHRACNOSE (COLLETOTRICHUM GLOEOSPORIOIDES PENZ.) AND RUST (GOPLANA DIOSCOREAE CUMMINS) DISEASES OF DIOSCOREA IN SRI LANKA

W.A.P.G. WEERARATNE, N.L.A.T.S. NANAYAKKARA, A.D. ANUSHIKA

AND D.D.D. DARMADASA

Horticulture Crops Research & Development Institutive, Peradeniya, Sri Lanka

EXTENDED ABSTRACT Yams (Dioscorea spp.) are one of the most diversified root crops which contain high nutrient value and medicinal properties with a potential in commercial cultivation. Out of the eight edible species existing in Sri Lanka, D. alata, D. esculenta, D. bulbifera, D. hispida, D. opposite, D. trifida and D. pentaphylla are present in natural ecosystems. D. rotundata was introduced from Africa. Two new improved D. alata varieties; Rajala, Kakulala and one D. esculenta variety Kukulala (Kadira) were released by the Department of Agriculture for cultivation in Sri Lanka in year 2007 (Thavabalachandran and Silva, 2013). Several diseases; fungi causing anthracnose, leaf spot, leaf blight, and tuber rot; and the yam mosaic virus (YMV) are known to infect Dioscorea throughout the World (Amusa et al, 2003). In Sri Lanka, various leaf spots and vine die-back have been reported in yam growing areas and research fields as well. However, very little is known about disease incidence, severity and yield losses. Anthracnose and other leaf spots can be controlled by certain fungicides. Currently, there is no fungicide recommendation for the management of diseases in yam cultivation in Sri Lanka and farmers also not adopted to practice any of possible control measures. Hence, cultivation of resistant varieties is the most effective and economical means to control in foliar diseases when they occurs frequently.

Studies were conducted at Horticultural Crops Research and Development Institute (HORDI) to identify causal organisms of major diseases, their field symptoms and resistance sources from local cultivars and provide with basic information on Dioscorea diseases. Infected leaves showing anthracnose and rust symptoms were collected for pathogens isolation on Potato Dextrose Agar (PDA). Different field symptoms of anthracnose such as dark brown or black lesions or large gray lesions bordered by an olive green patch starting from lamina edge extending inwards observed on leaves of some cultivars. Blighted appearance with large purple blotch or dark brown burnt leaf surface, sometimes on petioles followed by die-back of the stem in highly susceptible cultivars. Rust symptoms appeared initially as small pale spots which become yellow with a small dark centre on leaves of D. esculenta species. These spots enlarged

MICRO PROPAGATION OF ANTHURIUM VARIETIES 69 and forming pustules. The pustules are brown or brownish red colour, circular or oval shape and 2.0-2.3 mm in diameter and appeared first and more abundantly on under surface of the leaves and ruptured to expose masses of urediniospores. Severely infected leaves became necrotic and dry but tended to remain attached to the plant.

Visual and microscopic studies showed that Colletotricum isolates taken from different varieties belonging to D. alata produced different growth patterns, colony colour and other morphological characters in cultures. The conidia shape varied from, cylindrical to fusiform with obtuse to pointed ends, hyaline, aseptate and differed with different isolates. All isolates studied possessed key features in cultures, which Mordue, 1971 describe as typical for C. gloeosporioides. The microscopic observation of urediniospores collected from rust leaves are globose, subglobose, ellipsoid, hyaline and pale yellow to chestnut brown and mean sounding 18-28 pm length x 16-23pm width. These urediniospores and teliospores taxonomically very similar to Goplana dioscoreae Cummins (Chung et al, 2009). Anthracnose and rust of Dioscorea have been identified as two fungal diseases caused by C. gloeosporioidies Penz. and Goplana dioscoreae Cummins, respectively, in Sri Lanka and their pathogencity was established.

Sixteen Dioscorea cultivars belonging to five Dioscorea spp. currently grown in Sri Lanka were evaluated for their response to anthracnose and rust diseases under natural artificial conditions. The disease incidence and severity were recorded at weekly intervals until harvesting stage. All the varieties of D. alata were highly susceptible and D. bulbifera moderately resistance to Anthracnose. Two out of 5 species D. rotundata and D. pentaphylla and which were free of infection of anthracnose under natural infection and artificial inoculation as well, were recorded as highly resistant to anthracnose. All varieties belonging to D. esculanta, except “Nattala” were resistant to anthracnose. Cultivars; “Nattala”, “Mahakukulala” and “Sutakukulala” belonging D. esculanta were highly susceptible to rust disease and the rest of the Dioscorea species (D. alata, D. bulbifera, D. pentaphylla and D. rotundata) and were resistant to rust.

REFERENCES

Amusa, N.A., Adegbite, A.A., Muhammed S. and Baiyewu, R.A. 2003.Yam diseases and its management in Nigeria. African Journal of Biotechnology. 2 (12): 497-502. Chung, W., Y. Ono, M. Kakishima and J. Hung. 2009. The New Geographical Distribution of Rust Fungi from Taiwan. Taiwania, 54(3): 279-282. Mordue, J.E.M. 1971. Collectotrichum gloeosporioides. Descriptions of Pathogenic fungi and Bacteria. The Commonwealth Mycological Inst. Kew, Surrey, England. Pp 315. Thavabalachandran, M. and K.P.U. de Silva. 2013. Raja ala and Kakulu ala: Two New Improved Varieties of Greater Yam. Journal of Root Crops. 39 (2). 29-34.

Annals of Sri Lanka Department of Agriculture 2016. 18: 70 - 49

ESTIMATION OF PHENOTYPIC DIVERSITY OF CHILLI (CAPSICUM SPP.) GERMPLASM IN SRI LANKA

B.M.K. SENARATHNE MENIKE, W.M.R. KUMARI, H.M.S.N. HERATH

AND H.M.S. BANDARA

Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka

EXTENDED ABSTRACT Chilli (Capsicum Spp.) is an important cash crop with high market value for its taste, aroma and pungency. A wide range of genotypic variability exists in this crop (Nandi, 1992; Munshi and Behera, 2000). This variability can be utilized for crop improvement programs. Chilli is a diploid (2n=24) species and genetically self-pollinated plant. However, 2 to 96% out-crossing has been observed under open pollination (Hasanuzzaman et al., 2012). There are approximately 25 species within the genus Capsicum, five of which have been domesticated. The most widely grown and economically important species is Capsicum annuum. The four other domesticated species are C. baccatum, C. pubescens, C. chinense and C. frutescence. Study of genetic diversity within available genetic resources is essential to understand the evolutionary and genetic relationship among accessions. A wide diversity exists in morphological traits such as fruit shapes in chilli, both within and between species. Study of genetic diversity within available genetic resources is essential to understand the evolutionary and genetic relationship among accessions. Characterized and evaluated genotypes are essential for an effective breeding program to incorporate desired traits. Germplasm resource contains unique traits/genes that can be utilized for further crop improvement. Exploration, collection and evaluation of germplasm are the quickest and simplest method for acquiring the desired ones for future breeding programmes.

Therefore, in this field study thirty eight chilli (Capsicum spp.) genotypes were evaluated to assess genetic diversity of Capsicum spp. in a Randomized Complete Block Design with two replications during Yala 2015 and Maha 2015/16 seasons at the Field Crops Research and Development Institute (FCRDI), Mahailluppallama. Fourteen morphological characters were recorded, namely, number of days to 50% flowering, plant height (cm), plant breadth (cm), mature leaf length (cm), mature leaf width (cm), pod length (cm), pod girth (cm), pericarp thickness (mm), number of pods per plant, individual pod weight (g), number of seeds per pod and pod yield (t/ha).Analysis of variance, Multivariate data analytical methods viz. principal component and cluster analysis and Pearson correlation coefficient was performed to estimate phenotypic diversity of chilli genotypes accounting fourteen morphological traits.

Out of 38 genotypes with 14 morphological traits, the highest variation was

ESTIMATION OF PHENOTYPIC DIVERSITY OF CHILLI GERMPLASM 71 observed in pods per plant followed by seeds per pod and days to 50% flowering. Moderate variation was observed in plant height and plant breadth. Lowest variation was observed in pericarp thickness of the pods. Analysis of variance revealed significant differences at 0.05% probability level among different genotypes in days to 50 % flowering, plant height, plant breadth, number of pods per plant, individual pod weight, seeds per pod and yield scored. Principal component analysis quantifies each trait to calculate the Principal Components (PCs) which help in describing grouping of variables.

The first principal component (PC1) is related to mature leaf length, leaf width, pod length, pod weight and yield. It explained 39% of total variability. The second principal component (PC2) is related to pod width, pericarp thickness and secondary branches explained 15% of total variability. The third principal component (PC3) is related to morphological characters such as number of primary branches, number of pods per plant and yield. These four components explained more than 75% of total variability among the chilli genotypes evaluated. Leaf characters (length and width), pod length, pod width and yield were recorded higher magnitudes (above 0.35) for the PC1. Leaf characters were positively correlated with PC1. Furthermore, pod width, pericarp thickness were negatively correlated with a high magnitude for PC2 while pods per plant were recorded high positive magnitude for PC2.

The phenotypic tree derived based on Pearson distance explain the relative positions of chilli genotypes scored on morphological traits. At 40 similarity levels, there were six clusters with three main clusters and minor clusters. Germplasm of Capsicum annuum was grouped in to I, II and III clusters. In first cluster, variety MI2 stayed separately. In second cluster Hot Beauty having foreign origin stayed distantly to others. At this similarity level, MI Waraniya1and ICPN 987.5 lines were grouped together which possess same morphological characters like long pod character. Capsicum chinense and C. frutescence lines were clustered separately at cluster IV and V. The line of kochchi 13 which belongs to C. frutescence was stayed separately at cluster VI. It has shown unique characteristic and genetically distance to others.

The derived phenotypic tree revealed that there is a genetically distinctness of parents. Genetic diversity within closely located genotypesis lower than that of distantly located genotypes. The distance parents with different genetic constitution can be utilized for future breeding programmes. In intra-specific crosses of C. annuum, germplasm of cluster I (MICH 3, Galkiriyagama selection and MI2) could be used with germplasm of cluster II (KA2, Arunalu, MI Hot etc.) and cluster III (MI Waraniya1and ICPN 987.5 lines). For inter-specific crosses the germplasm of cluster I, II and III which belong to C. annuum could be combined with germplasm of cluster IV, V and VI which belong to C. chinense and C. frutescence to have new genetic makeup.

72 SENARATHNE MENIKE et al.

The first two major principal components that accounts 54% of the total variance were plotted to observe the relationship between clusters in a Score Plot. All genotypes in cluster I were grouped together in score plot. Germplams of cluster II were closely stayed in the score plot except variety PC 1. Genotypes of cluster IV showed a close relationship. Genotypes of minor cluster of III i.e. MI Waraniya 1 and ICPN 985.7 were stayed closely. Minor clusters of V i.e. Kochchi 7 and Kochchi 15 were also stayed closely. Results of score plot confirm the pattern found in cluster analysis. Thus, there is a potential of utilizing such variability in future chilli crop improvement programmes. Pearson correlation coefficient were shown significant positive correlations between leaf related characters, plant breath, pod width, pericarp thickness, secondary branches per plant, weight per pod and yield with most of morphological traits.

Yield is complex character influenced by a number of other component characters (Jose and Khader, 2002). Weight per fruit and number of fruits per plant are the most important components of yield. Thus, in the process of selection, emphasis should be given to those characters. Other yield components that can be used to improve yield are plant width, fruit length, fruit diameter, days to fruit set and fruit density. (Ahamed and Hurra, 2000). Higher phenotypic and genotypic coefficients of variation were observed for leaf area, fruits per plant, fruit weight, fruit length, fruit girth and yield per plant. High heritability coupled with high genetic advance observed in these characters implies their potential for crop improvement through selection process.

Principal component analysis and cluster analysis have given comparable results for 38 chilli germplasm and score plot has confirmed the aforesaid results. Therefore, estimation of diversity with respective to quantitative traits such as plant breath, leaf characters, pod length, pod width, pericarp thickness, pod weight, secondary branches per plant and yield will help to identify parental materials for future chilli crop improvement programmes. High genetic variation can be created with more genetic distant parents in order to achieve maximum heterosis. REFERENCES

Ahamed, N. and Hurra, M 2000.Heterosis studies for fruit yield and some economic characters in sweet pepper (Capsicum annuum L.) Capsicum and Eggplant Newsletter, 21: 22-24 pp. Hasanuzzaman, M., Hakim, M.A. and Jannatul Fersdous, Islam, M.M. and Rahman, L. (2012).Combining ability and heritability analysis for yield and yield contributing characters in chilli (Capsicum annuum ) landraces. Jose, L. and Khader, A. 2002. Correlation and path coefficient analysis in chilli ( Capsicum annuumL.). Capsicum and Eggplant Newsletter, 21: 56-59 pp. Munshi, A.D. and Behera, T.K. 2000.Genetic variability, heritability and genetic advance for some traits in chillies (Capsicum annuum L.).Vegetable Sci., 27: 39 - 41 Nandi, A. 1992.Genetic variability in chilli Capsicum annuum. Indian Cocoa Arecanut Spices J., 16: 104-105.

Annals of Sri Lanka Department of Agriculture 2016. 18: 73 - 49

A PROMISING EARLY MATURING, CONFECTIONARY TYPE GROUNDNUT (ARACHISHYPOGAEA L.) VARIETY WELL ADAPTABLE TO LOCAL CROPPING SYSTEMS IN SRI LANKA

Y.P.J. AMARASINGHE, D.G.C. JEEWANI, M.T. GUNASENA, W.M.P.N. DILUSHA, R.A.A. RANATUNGA, G. WIJESINGHE, G.T.N. GUNASEKARA AND R.W. PUSHPAKUMARA

Grain Legumes & Oil Crops Research & Development Centre, Angunakolapelessa, Sri Lanka

EXTENDED ABSTRACT

Groundnut is considered as an important source of edible oil throughout the world, in which nutritionally unique and healthy. Groundnut cultivation in Sri Lanka is in increasing trend. In recent years Jumbo peanuts has become popular within the country. But the total requirement for the jumbo peanut production is imported from other countries. As there is a demand for confectionary groundnut at present, development of varieties acceptable for local conditions is a timely need. Therefore present experiments were conducted to identify a promising large seeded groundnut variety suitable for local cropping systems in Sri Lanka.

Eighteen large seeded groundnut lines received from International Crops Research Institute for Semi Arid Tropics (ICRISAT) were evaluated and six lines were advanced to yield trials at GLORDC, Angunakolapelessa and tested for three consecutive seasons. National Co-ordinated Variety Testing (NCVT) and Variety Adaptability Trials (VAT) were conducted since the year 2011 to 2015. Four promising lines (ICGV 05200, ICGV 05198, ICGV 06216 and ICGV 06189) were advanced to NCVT and two promising lines (ICGV 05200 and ICGV 05198) were selected for VAT along with the check variety Walawa. Pod yield data were analyzed using the ANOVA procedure in Statistical Analysis Software 9.1.3 (SAS) and means were compared using least significant difference. Stability of the lines was calculated using the ranking method proposed by Abesiriwardhana et al . (1991). Sensory evaluation was analyzed by Freidman nonparametric techniques by using SPSS windows 16.1. Considering Pod yield, Days to maturity and 100 Seed weight four lines (ICGV 05200, ICGV 05198, ICGV 06189 and ICGV 06216) were advanced for the NCVT (Table 1). Considering the results of all NCVT trials and with an informal sensory evaluation, two promising lines namely ICGV 05198 and ICGV 05200 were nominated for the Varietal Adaptability Trials (VAT).

ASSESSMENT OF GENETIC DIVERSITY AMONG SUWANDAL RICE ACCESSIONS 74

Table 1. Mean Pod Yield (kg/ha), Days to Maturity and 100 Seed Weight (g) of tested lines at GLORDC, Angunakolapelessa. Accession Mean Pod Yield (kg/ha) Days to Maturity 100 seed weight Number/ Variety name 2011/12 2012 yala 2012/13 2011/12 2012 2012/13 Average *STD Range maha maha maha yala maha (g) ICGV 05198 1,955.6 d 2,529.2 a 2,733.3 120 125 120 83.0 14.1 93 -73 ab ICGV 06216 4,440.3 a 2,447.2 a 2,818.0 a 124 130 125 82.5 10.6 90 -75 ICGV 06189 3,366.7 b 1,402.8 b 3,176.7 a 130 126 132 77.8 8.8 84 -71 ICGV 05200 2,065.3 d 965.3 c 2,157.0 b 115 112 115 79.0 1.4 78 -80 ICGV 06229 4,288.9 a 666.7 666.7 c 132 125 130 74.0 2.8 76 -72 cd ICGV 06227 3,194.4 be 651.4 2,747.3 135 128 125 77.5 3.5 80 -75 cd ab Zambia 2,598.6 cd 422.2 d 422.3 c 132 130 132 69.5 0.7 69 -70

Walawa (Check) 3,005.6 be 772.2 2,582.0 136 68.0 0.7 67 -68 cd ab CV % LSD 13.7 18.20 15.70 751.4 393.08 598.43 Note: means followed by the same letter are not significantly different at p=0.05; *STD: Standard Deviation

76 WASALA et al. Table 2: Pod yield (kg/ha) and adaptability rank of tested lines in NCVT 2013/14 Maha.

Locations and ranks Variance Mean Overall Variety/line Vavuniya Angunakola Aralaganwila rank rank Yield Rank Yield Rank Yield Rank (kg/ha) (kg/ha) (kg/ha) ICGV 05200 1,326.5a 6 3271ab 5.5 1,543.2a 6 0.083 5.8 2 ICGV 06189 1,322.2a 6 3301.2ab 5.5 1,666.7a 6 0.083 5.8 2 ; ICGV 06216 1,385.2a 6 3029ab 5.5 1,432.1a 6 0.083 5.8 2 | ICGV 05198 1.174.7a 6 3754.9a 6.0 1.728.4a 6 0.00 6.0 1 Walawa(chcck) 1.209.3a 6 2.369.8b 5.0 1.370.4a 6 ..... 0.33 .... 5.6 3 Indi(check) 796.9b 5 980.2c 4.0 1,364.2a 6 1.00 5.0 4 Note: means followed by the same letter are not significantly different at p=0.05

Table 3: Average Pod Yield (kg/ha) and adaptability rank of two testing lines with comparison to the standard variety walawawhen tested over three locations in 2014 yala. Locations and ranks Variety Kalpitiya Days to Galkulama Days to Panwewa Days to Overall maturity maturity maturity rank ICGV 05200 4,074 a 116 4,888.9 a 112 1,492.5 ab 114 2 ICGV 05198 4,044.4 a 124 4,148.1 a 120 1,625.1 a 125 1 Walawa 2,799.9 b 132 3,629.6 b 135 1,010.2 b 132 3

CV% 9.5 13.5 17.2

LSD 790.8 1,300.7 538.7 Note: means followed by the same letter are not significantly different at p=0.05 .

ASSESSMENT OF GENETIC DIVERSITY AMONG SUWANDAL RICE ACCESSIONS 77

Table 4: Median ranks for sensory evaluation of jumbo type roasted groundnuts. Tested samples Colour Taste Size of seed Crunchiness Overall Acceptability ICGV 05200 1.50a 1.00b 1.50a 1.00a 1.00b Market product 1.00a 2.00a 1.50a 1.50a 2.00a Significance 0.18 0.03 0.31 0.25 0.02 Note: means followed by the same letter are not significantly different at p=0.05.

ICGV 05200 was a promising confectionary type groundnut line, when considering the yield performance and the maturity under NCVT and VAT. It has given a highest yield of 4.8 t/ha during VAT trials and especially this line can be harvested within 105 to 110 days. Sensory properties were compatible with the market type when considering colour, Seed size and crunchiness of ICGV 05200 except taste and overall acceptability, because the processing procedure of market type jumbo peanut was different. The new variety was released as Lanka jumbo, having early maturing ability and it will be a better replacement for Variety Walawa.

REFERENCES

Abesiriwardena, D.S.De Z., R.B. Glenn and F. Reese. 1991. Analysis of Multi environmental yield trials for testing adaptability of Crop genotypes. Tropical Agriculturist, 147: 85-97. Chuni Lal, K. Hariprasanna, M. Bharat . I. Chikani and H.K. Gor, 2014. Inter-allelic interactions in the inheritance of physical-quality traits in peanut (Arachis hypogaea L.) Australian Journal of Crop Science, 1049-1055. DOA. 2002. Recommended Field Crop Varieties (Variety Catalogue Part 1). Department of Agriculture, Sri Lanka.

Annals of Sri Lanka Department of Agriculture 2016. 18: 78 - 45

ASSESSMENT OF GENETIC DIVERSITY AMONG SUWANDAL RICE (ORYZA SATIVA L.) ACCESSIONS BASED ON MORPHOLOGICAL, MOLECULAR AND PHYSICOCHEMICAL CHARACTERISTICS

S.K. WASALA 1, H.M.K.N.K. HENNAYAKE 2, P.G.S.D. GUNASENA 3, S.P. REBEIRA 3, K.M.C.L. KONDASINGHE 1, A.S.J. DANWATTA 1 AND N.M. UBEYSEKARA 1

1 Plant Genetic Resources Centre, Peradeniya, Sri Lanka 2 Faculty of Applied Sciences, University of Sri Jayewardenepura, Sri Lanka 3 Rice Research and Development Institute, Batalagoda, Sri Lanka

EXTENDED ABSTRACT

Plant Genetic Resources Centre (PGRC), Sri Lanka collected and conserves two thousand four hundred seven traditional rice accessions under the six hundred eighty four different cultivars names (gene bank information). Different historical records revealed that traditional rice varieties were revered for their nutritional and medicinal properties. Recently demand for traditional rice cultivars have been increased and consequently extend of cultivation also considerably increased. According to the farmer preference and consumer demand seven traditional rice cultivars have been identified for cultivation. However, due to poor quality seeds and large number of accessions coming under one cultivar name correct identification and quality seed paddy production with identical qualities are prerequisite.

Suwandal is one of the popular traditional rice cultivars with a special kind of aroma and taste. At present 14 rice accession under the name of Suwandal were explored from different parts of the country and conserved at PGRC genebank. However, systematic studies were not conducted to study the diversity among these accessions and identify the repetitions. Therefore, present study was conducted to characterize these accessions using morphological, molecular and physicochemical characters to identify the available diversity, and identify suwandal accessions with identical characters for quality seed production and popularize among farmers.

Suwandal rice accessions which conserved at seed gene bank of PGRC were established in the in Yala 2015 and Maha 2015/16 in the field at PGRC. Twenty six qualitative and seventeen quantitative morphological characterized data were recorded at vegetative stage, flowering stage and at maturity according to the standard descriptor for rice (PGRC, 1995). DNA was extracted from two weeks old immature leaves of these Suwandal accessions using modified CTAB method and molecular characterization was done using 30 microsatellite markers (Wasala et al., 2012). Physical and physicochemical quality characterization was done at Rice Research and Development Institute, Batalagoda (Rebeira et al., 2014). Cluster analysis and Principle Component Analysis (PCA) were done for morphological data. Molecular

ASSESSMENT OF GENETIC DIVERSITY AMONG SUWANDAL RICE ACCESSIONS 79 data were analyzed using POWERMARKER V 3.25 software. These data were used to construct a phylogenetic tree based on Unweighted Paired Group Method with Arithmetic Average (UPGMA) algorithm. Analysis of variance was performed for physicochemical data and mean separation was done according to the Turkey’s T test.

Culm strength (i.e. lodging resistance) and culm angles, leaf pubescence, leaf angle, ligule shape, panicle characters, floral and seed characters were varied among the accessions. Considerable variation of seed coat colour was shown. Quantitative data revealed that these Suwandal accessions belong to the different maturity groups. Distinct variations were observed in plant height, ligule length, grain weight, grain length and width. The first 4 principle components explained 91.5% of the total variability.

According to the molecular analysis a total of 82 alleles were detected at 30 microsatellite markers across 14 Suwandel rice accessions. Out of these 30 SSR loci 28 loci showed polymorphism. Allele richness varied from 1 (RM 255 & RM 228) to 5 (RM 202) alleles across tested populations. A high level of genetic diversity existed among 30 loci studied across 11 Suwandel rice accessions. It ranged from 0.00 to 0.75 with an average of 0.44. The PIC value of each marker could be evaluated basis of allele frequencies. It varied from 0.0 (RM255 and RM228) to 0.71(RM202) with the average of 0.38.

Genetic distances showed considerable variation and none of the accession pair showed zero genetic distance. It concludes that even though accessions identified with the similar name there were no duplicates in genetic level In this study tested accessions were obtained from various agro- climatic regions of the country and evolve through long process under different environmental conditions hence genetic divergence can be occurred. Similar results were obtained by Ahmed et al., (2015) for different accessions of Dhaliboro rice cultivar at Bangladesh

Physicochemical properties of tested accessions varied among the accessions. Except AC05420 rest of the tested accessions grouped into the high (>25%) amylose content. Gel consistency which indicates the texture of cooked rice of these tested accessions ranged from 3.4 to 5.1. Except AC04197 (5.1) rest of the accessions gave high gel consistency value (<4). Except AC12844 rest of the accessions showed intermediate

80 WASALA et al. gelatinization temperature values. Percentage free radical scavenging activity value ranged from 34.6 (AC13300) to 87.5 (AC05420). AC05420 and AC4595 showed over 87 % free radical scavenging activity.

Based on morphological molecular and physicochemical characterized data, no duplicates were identified among these conserved Suwandal accessions. AC12844 showed distinctly different characters and it can be a miss identified cultivar. AC13300, AC11340 and AC12827 showed close relationship both under morphological and molecular data which comes under 3.5 month age group. AC04197, AC04595 & AC04802 made another group with close relationship which comes under 5 month age group. Physicochemical activity of these tested accessions showed significant variation among the accessions and it is not reflected by the morphological and molecular diversity.

REFERENCES

Ahmed, M. S., S. Parveen, M.H.K. Baktiar and M.A. Siddique. 2015. Study of quantitative agromorphological characters of Dhaliboro rice (Oryza sativa L.) germplasm of Bangladesh. Eco-friendly Agriculture Journal 8(08): 91-96. Anon 1995. Descriptors for cereals. Plant Genetic Resources Centre, Department of Agriculture, Sri Lanka: 4-21. Rebeira, S.P., H.A.M. Wickramasinghe, W.L.G. Samarasinghe and B.D.R. Prashantha. (2014) Diversity of grain quality characteristics of traditional rice (Oryza sativa L.) varieties in Sri Lanka. Tropical Agricultural Research 25 (4): 570-578. Wasala Samanthi K, S.R.T.P. Senanayake and S.M.S.W. Wanigadewa. 2012. DNA fingerprinting of traditional rice (Oryza sativa L.) accessions for diversity analysis and cultivar identification. Annals of the Sri Lanka Department of Agriculture. 14: 187-196.

Annals of Sri Lanka Department of Agriculture 2016. 18: 81 - 49

EFFECT OF DIFFERENT WATER REGIMES ON YIELD AND WATER USE OF RED ONION (ALLIUM CEPA) GROWN UNDER NON-CALCIC BROWN SOILS ( HAPLUSTALF) IN THE LOW COUNTRY DRY ZONE OF SRI LANKA

A.G. CHANDRAPALA 1, S.H.S.A. DE SILVA 1 AND N.D. RANAWAKA 2

1 Natural Resources Management Centre, Peradeniya, Sri Lanka 2 In-Service Training Institute, Gannoruwa, Sri Lanka

EXTENDED ABSTRACT

Irrigation water shortage still remains as one of the major limiting factors for agricultural production even in major irrigation schemes. As the multiphase large diversion projects and other major irrigation schemes are already exploited, the phase of expansion in the country’s irrigated area have become limited (IIMI, 1992). The emphasis now is on increasing water use efficiency of the existing irrigation systems and efficient on-farm water management for higher productivity. Hence, present study was conducted to identify appropriate irrigation water regime, in terms of yield, yield attributes of red onion and water use efficiency with straw mulch and compost.

The effect of six irrigation regimes based on IW/CPE ratio with presence or absence of rice straw mulch (10 t/ha) and compost (10 t/ha) on yield of red onion and water use efficiency was tested in a split-split plot design with three replicates at the Regional Agricultural Research and Development Centre, Aralaganwila (DL 2b agroecological region). Different IW/CPE ratio (0.25, 0.5, 0.75, 1.0, 1.25 and 1.5) were the main plot treatment, while presence or absence of rice straw mulch (10 t/ha) were the sub plot treatments. Presence or absence of Compost (10 t/ha) was the sub-sub plot treatment.

Red onion (cv. Vethalam) was planted at the spacing of 10 x 10 cm and crop management practices were adopted as the recommendation of the Department of Agriculture (DOA, 1990). The total rainfall received during yala 2010 and 2011 was 334 mm and 113 mm respectively. Daily rainfall amount and evapotranspiration rates were measured using recording type rain-gauge and class A evaporation pan. Irrigation water was applied based on daily evapotranspiration rate and crop coefficient (Kc) relevant to different growth stages as follows; initial stage, 25 days (0.5), Growth stage, 40 days (0.7), mid stage, 20 days (1.8) and maturity stage, 10 days (1.0) (FAO, 1992).

Leaf relative water content was measured in 3 weeks interval and calculated

82 CHANDRAPALA et al. using the following formula (Turner, 1981): LRWC (%) = [(F.W - D.W) / (T.W - D.W)] x 100 ...... eq. (1)

Where, LRWC (%) = Leaf relative water content, FW = fresh weight leaves, DW = dry weight leaves, TW = Turgid weight.

Composite soil samples were collected just before the irrigation up to 20 cm depth in soil in each plot at 3 weeks interval to determine the gravimetric soil moisture content. Ten tagged representative plants were harvested from each plot for recording yield attributes of onion. The water use efficiency, as kg of onion bulb yield per cubic meter of water used was calculated by dividing the bulb yield of red onion with total water used as irrigation and rainfall.

According to the results, among the different water regimes tested, IW/CPE ratio 1.5 (M 6) recorded the significantly highest number of bulbs per plant, weight per bulb and bulb yield during both the years The lowest yield parameters were recorded with irrigation at 0.25 IW/CPE ratio. There was no significant difference of bulb yield among the IW/CPE ratio of 0.75, 1 and 1.25. Application of mulch and compost significantly increased the red onion yield and yield components in both seasons. Significant interaction between different water regimes and application of mulch on yield and yield components of red onion was not observed. Application of compost (10t/ha) also significantly increased the crop yield and yield components (except bulbs per cluster) of red onion in both seasons. There was also no significant interaction between different water regimes and application of compost on crop yield and yield components except weight of one bulb. Significantly higher number of Plants/m 2of red onion at 9 weeks after planting was recorded by the IW/CPE ratio 1.5 followed by IW/CPE ratio of 1.25 and 1. However, significant mulch effect or compost effect on number of plants/m 2 was not observed. There was a significant interaction between application of mulch and compost on number of plants/m 2. This is mainly due to the higher number of plants under nonmulch treatment over mulched treatment only in compost applied plots

Among the different water regimes tested, IW/CPE ratio of1.5 recorded the highest leaf relative water content at 3, 6, and 9 weeks after planting in both the years. There was a significant difference of leaf relative water content among different water regimes except IW/CPE ratio of 1 and 1.5 in year 2010 where there was no difference in Leaf Relative Water Content. Lowest Leaf Relative Water Content was recorded in IW/CPE ratio of 0.25. Application of mulch and compost also increased the leaf relative water content in both the years. There was a significant interaction exist between water

FFECT OF WATER REGIMES ON YIELD OF RED ONION 83 regimes and application of mulch in both years, except 6 weeks after planting, where interaction was not significant. Leaf Relative Water content varies in wider range (42.1 to 92.7 at 3 weeks after planting and 49.4 to 76.7 at 9 weeks after planting in year 2010) in mulched treatment than the non-mulched treatment (38.2 to 79.5 at 6 weeks after planting and 48.4 to 64.6 at 9 weeks after planting in year 2010).

There was also a significant interaction exists between application of mulch and compost on leaf relative water content. Under the application of compost, there was a wide range of Leaf Relative Water Content (53.8 to 63. 0 at 3 weeks after planting and 56.4 to 64.8 at 6 weeks after planting). However, without application of compost, Leaf Relative Water Content varied in a narrow range (56.2 to 60.6 at 3 weeks after planting and 54.86 to 58.7 at 6 weeks after planting). Significantly higher gravimetric soil moisture content at 3, 6 and 9 weeks after planting in both 2010 and 2011 years were recorded by the IW/CPE ratio of 1.5 and 1.25. However, there was a significant increase of gravimetric soil moisture content at 3, 6 and 9 weeks after planting under mulch and compost application in both the years.

In year 2010 Yala season received 334.5 mm of rainfall compared to 113.0 mm in 2011 Yala season. Generally, water use efficiency in 2010 Yala season was lower than year 2011. In year 2010, when effective rainfall was higher, significantly highest water use efficiency was recorded in highest water regime (IW/CPE ratio 1.5). In contrast, when effective rainfall was lower, highest water use efficiency was recorded in lowest water regime (0.25 IW/CPE ratio). Majority of rainfall received at the beginning of planting and crop harvesting stage in both 2010 and 2011 Yala seasons. However, when there was relatively low amount of effective rainfall, contrasting results were observed. Although, contrasting results of water use efficiency among water regimes were observed in two seasons, there was significantly higher water use efficiency of red onion under straw mulching and compost application in both the years.

Based on the results, it was concluded that application of straw mulch and compost have an increasing effect on red onion yield, leaf relative water content, gravimetric soil moisture content and water use efficiency. However, since highest red onion bulb yield, yield components, soil and plant moisture status were recorded in highest soil moisture regime (1.5 IW/CPE ratio) tested, further studies are needed to find out the optimum water regime to achieve maximum crop yield and water use efficiency in sandy non-calcic brown soil in the low country dry zone of Sri Lanka.

84 CHANDRAPALA et al.

REFERENCES

Department of Agriculture., (1990). Crop Recommendations Techno guide. Department of Agriculture, Peradeniya, Sri Lanka. p. 46 FAO, (1992). Irrigation and Drainage Paper. No. 36. IIMI, (1992). Annual Report, International Irrigation Management Institute, Colombo Turner, N.C. (1981). Techniques and experimental approaches for the measurement of plant water stress. Plant Soil, 58: 339-366.

Annals of Sri Lanka Department of Agriculture 2016. 18: 85 - 45

EFFECT OF IRRIGATION INTERVALS ON GROWTH AND YIELD OF CLUSTER ONION IN NON-CALCIC BROWN SOILS

D.G.P.S. DELPITIYA 1, S.H.S.A. DE SILVA 2, R.A.C.J. PERERA 3, P.G.T.L. MADUMALI 4, H.A.P. JAYALATH 1 AND W.M.D.N. WEERASINGHE 1

1 Regional Agriculture Research and Development Centre, Aralaganwila, Sri Lanka 2 Natural Resource Management Centre, Peradeniya, Sri Lanka 3Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka 4Inter Provincial Extension Office, Polonnaruwa, Sri Lanka

EXTENDED ABSTRACT

Cluster Onion (Allium cepa L. ) is a bulbous crop cultivated in almost all over the world. Even in Sri Lanka it’s a very popular crop that is broadly cultivating in northern and southern regions. In Sri Lanka, cluster onion has cultivated in 4872 hectares with total production of 63,037 tons red onion bulbs (Agstat, 2015). Non-Calcic Brown soil is a sandy soil having a sand percentage of around 90% and less water retention ability, around 10.10% available water at the surface layer according to Mapa and Bodhinayake (1988). Therefore, frequent irrigation is required for any crop grown in this soil. Most of the red onion cultivating farmers irrigates fields every day. Application of water frequently to the crop is always increase the cost and increase disease incidences. Therefore, this study was conducted with the objective of finding the appropriate irrigation interval for cluster onion in Non-Calcic Brown soil to enhance the water productivity while reducing the cost for irrigation.

A field experiment was carried out at Regional Agriculture Research and Development Centre, Aralaganwila in 2012/13 Maha and 2013 Yala seasons in NonCalcic Brown soil. The treatments were allocated in 3X 1m plots with three replicates.Each plot was separated from 1m width space and a polythene was laid between the plots up to 50 cm depth to avoid the lateral movement of water from plot to plot. Irrigation intervals were selected as one, two, three, four and five days and amount of water irrigated was determined according to the evaporation data. The amount irrigation for each interval was calculated based on climatological approach using the crop coefficients (Kc) for cluster onion and daily evapotranspiration data.

Gravimetric soil moisture content was determined at 0-20cm depth class prior to each irrigation and Soil bulk density was determined. Soil moisture depletion’s were determined using those data. The irrigation water use efficiency (IWUE) also calculated. Vegetative growth parameters and Yield parameters were measured and compared statistically using SAS software.

86 DELPITIYA et al.

According to growth data, there’s no significant difference in No of bulbs/ cluster and height of plants. Only in 2013 yala season number of bulbs/cluster have reduced in 5 days irrigation with compared to one day irrigation interval at maturity stage. In both maha and yala seasons there’s no significant difference among the treatments in yield however in maha season there can be an affect from the rains. In yala season highest mean yield of 15.85 t/ha and highest IWUE was observed in three days irrigation interval treatment. Mean cluster onion yield was reduced by 37% (5.88 t/ha) and 32% (5.04 t/ha) with the increase of irrigation interval from 3 days to 4 days and 3 days to 5 days respectively.

Hanson et al . (2007) has reported that approximate allowable soil moisture depletion for onion is 25% and Maughan et al. (2015) also reported that the amount of allowable depletion for onions is about 25 to 30% of the total available water in the soil. In this study the volumetric soil moisture depletion level was 20% with three days irrigation interval (Figure 1). Therefore, three days irrigation interval is optimum to avoid moisture stress to the plant.

Figure 1: Average Soil volumetric moisture contents % day before irrigation in all observations with different irrigation intervals

It has being recorded that farm gate price of red onion in 2013 was Rs. 124.27/kg (AgStat, 2014). Economic return was calculated using above figure under different treatments. When considering the results in Yala season which is least affected by rainfall, the gross income is reducing by about Rs. 7,00,000.00/ha when increasing the irrigation interval from 3 days to 4 and 5 days. When increase irrigation interval by a day labour cost for irrigation is also reducing. With considering yield parameters, soil moisture depletion levels and economic returns, three days irrigation interval is the most suitable. Therefore, irrigation interval can be increase up to 3 days without affecting the crop yield while increasing the water productivity and can reduce the cost of cultivation of cluster onion in Non-Calcic Brown soils.

IRRIGATION INTERVALS EFFECTS ON GROWTH AND YIELD OF CLUSTER ONION 87 ACKNOWLEDGEMENT

We sincerely acknowledge the financial support given by the National Agriculture Research Policy (NARP), Sri Lanka.

REFERANCES

Agstat (2014). Pocket book of agriculture statistics. V 11. Socio Economics and Planning Centre, Department of Agriculture, Peradeniya, Sri Lanka. Agstat (2015). Pocket book of agriculture statistics. V 12. Socio Economics and Planning Centre, Department of Agriculture, Peradeniya, Sri Lanka. Hanson, B., S. Orloff and B. Sanden. (2007). Monitoring Soil Moisture for Irrigation Water Management. University of California Agriculture and Natural Resources. California. 10p. Mapa, R.B. and W.L. Bodhinayake. (1988). Characterization of Soil Moisture Retention Relationship in Non-Calcic Brown Soils (Haplustalfs). Tropical Agriculturist. 144:145150. Maughan, T., D. Drost and L. Niel. (2015). Vegetable Irrigation: Onion. Accessed on 2016.04.28 from http://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1720&con text= extension_curall

Annals of Sri Lanka Department of Agriculture 2016. 18: 88 - 49

EFFECT OF FUNGICIDES ON MANAGEMENT OF FUNGAL BULB ROT IN CLUSTER ONION

M.S.W. FERNANDO S.H.S.A. DE SILVA 2, B. BAVALEESWARAN 3 S. KANCHANA 1 AND R.M.C. SUDUMANIKE 4

1 Regional Agricultural Research and Development Centre, Aralaganwila, Sri Lanka 2 Natural Resource Management Centre, Peradeniya, Sri Lanka 3 Agriculture Research Station Thirunelvely, Sri Lanka 4 In-service Training Centre, Hansayapalama, Polonnaruwa, Sri Lanka

EXTENDED ABSTRACT

Onion (Allium cepa L.) is one of the important condiment and cash crop grown in Sri Lanka. The average yield of cluster onion in Sri Lanka ranged from 11 to 15 t/ha. It has been reported that there are several factors affect the yield of cluster onion. Among them, occurrence of fungal bulb rot is the key factor that effect on yield losses of cluster onion in the field. The disease is caused by several soil borne pathogens such as Fusarium spp. (Szczech, 1999), Pythium spp. (Veeken et al., 2005), Rhizoctonia solani (Diab et al., 2003), Sclerotium spp. (Coventry et al., 2005). Make use of Homai (Thiophanate methyl 50% + Thiram 30% WP) at the rate of 18 g/10 l or Thiram 80% WP at the rate of 15 g/10 l water for 30 min or Thiophanate-methyl 70% WP at the rate of 20 g/10 l water for 30 min as a bulb treatment at planting is recommended by the Department of Agriculture in Sri Lanka (Pesticide Recommendations, 2015). Meanwhile, adding cow-dung at the rate of 15- 20 t/ha at land preparation showed the low fungal bulb rot incidences in DL 2b agro ecological zone in Sri Lanka (Fernando et al., 2013).

The present study was undertaken to investigate the efficacy of three recommended fungicides and two fungicides which are not recommended for controlling fungal bulb rot, by in vitro and field screening in major cluster onion growing agroecological regions of Sri Lanka, namely, DL 2b and DL 3. The main causal agents of onion bulb rot in DL 2b region i.e. Fusarium spp. and Sclerotium rolfsii were isolated from soil of onion cultivations. This study was conducted to identify suitable fungicides and dipping time of bulbs in fungicide solution for controlling fungal bulb rot in different treatment durations which give the lowest disease incidence with high yields in cluster onion. Field study was conducted at the Regional Agriculture Research and Development Centre (RARDC), Aralaganwila and Agriculture Research Station (ARS), Thirunelvely, two of the main cluster onion growing areas of Sri Lanka. A laboratory screening study was conducted in Yala 2012 season. The main pathogens which are common in research fields were Fusarium spp. and Sclerotium rolfsii. Therefore, isolates of Fusarium spp. and Sclerotium rolfsii from soils of

EFFECT OF FUNGICIDES ON MANAGEMENT OF BULB ROT IN CLUSTER ONION 89 research fields were used for the experiment. Five fungicides which are commonly used in cluster onion cultivations were tested with three replicates in a Complete Random Design (CRD). Those treatments were as Captan 50% WP, 10g/10l (T1), Thiram 80%WP, 15g/10l (T2), Tizca (Fluazinam 500g/l SC), 5ml/10l (T3), Homai (Thiophanate methyl 50% + Thiram 30% WP), 18g/10l (T4), Orius (Tebuconazole 250 ml/l), 3.5 ml/10l (T5). Among the selected fungicides, Captan WP, Thiram WP and Homai WP are recommended fungicides for bulb treatments and others i.e. Fluazinam SC and Tebuconazole are recommended for foliar diseases. Fungicide screening test (in-vitro) was conducted by following food poison technique. The diameters of colonies were measured after 3, 5, and 7 days of the experiment. Then, the mean growth rates of each fungus were calculated. Antifungal Activity Calculation were done with five mm disc from an actively growing culture of each fungi were separately placed in the center of Potato Dextrose Agar (PDA) plate mixed with fungicides. Three replicate plates were used per treatment. Percentage of inhibition was calculated.

Field studies were conducted during Yala 2012 and Maha 2012/13 seasons as a field trail at the RARC Aralaganwila (DL 2b agro-ecological region) and ARS Thirunelvely (DL 3 agro-ecological region) to find out the appropriate combination of fungicides and the bulb treatment time to reduce the fungal bulb rot disease in onion. The experiment plots at Aralaganwila were at a site of the regular cultivation of cluster onion and infected plants, crop residue were also added (Sick plot). Twenty five treatments were tested as combination treatments including five fungicides and five bulb treatment times. Treatments were replicated three times and arranged as a Randomized Complete Block Design (RCBD) at each location and each growing season. Data were recorded on disease incidence (%) by counting total number of plants and diseased plants at weekly intervals since planting up to harvesting. Percent disease incidence (DI %) was calculated.

In vitro screening revealed that there is a significant difference among the fungicides tested (p < 0.0001). The lowest growth rate was shown in culture plates treated with Captan 10g/ 10l for both Fusarium spp. and Sclerotium rolfsii. Homai also showed a similar growth rate as with Captan. Homai is widely used recommended fungicide to the fungal bulb rot in cluster onion cultivations in Sri Lanka. Thiophanate - methyl is highly effective on Fusarium spp. and Sclerotium rolfsii (Pesticide Recommendations, 2015). However, Tizca and Orius did not show effective control on tested fungi and it may be due to they are mainly meant for controlling foliar diseases. Relative inhibition of colony growth results showed that both fungi have significantly better colony growth inhibition in Captan 50% WP and Homai (Thiophanate methyl 50% + Thiram 30% WP) compared to other tested fungicides. Captan 50% WP, a more efficient fungicide resulted in 89.4 % and 90.7% reduction of Fusarium spp. and Sclerotium rolfsii growth, respectively. Homai also showed a similar efficiency with

90 FERNANDO et al.

72.7% and 74.9% reduction with respective fungi. There are significant differences in Homai (Thiophanate methyl 50% + Thiram 30% WP) and Captan 50% WP with Thiram in In- vitro and In- vivo experiments. In both seasons at Thirunelvely there were less than 5% disease incidence level may be due to low pathogen density in that soil under natural infection conditions.

It shows that the fungal bulb rot was not a serious disease under DL 3 climate conditions in both seasons tested. But, in Aralaganwila the disease incidences were comparatively high. It is logical to assume that disease presence and its potential impact on crop would be greater in Aralaganwila than Thirunelvely as the latter does not maintain a sick plot for the disease. Thus, more cluster onion crop residues on soil of sick plot is likely to act as an inoculums source to potentially contribute to high disease infection at Aralaganwila. At the end of the growing season, there were more than 75% and 35% cumulative disease incidences at Aralaganwila during 2012 Yala season and 2012/13 Maha season with some treatments. It hints that the sick plot is rich with fungal bulb rot pathogens. Orius dipped in 24hrs (T25) showed the significant highest DI of >75% in 2012 Yala season. In both seasons, current recommendation bulbs dipped in Homai for 30 min (T16) and Captan for 1hr (T2) gave the similar lower DI values. The T2 had maintained the lowest DI value throughout the season. Results of the experiment repeated in 2012/13 Maha season also confirmed the results obtained in 2012 Yala. Results of field trials conducted during 2012 Yala and 2012/13 Maha seasons have confirmed that Fluazinam 500 g/l SC (Tizca) and Tebuconazole 250 ml/l (Orius) did not show any effective control on tested fungi.

Both treatments of bulbs dipped for 1 hour in Captan 50% WP at the rate of 10 g/10l and Homai (Thiophanate methyl 50% + Thiram 30% WP), 18g/10l in 30 minutes application had shown as the best treatment among the tested treatments for cluster onion in DL 2b agro ecological zone for fungal bulb rot management in field conditions. In - vitro testing also confirmed that the Captan 50% WP and Homai at the same rate are the better fungicides to control Fusarium spp and Sclerotium rolfsii, two main pathogenic fungi causing fungal bulb rot in cluster onion. Therefore, both Captan 50% WP at the rate of 10 g/10l and Homai (Thiophanate methyl 50% + Thiram 30% WP), 18 g/10l in 30 minutes can be recommended as effective fungicides to control fungal bulb rot in cluster onion.

REFERENCES

Coventry, E., Noble, R., Mead, A. and Whipps, J.M., 2005, Suppression of Allium white rot (Sclerotium cepivorum) in different soils using vegetable wastes. European Journal of Plant Pathology 111:101-112. Diab, H., Hu, S. and Benson, D.M., 2003. Suppression of Rhizoctonia solani on impatiens by enhanced microbial activity in composted swine waste amended potting mixes.

EFFECT OF FUNGICIDES ON MANAGEMENT OF BULB ROT IN CLUSTER ONION 91

Phytopathology 93: 1115-1123. Fernando, M.S.W., Silva De S.H.S.A., Ekanayake, K.E.M.N.K., Kanchana, S., Mahindapala, P. and Sudumanike, R.M.C., 2013. Effect of different cowdung levels on fungal bulb rot incidence of cluster onion raised by bulbs. Annals of the Sri Lanka Department of Agriculture 15: 183-194. Pesticide Recommendations, 2015. Department of Agriculture. Peradeniya. Sri Lanka. 48. Szczech, M.M., 1999. Suppressiveness of vermicompost against Fusarium wilts of tomato. Journal of Phytopathology 147:155-161. Veeken, A.H.M., Block, W.J., Curci, F., Coenen, G.C.M., Temorshuizen, A.J. and Hamelers, H. V.M., 2005. Improving quality of composted biowaste to enhance disease suppressiveness of compost-amended, peat based potting mixes. Soil Biology and Biochemistry 37: 2131-2140.

Annals of Sri Lanka Department of Agriculture 2 016. 18: 92 - 49

POPULARITY ASSESSMENT OF RECOMMENDED RICE VARIETIES IN SRI LANKA

D.M. WITHANAWASAM 1 AND N.L. SUDHEERA 2

1 Regional Rice Research & Development Centre, Bombuwela, Sri Lanka 2 Rice Research & Development Institute, Batalagoda, Sri Lanka

EXTENDED ABSTRACT

Rice is the most important food crop for Sri Lankans (Jayawardana et al., 2010). Eighty one rice varieties have been recommended by the Department of Agriculture (DOA) in Sri Lanka by the year 2015. Farmers adopted comparatively better performing varieties and only poorly performed varieties in their paddy fields were withdrawn or replaced by new varieties (Jayawardana et al., 2010). Growing suitable rice varieties with high yield is very important because rice lands are limited in the country. Therefore development of new suitable rice varieties is essential to sustain the rice production. Knowledge of the popularity of rice varieties in Sri Lanka and their characteristics are important particularly to breeders and also to extension officers to plan their future breeding programmes and extension programmes. The objective of the present study was to identify the popular rice varieties of the country and possible reasons for their comparatively higher popularity.

In the present study, secondary data of cultivated rice extents of different varieties were obtained from the Rice Research and Development Institute data bank. Other required information for variety popularity was collected from the extension officers and senior scientists of the Department of Agriculture through a questionnaire. The popularity was determined based on the cultivated extent of each variety over 12 years starting from 2003 and ending in 2014. Varieties with cultivated extent equal or more than 1% to less than 5% in any cropping year was considered as low popular varieties and those equals or more than 5% in any cropping year was considered as most popular. The trend of cultivated extent was determined by regression analysis. In addition the cultivated extent was analyzed regarding the grain size and shape and pericarp colour. Grain yield, days to maturity, lodging assessment, reactions to biotic stresses and some important grain quality aspects of selected varieties were taken from the National Coordinated Rice Varietal Trial (NCRVT) reports to explain the variety spread.

Cultivated extent of rice crop directly measures its popularity among farmers. Twenty one rice varieties with cultivated over more than 1% of land extent were

POPULARITY OF RECOMMENDED RICE VARIETIES IN SRI LANKA 93

considered as popular. Among them only seven varieties are identified as the most popular rice varieties as they have been cultivated over 5% land extent in any year within the study period. Varieties having non-significant Regression Coefficient values (i.e. slope= 0) can be considered having stable trends and varieties having significant regression Coefficient values (i.e. slope 4 0) had either negative or positive variable trends. Coefficient of determination explained the variation in variety spread over the years. At 353 and Ld 356 showed nearly 5% of spread at the beginning but a rapid decrease of popularity after few years (Figure 1). In addition Bg 350, Bw 351, Ld 355, Bg 379-2, Bg 403, Bg 305 and Bg 450 showed decreasing trends in popularity (Figure 1) along with some unfavourable characteristics.

Figure 1. Trends of cultivated extents of low popular rice varieties since 2003.

Trends of cultivated extents of Bg 406 and Bg 357 over 12 years period appeared almost stable (Figure 1). Bg 406 showed always a low extent because it is cultivated perticularly in water available areas. Although Bg 357 is one of the high yielding variety it is not much popular among farmers potentially due to its low bulk density of rough rice and higher breakages of milled rice during pollishing. At 307, At 308 and Bg 366 showed comparatively higher rate of increase in cultivated extent with time (Figure 1) and the Regression Coefficients of them are statistically significant with positive values. Though they have shown a increasing trend of popularity they consist of some unfavarable characters.

The varieties of Bg 352, Bg 300, Bg 362, Bg 358, Bg 94-1, Bg 359 and Bg 360 contributed to 74.5% of the total rice extent and they represented 3% month maturity group except Bg 300 which belonged to 3 month maturity group. There was no significant increase or decrease in cultivated extent of Bg 352, Bg 300 and Bg 359 over 12 years and can be considered to have stable distribution of trend (Figure 2). Furthermore Bg 300 and Bg 352 are the two most popular rice varieties in Sri Lanka.

94 WITHANAWASAM et al.

Varieties, Bg 94-1and Bg 358 showed decreasing trend in cultivated extent with significant negative Regression Coefficient value while At 362 and Bg 360 showed a significant increasing trends (P<0.05) of the extent within reporting period.

Figure 2. Trends of cultivated extents of most popular rice varieties (more than 5% extent)

Popularity of varieties depended on many different factors. Among them earliness and grain yield is prominent. Among the varieties in most popular group, At 362 is the only red pericarp rice variety. It also produces long medium (LM) grains. The potential yield of At 362 can be exploited by practicing good management particularly in the fertile soil of dry zone. Varieties with high head grain percentage (HG%) have an advantage in the market because millers prefer high HG recovery. As per the NCRVT data, Bg 352, Bg 359 and Bg 300 are intermediate bold (IB) grain type varieties with higher average HG%. Bg 94-1 shows the lowest head grain percentage in the most popular variety group. Grain quality characteristics are another important aspect which influences for varietal spread. All the most popular varieties consist of some accepted grain quality characteristics by Sri Lankans. Sensory properties of cooked rice of Bg 352, Bg 300, Bg 94-1and Bg 360 are comparatively higher than other white pericarped long grain rice varieties. Bg 360 is the popular quality rice variety with short round (SR) grain type in Sri Lanka. The most popular rice varieties are affected by several insect pest and diseases. All these varieties are susceptible or moderately susceptible to Bacterial Leaf Blight (BLB) except Bg 360 and At 362. Bg 352 can be affected by Brown Spot, a severe disease in Sri Lanka in both Wet and Dry Zone areas (Mithrasena et al., 2012). Especially Bg 358 is susceptible to neck blast and it may cause considerable yield losses. Bg 94-1 is susceptible for Brown Plant hopper (BPH) and Rice Galle midge (RGM). Lodging is an important parameter for variety selection by farmers. Out of popular varieties At 362, Bg 360 and Bg 94-1 are non lodging while Bg 352 and Bg 300 lodged in some seasons. Bg 358 is highly vulnerable to lodging in every season and even 100% yield loss can be occurred. At present, Bg 300 is the second most popular rice variety and it is considered as the widely adaptable variety as it can be grown well over different agro-ecological zones across the country. As per the pericarp colour and shape of most popular variety group, around 50 % of extent is covered by white long grains. There is a slight increasing trend of red long varieties due to rapid

POPULARITY OF RECOMMENDED RICE VARIETIES IN SRI LANKA 95 spread of variety At 362.

Popularity of rice varieties is complex. Spatial as well as temporal variation of popularity of rice varieties could be seen. Bg 352, Bg 300, At 362, Bg 358, Bg 94-1, Bg 360 and Bg 359 are the most popular varieties among recommended varieties by DOA. Out of them At 362 and Bg 360 showed increasing trends of popularity while Bg 358 and Bg 94-1 showed decreasing trends. However Bg 352, Bg 300 and Bg 359 showed stable trends of popularity while Bg 300 and Bg 352 are the most popular rice varieties in Sri Lanka.

REFERENCES

Jayawardana, S.N., M.M.P. Muthunayake and S.W. Abeysekara. 2010. Present status of varietal spread of rice ( O. sativa L.) in Sri Lanka. Annals of the Sri Lanka Department of Agriculture, 12:247-256. Mithrasena, Y.J.P.K, J.N. Silva, Adikari A.A.W.P, W.M.S.K. Weerasinghe and H.P.D. Sumanasinghe. 2012. Identification and management of brown leaf spot and grain discolouration disease of rice (Oryza sativa L.) in Sri Lanka. Annals of the Sri Lanka Department of Agriculture, 14:77-86. National Coordinated Rice Varietal Trial (NCRVT) seasonal reports. Yala seasons (1999, 2008, 2010, 2011, 2013, 2014) and Maha seasons (1999/2000, 2000/2001, 2006/07, 2007/08, 2008/09, 2010/11, 2011/12, 2012/13, 2013/14), Rice Research & Development Institute, Batalagoda.

Annals of Sri Lanka Depa rtment of Agriculture 2016. 18: 96 - 45

MOLECULAR BREEDING FOR IMPROVEMENT OF BLAST AND SHEATH BLIGHT RESISTANCE IN SRI LANKAN RICE CULTIVAR ‘POKURU SAMBA’

D.S. KEKULANDARA 1, K.R.D. GUNAPALA 1, N.S. THILAKARATHNE 1 AND K.A.G. DEEPIKA 2

1 Rice Research and Development Institute, Bathaalagoda, Sri Lanka. 2 Rajarata University of Sri Lanka, Mihinthale, Sri Lanka.

EXTENDED ABSTRACT

Rice, being the staple food crop, provides about 1.6% of Gross Domestic Products of Sri Lankan economy. Rice blast and the rice sheath blight (SB) are the two most devastating diseases affecting the productivity of rice in Sri Lanka. Rice blast, caused by Magnaporthe oryzae, could result in loss of about one million hectares of paddy in Asia annually, depending on the varieties grown. The disease SB caused by Rhizoctonia solani Kuhn is another destructive rice disease worldwide, and it can lead to severe losses in rice productivity. It is noted that some of the Sri Lankan rice varieties have lost their blast resistance after few years of cultivation. Therefore, improving disease resistance in rice is crucial for stable rice production.

Almost 100 blast resistance genes have been identified worldwide. All these genes have been mapped on all rice chromosomes except for chromosome 3. Rice cultivar ‘Tetep’ is one of the sources of resistance genes. It is a donor of blast resistance genes, Pita, Pi1(t), Pi4a(t), Pi4b(t), Pi3(t), Pi-tp(t), and Pi54. Among these, Pi54 is a major dominant gene. Major genes for blast resistance Pi-1(t) and Pi 54 have been mapped on chromosome 11 and Pi-tp (t) on chromosome 1. SSR marker RM 206, is tightly linked to the Pi54 gene and it produces DNA fragment of 130 bp in Tetep. The cultivar ‘Tetep’ also possesses a major QTL for SB resistance, qSBR11-1, on the arm of chromosome 11, in which Pi54 is also located. The SSR marker RM 224 is flanking the SB resistance QTL qSBR11-1.

‘Pokuru Samba’ is a high yielding popular rice cultivar in Sri Lanka but not recommended as a rice variety due to its susceptibility to blast disease. The objective of this study was to develop marker-assisted selection in backcross breeding programmes for improving disease resistance in popular rice varieties. In this study, the cultivar ‘Tetep’ was used as donor for incorporating the blast resistance gene, Pi54 and sheath blight resistant QTL qSBR11-1 into local susceptible cultivar Pokuru Samba , through marker-assisted foreground selection in combination with fungal inoculation and

MOLECULAR BREEDING FOR BLAST & SHEATH BLIGHT RESISTANCE FOR RICE 97 selection for blast disease in the blast screening nursery, followed by phenotypic selection for recovery of agronomic, morphological traits.

The recurrent parent, Pokuru samba was hybridized with ‘Tetep the donor for the blast and SB resistance gene Pi54 and qSBR11-1 QTL, respectively. BC 2F1seeds were obtained by back crossing the BC 1F1 with recurrent parent Pokuru Samba. All the seeds were planted in trays and inoculated with Pyricularia oryzae in the blast screening nursery at Rice Research and Development Institute, Bathalagoda in the 2014/15 Maha cropping season in comparison with blast susceptible traditional rice cultivar ‘Puchchaperumal’. Plants were selected when the blast disease was developed and susceptible cultivar ‘Pachchaperumal’ died completely. At that stage, all the plants in backcrossed population were scored using the standard scoring system developed in International Rice Research Institute. Plants which did not show any blast symptom and scored ‘Resistant’ category were subjected to molecular marker assisted foreground selection.

Total DNA was extracted from leaf samples by using the KCl DNA extraction protocol. The PCR reactions were carried out with in a final volume of 15 pl containing,

3 pl of DNA sample, 3.0 pl 5x PCR buffers with 0.9 pl MgCl 2 (25 mM), 0.15pl of 10 mM dNTP (Promega, U.S.A.), 1.0 pl of primer (RM 206 and RM 224 at the concentration of 20 pM), and 0.075 pl of 5 u/pl Taq DNA polymerase (Promega, U.S.A.) in a thermal profile of initial denaturation (5 minutes at 95 0C) followed by 35 cycles of denaturation (at 95 0C for 1 minute), Primer annealing (55 0C for 30 seconds), extension (at 72 0C for 1 minute) and final extension at 72 0C for 2 min. Two simple sequence repeat markers used in previous studies, RM 206 and RM 224 for gene Pi54 and qSBR11-1 QTL, respectively were selected for PCR amplification. The PCR amplicons were visualized in 2% agarose gel. Heterozygous plants for both markers were further selected for recovery of recurrent parent phenotype and used for developing BC 3FI. Similarly, the plants of BC 3FI population were selected following the same procedure.

Seventy two plants of BC 2F1 population were screened for blast resistance at the blast screening nursery at RRDI. A total of 27 plants were grouped in ‘Resistant’ category and were subjected to genotypic screening. In BC 3F1 population, 66 plants were screened, and 12 plants were included in ‘Resistant’ category. Out of 27 plants, six plants carried RM 206 (130bp) molecular maker which is tightly linked to Pi54 gene. Marker- assisted selection for SB showed 21 plants with heterozygous molecular band for flanking marker for SB QTL, qSBR11-1, RM 224. Out of five plants selected as pyramided lines of both Pi54 and qSBR11- genotypes only 2 plants were selected from

98 KEKULANDARA et al.

BC 2FI for recurrent parent phenotypic recovery. Similarly, out of 66 plants in BC 3F1 population 2 gene pyramided plants were selected. Instead of marker aided background selection, phenotypic selection was the method used to have maximum recovery of recurrent phenotypes such as plant height, grain shape, and number of panicles, because use of large number of molecular markers for back ground selection is a costly, laborious and labour consuming task although it is more accurate and reliable.

This study proved that marker assisted back cross breeding approach can be successfully used for introgression of one or more genes into a desired rice variety. It accelerates the improvement of rice varieties with disease resistance. The breeding lines selected in this study will be an important source for developing disease resistant rice varieties. The breeding approach used would be guidance for application of MABB in developing disease resistant varieties with higher reliability and accuracy.

REFERENCES

Channamallikarjuna, V., H. Sonah, M. Prasad , G.J.N. Rao, S. Chand, H.C. Upreti, N.K. Singh and T.R. Sharma . 2010. Identification of major quantitative trait loci qSBR11-1 for sheath blight resistance in rice. Molecular Breeding, 25: 155-166. Fjellstrom, R., C. Bormans, C.A.; McClung, A.M., Marchetti, M.A.; Shank, A.R. Park, W.D. Park. 2004. Development of DNA markers suitable for marker assisted selection of three Pi genes conferring resistance to multiple Pyricularia grisea pathotypes. Crop Sci. 44: 1790-1798. Sharma, T.R.,M.S. Madhav, B.K. Singh, P. Shanker, T.K. Jana, V. Dalal, A. Pandit, A.Singh, K. Gaikwad, H.C. Upret. and N.K. Singh. 2005. High resolution mapping, cloning and molecular characterization of the Pikh gene of rice, which confers resistance to M. grisea. Mol. Genet. & Genomics. 274: 569-578.

Annals of Sri Lanka Department ofAgriculture 2016. 18: 99 - 101

ANKCP 01: A NEW COWPEA (VIGNA UNGICULATA (L.) WALP.) VARIETY FOR CULTIVATION IN DRY AND INTERMEDIATE ZONES OF SRI LANKA

B.N. SAMARANAYAKE, M.C. MILLAWITHANACHCHI, N.T. PRATHAPASINGHE, AND R.A.A. RANATHUNGA

Grain Legumes and Oil Crops Research and Development Centre, Angunakolapellassa, Sri Lanka

EXTENDED ABSTRACT

Cowpea is one of the main grain legumes of the cropping systems in the drier regions of Sri Lanka. While providing a good protein source, being a fast growing crop, cowpea reduces erosion by covering the ground, fixes atmospheric nitrogen and subsequently contributes for the soil fertility. Among the conventional cowpea growing farmers popularity of recommended varieties was at considerably low level and most of the famers used to grow their own collection of varieties (Hewavitharana et al., 2010). Hence development of farmer preferred varieties with better adaptability would fulfil the actual needs of the farmers in the rain-fed area of Sri Lanka. Cowpea improvement program of Grain Legumes and Oil crops Research and Development Center (GLORDC), Angunakolapellassa targeted to develop high yielding cowpea varieties with better adaptability and consumer preferred characteristics.

Seven crosses were made using MI35, Waruni, Dhawala and MICH 01 varieties at GLORDC, Angunakolapellassa during 2006/2007 Maha and F1 populations were advanced during 2007 Yala. F2 to F5 generation advancements were conducted using pedigree method from 2007/08 Maha to 2009 Yala. From the advanced breeding lines of the tested crosses four lines were selected and evaluated in Preliminary yield trial (PYT) and Major yield trials (MYT) with stranded check varieties in Randomized complete block design (RCBD) during 2010/11 Maha and 2011 Yala. The plot size was 4 m x 2.4 m and with 30 x 15 cm spacing between and within rows. Better performing lines further evaluated in National Coordinated Varietal test (NCVT) trials during 2011/12 Maha and 2012 Yala and consist with seven entries and three stranded checks in RCBD with three replicates in 4m x 2.4m plots with 30 x 15 cm spacing.

Agronomic characters were recorded along with the plot yields. NCVT testing locations were at Aralaganvila, Agunakolapalessa, Makandura, Mahaiuppallama, Kilinochchi, Vavniya and Maduraketiya. The best performers were selected for varietal adaptability test (VAT) in farmer fields at Aralaganvila, Hambantota, Kilinochchi, Vavniya, Moneragala during 2013 Yala and 2013/14 Maha and the best out of VAT were tested in Large Scale VAT at Anuradapura, Batticaloa, and Hambanthota during

100 SAMARANAYAKE et al.

2014 Yala. Sensory evaluation was conducted using the best variety selected ANKCP 01 and the recommended varieties Waruni, Dhawala and MICP1. Yield trials at research station were analyzed using analysis of variance and followed by mean separation with Lease Significant Difference using SAS. Multi-location yield data of NCVT were analyzed using both ranking method (Das, 1982) and variance component method (Abeysiriwardena, 1991). VAT data were analyzed using ranking method.

There was no significant difference (p<0.05) among tested lines for yield during 2010/11 Maha evaluations in PYT. There was a significant difference (p<0.05) among tested lines during 2011 Yala evaluations and the highest yield recorder was ANKCP01 during both seasons. According to NCVT data analysis with ranking method, considering the highest mean rank and lowest variance of ranks of adaptability rank 01 was given to Waruni, ANKCH 11 received rank 2 and ANKCP01 received the rank 03 for the 2011/12 Maha season analysis. ANKCP01 received rank 1, ANCFC ranked as 2 and Waruni received rank 3 for ranking method during 2012 Yala season data analysis.

Results of variance component method analysis with respect to 2011/12 Maha and 2012 Yala based on number of positive deviations, mean deviations over locations and interaction variance ANCH 11 received rank 1 and ANCFC 17 received rank 2 during 2011/12 Maha season and for the 2012 Yala season evaluations ANCFC 17 received rank 1 and ANKCP01 received rank 2. According to individual location analysis of variance Hambantota farmer field yields were significantly different for 2013 Yala evaluations and the other locations were not significant. According to analysis of variance yields of Vavniya, Aralaganvila and Anngunakolapellesa were significantly different during 2013/14 yala. ANKCP01 received rank 1 for both seasons with better yield performance. ANKCP01 recorded over 1,200 kg/ha yield in two locations out of tested three during 2013 Yala. The same variety received 1,200 kg/ha of yield in three locations out of 5 during 2013/14 Maha .

Analysis of variance of days to flowering was significantly different and there were two distinguish groups which showed early flowering with 42-44 days and late flowering with more than 50 days, ANKCP 01 belongs to early flowering group along with the Waruni, Dhawala and MI 35. For the maturity characteristic also ANKCP 01 showed resemble results with the early maturing varieties Waruni, Dhawala and MI 35. The variety exhibited a determinate growth habit with moderate number of pod per plant

NEW COWPEA VARIETY FOR CULTIVATION IN SRI LANKA 101 compared to recommended check varieties. The variety ANKCP 01 has 14 seed per pod and the hundred seed weight also higher compared to Waruni.

Sensory attributes such as colour, texture, taste and aroma were significantly different among the varieties. Seed colour and taste were significantly (p<0.05) higher in ANKCP 01. There were no significant (p<0.05) different for texture and aroma for tested varieties. However, ANKCP 01 was the most preferred boiled cowpea variety among the tested samples while MICP 01 was the second place. In addition, majority (70 %) of the farmers who involved in the VAT and LSVAT preferred ANKCP 01than the other check varieties, due to the superior plant structure and seed characters (seed size, shape and the attractive seed coat color). The capability of providing 70% of the harvest from the first picks also one of the reasons for higher preference of the new variety among the farmers.

ANKCP 01 is capable of providing more than 1,200 kg/ha in both Yala and Maha seasons. Further the new variety provides 70% of grain harvest at 1 st pick and matured within 64 days. The new variety was preferred by farmers due to high seed quality, cooking qualities and the taste. Therefore, the tested new variety was released as ANKCP 01 for the cultivation of cowpea growing areas of Sri Lanka in 2014.

REFERENCES

Abeysiriwardena, D.S.D.Z. 1991. Analysis of multi-environmental yield trials for testing adaptability of crop genotypes. Tropical Agriculturist. 147: 85-97. Das, G.R. 1982. A method of scoring yield status for selecting rice cultivars. Indian J. Agric. Sci. 52 (4): 207-209. Hewavitharane. H.V.C., H.U. Warnakualsooriya and G.B.S .Wajirakumara. 2010. Constraints to expansion of cowpea and mungbean under rain-fed farming in Anuradapuara district .Annals of the Sri Lanka Department of Agriculture. 12: 91-105

Annals of Sri Lanka Department of Agriculture 2016. 18: 102 - 110

EFFECT OF SOIL CONSERVATION MEASURES ON SOIL EROSION, SOIL MOISTURE AND CROP PRODUCTIVITY IN THE MID COUNTRY INTERMEDIATE ZONE OF SRI LANKA

A.G. CHANDRAPALA, K.M.A. KENDARAGAMA and T.M.N.D.

KUMARIHAMY

Natural Resources Management Centre, Peradeniya, Sri Lanka

EXTENDED ABSTRACT Randenigala is one of the largest reservoirs in Sri Lanka constructed in year 1984 under Accelerated Mahaweli Development Program with a catchment area of 2330km 2. Considering the importance of the catchment area of Randenigala reservoir to the national economy and environment, Environment Action 1 Project (EA1P) introduced on-farm and off-farm soil conservation measures within the area in year 2001. Present study was conducted in Heelpankandura sub catchment of Randenigala reservoir catchment in the mid country intermediate zone of Sri Lanka to evaluate the effectiveness of introduced vegetative and mechanical on farm soil conservation measures, in terms of soil erosion, soil moisture conservation and growth and yield of brinjal (Solanum melongena Linn. ) as there is very little information available on comparison of mechanical and vegetative soil conservation measures on soil erosion, crop productivity and soil moisture conservation in Sri Lanka.

The research was conducted in 2001-2002 Maha season in two farmer fields in Udawatta village, Randenigala reservoir catchment (IM 3c agro-ecological region). The area is having a uni-modal rainfall pattern with average annual rainfall of about 1250 - 3000mm. Soil of the area is Reddish Brown Latasolic in a steeply dissected rolling and hilly terrain (Panabokke, 1996). Three soil conservation measures (stone bunds, Gliricidia double hedgerows and Finger millet strip crop) were compared with sole crop control in Randomized Complete Block design with six replicates in (30% slope) two farmer fields. Stone bunds (45cm height, 60cm width) and Gliricidia double hedgerows (between row 50cm, within row 15cm) were already established in 12m interval along the transect, 6 months before the experiment by the Environment Action 1 (EA1P) Project. Finger millet ( Eleusine coracana ) seeds were sown densely (seed rate, 16 kg/ha) in 12 meter interval as 0.5m wide band along the contour at the time of land preparation as a strip crop.

Twenty five days old seedlings of brinjal (cv. SM 164) were planted in 60 x 90 cm spacing along the contours in each plot and the crop was raised as a rain-fed crop.

EFFECT OF SOIL CONSERVATION ON SOIL EROSION AND CROP YIRLD 103

Fertilizer application and all the other crop management practices were adopted according to the recommendation of the Department of Agriculture (DOA, 1990). Soil erosion was measured using erosion plots made with 22.1m x 4m dimensions and gravimetric soil moisture content was measured using weight difference of wet soil and oven dry soil was divided by oven dry weight of soil. Bulk density of the soil was measured using core sampler and determined by dividing the weight of the oven dry soil by inner volume of the core. Average height of plants in each row was measured at 50% flowering and pods per plant were measured in each row by counting all the pods in each row at the time of harvesting.

According to the results, rainfall received during one month period of land preparation was 555.2 mm with 2 high intensity rainfall events of 99.5 mm/day and 111.5 mm/day. However, during the four months period of crop growth, received rainfall was only 685.4 mm with three moderate intensity rainfall events of 58.6 mm/day, 67.5 mm/day and 76 mm/day. Among the treatments, significantly highest soil erosion during both land preparation and crop growing period was recorded by the treatment of sole brinjal cropping. However, it was on par with strip cropping treatment in land preparation period. Stone bund treatment recorded the lowest soil erosion in both land preparation ( 66 % reduction) and crop growing period ( 86 % reduction, but on par with gliricidia double hedgerow treatment in crop growing period. Anyhow, compared to 4 months crop growing period of brinjal, one month land preparation period recorded over 80% of soil erosion regardless of the treatment.

Significantly highest brinjal pod yield was observed under stone bund treatment and rest of the treatments recorded on par crop yield values, but significantly lower than stone bund treatment. gliricidia double hedgerow treatment recorded the statistically similar crop yields as sole cropping and strip cropping treatments. Significant difference of gravimetric soil moisture content among treatments or between middle (6 m from lower end) and lower (1 m from lower end) parts of the plot was not observed at one month after planting of brinjal. However, significantly highest nd gravimetric soil moisture content was observed in stone bund treatment at both 2 and rd 3 months after planting. Significant difference of soil moisture content was not observed under the treatments of strip cropping, gliricidia double hedgerows and sole brinjal cropping at 2 months after planting. However, significant reduction of gravimetric soil moisture content at 3 months after planting was observed in the treatment of gliricidia double hedgerows. The effect became more apparent at the end of rd rd 3 month, because there was a one and half month dry spell before 3 sampling.

104 CHANDRAPALA et al.

In position-wise comparison, highest gravimetric soil moisture content was observed in lower position ( 1m from lower stone bund) of the stone bund treatment nd rd compared to middle part of the plot (6 m from lower stone bund) at 2 and 3 months after planting. At 3 rd month after planting, position wise difference of soil moisture was also observed under gliricidia double hedgerow treatment. However, in contrast to the stone bund treatment, highest soil moisture availability was observed in the middle part of the plot in hedgerow intercropping treatment.

Treatment-wise significant variation of bulk density of soil was not observed at the end of 1 st , 2 nd or 3rd months after planting of brinjal. However, significant reduction of bulk density of soil was observed in lower position of stone bund treatment at 3 months after planting of brinjal compared to middle part of the plot. Increasing trend of plant height and pods/plant from upper stone bund to lower stone bund was observed in row wise comparison of plant height and pods per plant. However, prominent row-wise variation of plant height or pods/plant of brinjal from upper strip crop layer to lower strip crop layer was not observed in strip cropping treatment. In the gliricidia double hedgerow intercropping treatment, variation of row-wise brinjal plant height and pods/plant across a transect of the ally between two adjacent gliricidia double hedgerows showed that brinjal plant heights and pods/plant were reduced in rows closer to the hedgerows on both sides. Row-wise plant heights and pods/plant had a single peak in the middle of the plot in gliricidia double hedgerow treatment across transect. However, sole crop row-wise plant height and pods per plant showed linear pattern of variation across transect.

Based on the results, it was concluded that the use of stone bunds for soil conservation in mid country intermediate zone is more appropriate compared to gliricidia double hedgerows and finger millet strip cropping. In addition to soil conservation, stone bund increases the crop (brinjal) yield and soil moisture availability to crop plants. gliricidia double hedgerows exert considerable competition to associate intercrop, when they are planted closer to the hedgerows.

REFERENCES

Department of Agriculture., (1990). Crop Recommendations Techno Guide. Department of Agriculture, Peradeniya, Sri Lanka. p. 46 Gamage, H. (1997). Land Use in Sri Lanka, Economic Policy Reforms and the Environment: Land Degradation in Sri Lanka, Ministry of Public Administration, Home Affairs and Plantation Industries, 17 -75. Panabokke, C.R. (1996). Soils and Agro ecological environment of Sri Lanka. Natural Resources Energy and Science Authority, Colombo, Sri Lanka, p. 200.

Annals of Sri Lanka Department of Agriculture 2016. 18: 105 - 110

EFFECT OF DRY HEAT TREATMENT ON PHYSICOCHEMICAL PARAMETERS OF COIR AND ERADICATION OF FUSARIUM SOLANI

M.H.A.D. SUBHASHINI 1, C. GAMAGE 2 AND K.S.I. SENAVIRATHNA 1

1 National Plant Quarantine Service, Canada Friendship Road, Katunayake, Sri Lanka 2 Department of Agricultural and Plantation Engineering, Faculty of Engineering Technology, Open University, Colombo, Sri Lanka

EXTENDED ABSTRACT

Sri Lanka exports coir and coir products that have a constant share in the economy of the country. Sri-Lanka is the largest brown fibre exporter to the world, annual export is more than 100,000mt (Subhashini et al., 2015). The physical and chemical properties of coco peat from numerous sources have been found to be within acceptable ranges and suitable for use as a growth medium (Asiah et al., 2004). The pH, electrical conductivity (EC), bulk density (BD), water holding capacity(WHC), porosity and expandability(EP) are the important physicochemical properties of coir for it to be considered as a growing medium. In the past, coir exported to foreign countries from Sri Lanka has been reported to have contaminated with fungal pathogen Fusarium solani, which is a phytopathogenic fungus and is an important causal agent of several crop diseases such as root and fruit rot of Cucurbita spp., root and stem rot of pea, sudden death syndrome of soybean, foot rot of bean and dry rot of potato (Luginbuhl, 2010) despite the fact that those consignments were exported with a normal Phytosanitary Certificate. Hence, this study was carried out to select the best combination of heating temperature and exposure time to eradicate F. solani in coir while maintaining physicochemical properties required for plant growth.

Coir dust used for the experiment was sterilized by solarising in the premises of National Plant Quarantine Service (NPQS) at Katunayake in Sri Lanka to eradicate pathogen-contamination. Solarized coir was analyzed using the standard pathological tests to ensure that no pathogenic contaminations are present before imposing heat treatments. The solarized coir was cultured on potato dextrose agar by adopting dilution plate of Aneja (2003) method and cultures were examined under microscope after 5 days. Standard spore suspension (10 4 spores/ml) was prepared using pure culture of F. solani for the inoculation of solarized coir. Then the coir was checked for the presence of the pathogen after five days. Initial concentration of all replicates was maintained at the same inoculum level to assess the treatment effect accurately. These trays were kept in air circulating ovens preset with time and temperature. The experiment was arranged in a two factor factorial experiment with three replicates and the results were analyzed using the SAS computer software (SAS, 2004). Temperature (50 °C, 55 °C, 60 °C and 65 °C) and time (0 hour, 1 hour, 2 hours and 3 hours) were the two factors. Cluster

106 SUBASHINI et al. analysis for spore count and physicochemical properties were performed as well using MINITAB 17. The sample kept at the room temperature (around 32 °C) served as the control.

Samples collected from each treatment were cultured separately by adopting the dilution plate method described by Aneja (2003) to obtain spore counts and measure physiochemical properties. The physiochemical properties measured were the pH, electrical conductivity (mS/cm),bulk density(g/cm -3), porosity (%), water holding capacity (% by volume), and expansion power (% by volume) using standard methods. Spore count (SC) reduced significantly (p<0.05) with time and temperature. The initial SC in treated and the control kept at room temperature did not show significant difference (p>0.05).When heat-treated at 50 °C for 1 hour and 2 hours, the SC remained unchanged compared to the control while 3hour exposure made a complete destruction of F.solani spores. The SC became zero after 1h exposure to temperature 55 °C and above.

Physicochemical properties of coir were affected by temperature and the duration of exposure to the temperature as well. Porosity of the material reduced with both increasing temperatures and time. Porosityof coir heat-treated at 55 °C for 1 hour was lower than that at 50 °C for 1 hour. However, no significant difference (p>0.05) was observed in porosity between heating at 50 °C and 55 °C for 1 hour. There was no reduction in WHC when the material was exposed to 50 °C and 55 °C. However, the WHC decreased at 60 °C and 65 °C and did not show any effect with time. Expansion power and EC were reduced at high temperatures (e.g. 65 °C) but there was no significant effect with time (p>0.05). Both Bulk Density and pH remained unchanged with increasing temperature and time. Changes showed were not significant at 5% probability. In cluster analysis, it also revealed that (BD) and pH were grouped together due to no change observed after treatment whereas the WHC formed a single cluster and separated from (EP), porosity and EC due to slight change occurred with treatment compare to the three properties mentioned above.Treatments,55 oC for 1 hour and 55 oC for 2 hours grouped together and separated from treatment 50°C for 3 hours due to the effect of both temperature and time combination showed lower impact on the physicochemical properties apart from the absence of spores. Meanwhile, the temperatures above 55 0C changed physico-chemical properties even the absence of spores. Accordingly, heat treatment at 55 °C for 1 hour is more economical than heating at 55 °C for 2 hours.

EFFECT OF HEAT TREATMENT ON QUALITY OF COIR AND ERADICATION OF FUSARIUM SOLANI 107

In the past, the presence of some pathogens like F. solani and Rhizoctonia solani with export coir was reported by some countries. Therefore, they made the heat treatment as a prerequisite for their products. Hence, exporting countries like Sri Lanka are bound to fulfil the requirements of the importing countries irrespective of the cost concerned. The study concluded that heat treatment at 55 °C for 1 hour is the best among treatment combinations evaluated to eradicate F. solanii n coir products while maintaining physicochemical property standards required for plant growth.

REFERENCES

Aneja, K.R., 2003. Experiments in Microbiology Plant Pathology and Biotechnology. 4 th edition, New Age International Publishers. Pp 147-156. Asiah A., R.I. Mohd, Y.K.Mohd., M. Marziah and M. Shaharuddin. 2004. Physical and Chemical Properties of Coconut Coir Dust and Oil Palm Empty Fruit Bunch and the Growth of Hybrid Heat Tolerant Cauliflower Plant. Trop. Agric. Sci. 27(2): 121-133. Luginbuhl, S. 2010. Fusarium solani a class project for PP728 Soil borne Plant Pathogens. NC State University. Available at: https://projects.ncsu.edu Subhashini, M.H.A.D. and A.A.S Yasodara. 2015. Effect of solarization for eliminating Thielaviopsis paradoxa from export coir products. Annals of Sri Lanka Department of Agricuture. 17:340-345.

Annals of Sri Lanka Department of Agriculture 2016. 18: 108 - 110

PERFORMANCE AND ADAPTABILITY OF NEW YARD-LONG BEAN VARIETY: GANNORUWA A9 MAE

P. MALATHY, W.D.G.P. NILANTHI, E.M.N.T.M. EKANAYAKE,

W.A.R.T. WICKRAMAARACHCHI AND K.H. SARANANDA

Horticultural Crops Research & Development Institute, Gannoruwa, Sri Lanka

EXTENDED ABSTRACT Production and marketing of Yard- long bean are hindered by low yield, collar rot disease and poor shelf life of pods. Hence, a program was initiated with the objective of developing high yielding, collar rot disease resistant/tolerant varieties having good quality characteristics for commercial cultivation using local and exotic germplasm. This study was aimed to evaluate improved lines for yield, quality, adaptability and disease resistance to identify a suitable Yard-long bean variety for Sri Lankan farmers. Performance of locally developed Yard-long bean lines was studied for seven consecutive seasons from Yala 2010 to 2014 Yala. Seven improved lines, 39-1, 39-2, 39 8, 39-9, 39-11, 39-12 and 39-13 were evaluated along with the recommended check varieties Hawari and Polon for yield and yield attributes in replicated trials from 2010 to 2011 at the Horticultural Crops Research and Development Institute. Records on number of pods and yield per plant were taken from six randomly selected plants while pod length, circumference and weight were obtained from ten fresh pods randomly selected from each plot. Data were analyzed using ANOVA procedure.

Stability and adaptability of five selected lines were evaluated at six research centres and forty five farmer locations representing major agro ecological regions from Maha 2011/12 to Yala 2014.Stability of varieties was analyzed using plot deviation of yield from the environment mean while adaptability was assessed by analyzing yield data using plot deviation of each variety from the best plot yield in each location (Abeysiriwardena et al., 1991). Two promising lines, 39-9 and 39-12, selected based on the performance in stability studies during Maha 2011/12, were evaluated along with the recommended varieties Polon and Hawari under field conditions of natural inoculation during both 2012 Yala (dry season) and 2013/ 2014 Maha (wet season). Wilted plants due to the infection of collar and root rot disease were recorded during each season. Percent disease incidence for each variety was statistically analyzed.

Quality characteristics of 39-9 and 39-12 were evaluated at the Food Research Unit, Gannoruwa. Acceptability of the varieties was assessed by32 randomly selected

PERFORMANCE AND ADAPTABILITY OF NEW YARD-LONG BEAN VARIETY 109 individuals. Friedman test was used to analyze the data. The shelf life of the most promising variety, 39-9 was evaluated under ambient and refrigerator conditions in the dry zone. Results revealed that length of pods, pod circumference and single pod weight varied significantly among the tested lines. Significant differences in number of pods/plant were observed among different lines and seasons. Single plant yield varied significantly among the lines and seasons, yet line 39-9 showed no significant seasonal effect. Line 39- 9 gave the highest pod number (40) and single plant yield (731.8g). The pod length, pod weight and number of pods/plant were reported as important yield attributing factors in vegetable cowpea (Kar et al, 1995; Hazral et al., 2007; Nwofia, 2012; Pek§en and Pek§en, 2012). In this study, all the lines test produced high yields and lengthy pods. However, lines 39-8 and 39-11 showed segregation even after F 6 generation. Hence, lines 39-1, 39-2, 39-9, 39-12 and 39-13 were selected for adaptability studies.

Results obtained in the stability study showed significant yield variation among varieties. The best performing genotypes with regard to yield were 39-12 and 39-9 while variety, Hawari produced low yield. In addition, lines 39-12 and 39-9 expressed high positive mean deviation and non-significant stability parameters, hence both lines can be considered as stable. In the adaptability study, there was no Genotype x Environment interaction observed across the tested agro ecological regions during both Yala and Maha seasons. Moreover, lines 39-9 and 39-12 showed the least mean deviation and nonsignificant stability parameters, hence they can be considered as widely adaptable varieties.

In general, more disease incidence was observed during Maha (wet season) compared to the Yala (dry season) irrespective of varieties. Both recommend varieties showed higher susceptibility to root rot disease compared to newly develop promising lines. Line 39-9 showed the highest level of field resistance (2.13 and 4.26 percent disease incidence respectively) during Yala and Maha. The line, 39-9 scored the highest median values for appearance and taste followed by line 39-12. Further, pods of line 39-9 took longer time for colour change and to shrink under both ambient temperature and refrigerated conditions compared to the variety Hawari. These results revealed that the line 39-9 was preferred for better quality characteristics by the users. Green colour and long fleshy pods make marketing of line 39-9 easy. Farmers preferred line 39-9 owing to pod characters and whereas consumers preferred it due to pod colour, taste and keeping quality.

110 MALATHY et al.

Yard- long bean line39-9, produced high yield (20.3-25.3 t/ha), showed field resistance to collar rot disease, high adaptability and produced long fleshy green pods with greater shelf-life. Hence, line 39-9 was released as “Gannoruwa A9 Mae ” for island wide cultivation.

ACKNOWLEDGEMENT

Authors wish to thank the researchers and extension personnel for their support extended during this study period. The financial assistance provided by Sri Lanka Council for Agriculture Research Policy to conduct this study is highly acknowledged.

REFERENCES

Abeysiriwardena, D.S. de Ze., G.R. Buss and P.E. Reese Jr. 1991. Analysis of multi environmental yield trials for testing adaptability of crop genotypes. Tropical Agriculturist 147:85- 97. Hazra, P., A. Chattopadhaya, T. Dasgupta, N. Kar, P.K. Das and M.G. Som. 2007. Breeding Strategy for Improving Plant Type, Pod Yield and Protein content in Vegetable Cowpea (Vigna unguiculata). Acta Horticulture 752: 275 - 280 Kar, N., T. Dasgupta, P. Hazra and M.G. Som. 1995. Association of pod yield and its components in vegetable cowpea. Indian Agriculturist 39: 231- 238. Nwofia, G.E. 2012. Yield and yield components in vegetable cowpea on an ultisol. African Journal of Agricultural Research Vol. 7(28), pp. 4097-4103. Pek§en, E and A. Pek§en. 2012. Evaluation of Vegetable Cowpea (Vigna unguiculata (L.) Walp.) Breeding Lines for Cultivar Development. Igdir Univ. J. Inst. Sci. & Tech. 2(4): 9-18.

Annals of Sri Lanka Department of Agriculture 2016. 18: 111 - 114

MANAGEMENT CHILLI VEINAL MOTTLE VIRUS IN CHILLI USING PSEUDONOMAS FLOURESCENCE

C. RANASINGHE \ P.M. MALLIKAARACHCHI 2, D.M. GUNASEKERA 1 AND V. NAVAGAMUWA 1

1 Plant Virus Indexing Center, Homagama, Sri Lanka 2 Faculty of Agriculture, University of Ruhuna, Matara, Sri Lanka

EXTENDED ABSTRACT

Chilli is an important and essential component of daily Sri Lankan diet. This crop is susceptible to wide range of virus diseases which resulting for heavy crop losses. Among these, Chilli Veinal Mottle Virus (ChiVMV) is one of the major prevalent virus (Anon, 2001). Viruses differ from other plant pathogens and pests because they cannot be eradicated chemically. Utilization of beneficial microbes isolated from rhizosphere, referred to as Plant Growth Promoting Rhizobacteria (PGPR), might offer a promising viral disease control strategy. Pseudomonas fluorescence, a PGPR, commonly used as bio control agents, is reported to apply against several viral diseases (Maurhoper et al, 1994; Elbadry et al., 2006; Rakib et al., 2012). However, no detail studies have been conducted on the application of P. florescence against ChiVMV in chilli in Sri Lanka. This study was conducted to evaluate the effectiveness of P. fluorescence against ChiVMV in chilli. Specific objectives are the isolation of P. fluorescence from chilli rhizosphere, identification and confirmation of isolates as P. fluorescence, and testing the efficacy of P. fluorescence in inducing resistance in chilli against ChiVMV.

Rhizosphere soil adhered to the roots of the healthy chilli plants were collected from the chilli cultivations located at Mahailluppallam, Hambanthoa, Matale and Athurigiriya areas. Bacteria were isolated from the rhizosphere soil by dilution plate count technique on King’s B (KB) media (King et al., 1954). Bacterial colonies grown on KB medium were observed under Ultra Violet (UV) light and fluorescent colonies were isolated. All isolated colonies were then subjected to biochemical assays (Gram reaction, catalase test, semi solid medium test, starch hydrolysis test, methyl red vogas proskauer (MRVP) test) according to Bergey’s Manual for Determinative Bacteriology (Breed et al, 1989).

Efficacy of the isolates of P. fluorescence was separately tested by seed treatment and soil drench method. In seed treatment, chilli seeds (variety MI-2) were soaked for 18 hrs in each bacterial suspension namely, M1, M2, ATC2, MTC3, and H4, separately and in soil drench method, one month old chilli plants of variety MI-2 were dipped in each bacterial suspension. Seeds and plants treated with water was used as a control. In both

112 RANASINGHE et al. method bacterial concentration 1x10 8 cfu/ml was used. Five weeks old treated plants were mechanically inoculated with ChiVMV infected sap (1:10w/v) in phosphate buffer pH 7.0. Each isolate (treatment) was replicated four (three plant/replicate) times and the plants were arranged according to the complete randomized design.

To examine the effect of isolates of P. fluorescence, plant height, fresh and dry weights of the shoots and roots were measured at the end of the experiment. Disease severity rating was made from one week to eight week after post inoculation by using the following rating scale on the leaves. 0- No symptoms, 1- <10 % canopy infection, 2-1125 % canopy infection, 3- 26-50 % of canopy infection, 4- 51-75 % canopy infection, 5- >75 % canopy infection. Accumulation of ChiVMV in foliar tissues was determined by double antibody sandwich Enzyme Linked Immunosorbance Assey (DAS-ELISA) using commercially available antiserum for ChiVMV. For each experiment, disease severity was measured by the area under disease progress curve (AUDPC). Data were analyzed using analysis of variance (ANOVA) in SAS. Means were compared using Least Significant Different (LSD).

A total of 25 soil samples were collected and 5 isolates were identified as P. fluorescence using culture characters on KB and biochemical tests. There was a significant difference (P=0.0001) among all five isolates compared with the control in both application methods. All isolates in both application methods showed lesser disease severity compared to untreated plants. Furthermore, isolate M2 showed the least disease severity in both application methods. Similar results were demonstrated by Damayanti and Katerina (2008) in which rhizobacteria treatment on hot pepper inoculated with tobacco mosaic virus (TMV) and chilli veinal mottle virus (ChiVMV) exhibited milder symptom expression compared with control plants. There was a positive correlation of disease severity with time in all isolates in both application methods. In seed treatment method, isolates MTC3, ATC2 and M2 showed less disease severity with time while in soil drench method, isolates MTC3 and M2 only showed less disease severity with time compared to untreated plants.

All five tested bacterial isolates showed their ability to enhance plant growth in both methods. There was no significant difference (0.17) between the two application methods with respect to plant height. However, there was a significant difference among the treatments (0.0001). Furthermore, there was an interaction between the application methods and treatments for plant height (0.0001). In seed treatment method, there was no

MANAGEMENT CHILLI VEINAL MOTTLE VIRUS USING PSEUDONOMAS FLOURESCENCE 113 significant difference in plant height compared to the control. However, a significant difference in plant height compared to the control was observed in the soil drench method. This result indicates that application of P. flourescence as a soil drench has increased the plant height.

The fresh weights of the roots were significantly different (0.0156) between two methods of application as well as among the treatments (0.0209). Further, Root fresh weight is higher in seed treated plants than the plants of soil drench method. There is an interaction between application methods and treatments (P=0.035). In seed treatment method, root fresh weights were higher in all the isolates than that in untreated plants. However, in soil drench method, there was no significant difference among treatments. This clearly indicates that seed treated with P. flourescence has increased the root growth.

When consider shoot fresh and dry weights, there was a significant difference between the two application methods and among the treatments. But root dry weight differed among treatments. There is no interaction between the application methods and treatments in above three growth parameters. Shoot fresh weight was higher in ATC2, M1 and M 2 isolates than that in control. Comparatively, shoot dry weight was high in the isolates; ATC 2 and M 1. When consider root dry weight, it was high in the isolates ATC 2, M1, M2 and H4 compared to control. This is in agreement with the results of Parmer and Dadarwal (1999), where PGPR treatment of groundnut plants increased the dry weight of root significantly.

There is a significant difference (P=0.02) in virus concentrations between the two application methods and between treatments (P=0.0066) based on DAS-ELISA test results. Seed treated plants showed lesser virus than soil drench plants. Furthermore, there is no interaction between the treatments and application methods (0.189). the mean ELISA absorbance values of the plants treated with bacterial isolates MTC3, ATC2 and M2 showed negative reaction to the ELISA test as well as low virus titer compared to the untreated plants. These results showed that treating plants with P.fluorescence enhanced the plant growth while reducing virus titer. Furthermore, some of the bacterial treatments could maintain better plant growth characters than the control plants, even when they were infected by ChiVMV. These results were in agreement with Damayanthi et al . (2007) which evaluated the application of root colonizing bacteria against tobacco mosaic virus in hot pepper. Accordingly, treatment of hot pepper seeds and plants with rhizobacteria improved hot pepper health and its productivity through the promotion of host nutrition and growth and stimulation of plant host defenses rather than antagonism. In this study, it is demonstrated for the first time that P. fluorescence is effective in management of ChiVMV in chilli.

P. fluorescence reduced the severity of ChiVMV disease in chilli and enhanced

114 RANASINGHE et al. the plant growth in both seed treatment and soil drench application methods. Further, individual treatment of P. fluorescence resulted in different level of ChiVMV control in chilli. Further studies are recommended to increase the efficacy of management of ChiVMV in chilli using P. fluorescence.

REFERENCES

Anonymous. 2001. Identification of RADP markers linked to PVMV and CVMV resistance gene(s) in pepper. Asian Vegetable Research and Development Centre, Progress Report, p 126-128. Damayanthi, T.A. and T. Katerina. 2008. Protection of hot pepper against multiple infections of viruses by utilizing root colonizing bacteria. Journal of ISSAAS. 14(1): 92-100. Damayanthi, T.A., H. Pardede and N.R. Mubarik. 2007. Utilization of root colonizing bacteria to protect hot pepper against Tobacco mosaic tobamovirus. HAYATI Journal of Bioscience. 105-109. Elbadry, M., R.M. Taha, K.A. Eldougdoug and H.G. Eldin. 2006. Induction of systemic resistance in faba bean (Vicia faba L.) to bean yellow mosaic poty virus via seed bacterization with plant growth promoting rhizobacteria. Journal of Plant Diseases and Protection, 113:247251. Maurhofer, M., C.Hase, P. Meuwly, J.P. Metraux and G. Defago. 1994. Induction of systemic resistance of tobacco necrosis virus by the root colonizing P. fluorescence strain CHAO influence of the gac a gene and of Pyoverdine production. Pytopathology 84: 139-146. Parmer, N. and K.R. Dadarwal. 1999. Stimulation of nitrogen fixation and induction of flavonoid- like compounds by rhizobacter. Journal of Applied Microbiology 14: 340-358. Rakib, A., A. Ani, and M.A. Adhab. 2012. Protection of melon plants against Cucumber mosaic virus infection using P. fluorescence biofertilizer. African Journal of Biotechnology 11: 16579-16585. INTEGRATED SOIL MANAGEMENT APPROACH TO ENHANCE THE GROWTH AND YIELD OF CHILLI (CAPSICUM ANNUM)

H.M.P.T.K. HETTIGEDARA 1, M.A.P.W.K. MALAVIARACHCHI 1, R.A.C.J.PERERA 1, W.M.W. WEERAKOON 1, S.P. NISSANKA 2, U.R. SANGAKKARA 2 AND G.H.K. DE SILVA 1

1 Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka 2 Faculty of Agriculture, University of Peradeniya

EXTENDED ABSTRACT

Chilli is one of the most important cash crops grown in Sri Lanka. It has become an essential ingredient in Sri Lankan meals. Though the potential yield is approximately 15 t/ha for green chilli and 3.5 t/ha for dry chilli, the national average yield in 2014 is about 5.13 t/ha and 1.01 t/ha for green chilli and dry chilli respectively (Agstat, 2015). This indicates a large yield gap leading with a very low productivity of chilli crop. A

Annals of Sri Lanka Department of Agriculture 2016. 18: 115 - 110 field experiment was carried out at the Field Crops Research and Development Institute, Mahailluppallama (DL1b agro-ecological region) of Sri Lanka during Maha 2011/2012, Yala 2012 and Maha 2012/2013 seasons with the objective of identifying a package of practices that includes compost application, mulching and deep ploughing to enhance the growth and yield of chilli. The experiment consisted of two plough depths (Deep, 50-60 cm and normal, 20 cm) in the main plot, mulching at the rate of 5 t/ha (Gliricidia mulch and no mulch) and organic manure application at the rate of 10 t/ha (compost application and no compost) in sub plots. Three soil management practices were tested in a split plot design with three replicates. The depth to the gravel layer was at 40 cm in the tested location. The chilli variety MI Green was used as the test crop.

Land preparation was done separately for deep ploughing block and normal ploughing block. The normal ploughing block was prepared using the disk plough and the deep ploughing block was prepared by a backhoe machine to turn the soil up to a depth of 60 cm. Thereafter, the sub plots were prepared within the main plot. Compost made using straw and cattle manure was applied one week before planting at the rate of 5 t/ha and one month after planting at a rate of 5 t/ ha to the beds of the relevant treatments and mixed well with the soil. Air dried Gliricidia leaves were applied as a mulch at the rate of 5 t/ha (dry weight basis) to the relevant treatments at one and two months after planting. For the second and third seasons, to test the long term impact of deep ploughing over seasons, experimental field was prepared using mamoties without using disk plough or backhoe machine. Thus, the land preparation treatment (deep ploughing and normal

116 HETTIGEDARA et al.

ploughing) was applied only one time during the three seasons of the experiment. During the Yala 2012 season the rainfall was very low and due to limitation of irrigation water the crop could not continue for more than three red chilli picks.

Compared to the initial values at the site, bulk density reduced with ploughing. The bulk densities of deep ploughed plots were lower compared to the normal ploughed plots at 35-40 cm soil depth suggesting that the soil layer was loosened due to deep ploughing. At the end of the season, it was clearly shown that the bulk density in the top layer remained same with surface compaction due to cultural practices and surface irrigation while the layer below 25 cm had maintained lower bulk density. The bulk nd density has reduced in the 2 season both in deep ploughed and normal ploughed treatments. Although deep ploughing was not done at the commencement of the 2 nd season the addition of gliricidia and compost may have contributed to reduce the bulk density values.

In first two seasons (Maha 2011/2012 and Yala 2012), the shoot dry weight at the harvesting stage (120 days after planting) was significantly higher in the deep ploughed plots than the normal ploughed plots. The effect of deep ploughing was not significantly different during the 3 rd season (Maha 2012/2013) for the shoot dry weight. The positive impact of deep ploughing on the plant growth may have reduced with time. The root dry weight was significantly higher in the deep ploughed plots than the normal ploughed plots only during the 1 st season. This suggests that the effect of deep ploughing was limited to one season and the impact reduced with time. With the deep ploughing compact layer is broken and the roots are allowed to penetrate into deeper layers.

Interaction effects of the applied treatments on dry chilli yield were not significant. The integrated effects of the applied treatments showed that the total yield was significantly higher during the Maha 2011/2012 season having yield advantage of 136 % in the treatment where deep ploughed, compost and gliricidia mulch were applied than the control where normal ploughed and nor compost or gliricidia mulch were added. The yield in the treatment where normal ploughing, compost and gliricidia mulch was applied was higher than the treatment where deep ploughed but gliricidia or compost was not applied. Therefore, in a situation when the deep ploughing is impossible even in the shallow depth soils application of compost and mulching with gliricidia leaves will enhance the yield by about 69%. Compared to the Maha 2011/2012 season the yields were very much lower during the Yala 2012 season as the drought conditions prevented irrigation water supply and the crop could not continue for more than three picks of red chilli. Application of poultry manure at 5 t/ha, coir dust at 5 t/ha and straw mulch at 4 t/ha combined with half the quantity of recommended chemical fertilizer proved to be the best combination to obtain significantly higher (36%) rice yield than usual nutrient management practice (Jayasundara, 2001).

INTEGRATED SOIL MANAGEMENT TO ENHANCE YIELD OF CHILLI 117

Number of pods per hill and dry chilli yield were significantly higher in the deep ploughed plots than the normal ploughed plots only during the Maha 2011/2012 season. This is because of the better growth of plants in the deep ploughed plots with more biomass. The positive impact of deep ploughing on number of pods per hill and dry chilli yield was not shown in the 2 nd and 3 rd seasons indicating that the effect of deep ploughing had reduced with time. A study done in India with groundnut showed a significantly higher mean plot yield under annually deep ploughed plots than shallow ploughing (Sharma et al., 2014).

The dry chilli yield was significantly higher in the treatments applied with gliricidia mulch than the treatments with no mulch in all three seasons. The positive impact of mulching on the yield was due to addition of organic matter from the gliricidia mulch, additional nutrients from them and moisture conservation. The number of pods per hill and dry chilli yield were significantly higher in the treatments applied with compost than the treatments without compost during the 1 st and 3 rd seasons. That is due to additional nutrients from compost and physical and biological improvement of the soil due to compost application. Application of compost at the rate of 10 t/ha and recommended levels of N, P and K fertilizers increased the number of pods per hill and dry chilli yield in the present study. Deep ploughing up to 50-60 cm depth enhanced the growth and yield of chilli in soils having shallow depth to the gravel layer. Application of compost at the rate of 10 t/ha and gliricidia mulch at the rate of 5 t/ha improved growth and yield of chilli. In situations where deep ploughing cannot be practiced in soils having shallow depth to the gravel layer, application of compost at the rate of 10 t/ha and gliricidia mulch at the rate of 5 t/ha could be recommended as viable crop management practices to enhance the growth and yield of chilli.

REFERENCES

Agstat, 2015. Pocket book of Agricultural statistics. Vol XII. Department of Agriculture, Peradeniya, Sri Lanka. Jayasundara, J.M.P.B. 2001. Effect of integrated application of organic and chemical fertilizer on dry seeded rice (Oryza sativa L.). Annals of the Sri Lanka Department of Agriculture. 3: 61-70. Sharma, G., Maruthi Sankar, G., Akbari, K., Sreenivas Reddy, K., and Sutaria, G. 2014. Efficient Tillage Practice for Maximum Infiltration, Rainwater Use Efficiency, and Profitability from Groundnuts under Semiarid Vertisols in Western India. J. Irrig. Drain Eng. 140(3), 04013019. MANAGEMENT OF MAIZE STEM BORER CHILOPARTELLUS SWINHOE (LEPIDOPTERA: PYRALIDAE) USING SELECTED PLANT POWDERS WITH INSECTICIDAL PROPERTIES

K. N. C. GUNEWARDENA, I.P.S.D. WICKRAMASOORIYA AND K. P. JAYANTHI

Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka

Annals of Sri Lanka Department of Agricultur e 2016. 18:118 - 110

EXTENDED ABSTRACT

Maize (Zea mays L.) is one of the most important cereal crops grown in Sri Lanka. Maize stem borer (MSB), Chilo partellus (Swinhoe) causes a serious damage to maize production. Maize stem borer starts to infest the crop at 3 to 4 weeks after planting and continue up to maturity stage (Subasinghe and Amarasena, 1988). It feeds on young leaves and later bore into the stem, tassels, stalks and ears of the maize plants (Alejandro, 1987; Khan and Amjad, 2000). At present, the management of this pest mainly rely on insecticides applied as foliar spray (Novaluron 10EC, Thiodicarb 375SC, Etofenprox 10EC) as well as granular formulations (Diazinon 5G, Fipronil 0.3G). The use of insecticides can be environmentally disruptive and can result in reducing beneficial insects and accumulation of residues in the harvested produce. Therefore, it is necessary to find alternative control methods which are as effective as pesticides, and without causing harmful impacts to environment. Use of natural products from plant origin is progressively becoming recognized as a potential option. Certain plant families are rich in natural substances with insecticidal properties that could be utilized in the development of safe and alternative methods for pest control (Wheeler and Isman, 2001).

Various field studies conducted have identified several bio-intensive pest management options including ashes, crude plant powders and plant extracts that can be used for the control of different species of field and storage insect pests of maize (Ogendo et al, 2003; Maribet and Aurea, 2008; Yacoub, 2011; Shiberu, 2013). However, information on the local research conducted on botanicals used for MSB control is not available. Therefore, considering the importance of eco-friendly approaches to manage MSB, field studies were conducted at the Field Crops Research and Development Institute, Mahailluppallama during Maha 2014/15 and Yala 2015 to evaluate the efficacy of plant powders from locally available plant species, Ocimum spp. (Basil), Lantana camara (Lantana), Targetes spp. (Marigold) and Azadirachta indica (Neem) against MSB.

Experiments were laid out in a randomized complete block design with four replicates. The treatments tested were leaf powder of Ocimum spp., L. camara, T. spp. and seed powder of A. indica . These treatments were compared with the recommended

MANAGEMENT OF MAIZE STEM BORER USING SELECTED PLANT POWDERS 11 9

Diazinon 5G and an untreated control. The variety MI maize hybrid 1 was used. Plant powders and Diazinon were applied twice as whorl applications at 3 and 5 weeks after planting at a rate of 15 kg/ha (except neem at 5 kg/ha). All the cultural practices recommended by the Department of Agriculture for maize cultivation were followed. Percentages of MSB damaged plants were recorded before the application of plant powders and insecticides and at 4 and 8 weeks after planting. Number of stem borer larvae and pupae in 10 randomly selected plant stems was recorded at 8 weeks after planting. Severity of leaf damage was rated using a scale and severity index was calculated. The grain yield was recorded at the harvesting stage. Data analysis was done using Analysis of Variance and means were compared using the Duncan's Multiple Range Test. Data on percentages and counts were subjected to appropriate transformation before performing the Analysis of Variance.

The percentage of stem borer damaged plants was not significantly different among the treatments before application of plant powders and insecticides. The percentage of stem borer damaged plants in the plots treated with different plant powders and untreated control varied from 14 to 20 % while the damage in the Diazinon 5G treated plots was 1.8 % at 4 weeks after planting during Maha 2014/15. At 8 weeks after planting, the percentage damaged plants in the plots treated with different plant powders varied from 17 to 27 % while the damaged plants in the untreated plot was 40 %. The lowest damage (4 %) was recorded in the plots treated with Diazinon 5G. During Yala 2015, at 8 weeks after planting all the plots treated with plant powders except T. spp. (Marigold) and Diazinon treated plots showed significantly lower percentage of damaged plants compared to untreated control (36 %). Diazinon 5 G found to be superior in reducing stem borer damage during both seasons.

The larval and pupal populations in 10 plants stems were significantly lower in Ocimum spp., L. camara, A. indica and Diazinon 5G treated plots compared to that in the untreated control in both seasons. This could be because of the insecticidal effect, repellent or anti-feedant activity of these plant powders. The percentage reduction of stem borer population ranged from 28-59% and 38-51% in plant powders treated plots and 77% and 74% in Diazinon 5G treated plots over the control plot during Maha 2014/15 and Yala 2015, respectively. The severity of stem borer damage was significantly low in plant powders of Ocimum spp., L. camara, A. indica and Diazinon 5G treated plots compared to the untreated plot during both seasons.

All the plant powders except Targetes spp. (Marigold) treated plots and Diazinon 5G treated plots gave significantly higher yields than the untreated control plots during Maha 2013/14. However, there was no significant difference in yield between plant powders treated plots and untreated control during Yala 2015. Application of crude powders of Ocimum spp., L. camara, A. indica increased the maize grain yields by 4345% and 24-27 % compared to the untreated control during Maha 2014/15 and Yala

120 GUNAWARDENA et al.

2015, respectively. The diazinon 5G applied plots increased the grain yield by 63% and 51% compared to the untreated control during Maha 2014/15 and Yala 2015, respectively.

Maize plants treated with crude, dry powders of Ocimum spp. (@15 kg/ha), L. camara (@15 kg/ha) and A. indica (@5kg/ha) showed significantly low stem borer incidences, pest populations and higher yields as compared to those received no treatment. The plants treated with Diazinon 5G had the lowest stem borer damage and highest yield. Therefore, crude powders of these plants can be used as alternative crop protectants to synthetic insecticides in integrated pest management programs for the control of C. partellus in maize. Further research is needed to determine the mode(s) of action of these plant powders and to validate these results under farmer field conditions.

REFERENCES

Alejandro, O.C. 1987. Insect Pests of Maize. A guide for field identification. International Maize and Wheat Improvement Centre, Mexico. 106p. Khan, S.M. and M. Amjad. 2000. Chemical control of maize stem borer (Chilo partellus Swin.). Pakistan Journal of Biological Sciences 3: 2116-2118. Maribet L.P. and C.R. Aurea. 2008. Insecticidal action of five plants against maize weevil, Sitophilus Zeamais Motsch. (Coleoptera: Curculionidae) Kmitl. Sci. Tech. Journal 8: 24-38. Ogendo, J.O., S.R. Belmain, A.L. Deng and D.J. Walker. 2003. Comparison of toxic and repellent effects of Lantana camara L. with Tephrosia vogelii Hook and a synthetic pesticide against Sitophilus zeamais Motsch. (Coleoptera: Curculionidae) in stored maize grain. Insect Science and Its Application 23: 127-135. Shiberu T. 2013. Evaluation medicinal plant powder on maize stem borer, Busseola fusca F. (Lepidoptera: Noctuidae) under laboratory condition. International Journal of Agriculture and Crop Sciences 6: 534-538. Subasinghe, S.M.C. and J. Amarasena. 1988. Temporal distribution and chemical control of the maize stem borer, Chilo partellus Swinhoe (Lep.; Pyralidae). Tropical Agriculturist 144: 123-133. Wheeler, D.A. and M.B. Isman. 2001. Antifeedant and toxic activity of Trichilia americana extract against the larvae of Spodoptera litura. Entomologia. Experimentalis et. Applicata 98: 9-16. Yacoub, S.H. 2011. Utilization of certain plant extracts to reduce the infestation of pink stem borer Sesamia cretica Led. in maize fields. Egypt. J. Agric. Res., 89: 155-167.

Annals of Sri Lanka Department of Agriculture 2016. 18: 121 - 114

CRITICAL PERIOD OF WEED CONTROL IN BIG ONION (ALLIUMCEPA L.) UNDER TWO DIFFERENT AGRO-ECOLOGICAL ZONES OF SRI LANKA

D.P.P. LIYANAGE 1, D.R. WENAKA 2, D.L. WATHUGALA 3 H.R.C. NIROSHANI 1 AND D.S. YAPA 4

1 Grain Legumes & Oil Crops Research & Development Centre, Angunakolapelessa, Sri Lanka 2 Mahaweli Authority of Sri Lanka, Walawe special area, Embilipitiya, Sri Lanka. 3 Faculty of Agriculture, University of Ruhuna, Mapalana, Kamburupitiya, Sri Lanka 4 Agriculture Research Station, Department of Agriculture, Weerawila, Sri Lanka

EXTENDED ABSTRACT

Big onion is one of the important condiment crops in Sri Lanka. A large number of farmers engage with big onion cultivation and every year government spend large amount of foreign reserves to import big onion to fulfil annual requirement of Sri Lanka. According to Department of Senses and Statistics, 2014 report, 15, 278 farmers cultivated big onion in year 2014 and the number of farmers engage with big onion cultivation is increased year by year. The average onion yield in Sri Lanka is lower than the maximum potentials that could be achieved with the cultivars that are used. There are several reasons for yield reduction. They are weeds, pests and diseases and other abiotic stresses. Among them the main reason for lower than expected yield is weed competition, because of the peculiar canopy structure of the onions.

Critical period of weed control (CPWC) is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of big onion, field experiments were conducted during 2014/2015 at two different agro-ecological zones (DL 1b and

DL 5) of Sri Lanka. A quantitative series of treatments comprising two components, (a) increasing duration of weed interference and (b) increasing length of weed-free period, were imposed. (a) Increasing duration of weed interference (referred to as weedy plots) Weeds were allowed to compete with big onion from seedling establishment until 2, 3, 4, 5, 6, 7, 8, and 9 Weeks after transplanting (WAT). Then plots were maintained weed-free until harvest. (b) Increasing length of weed-free period (referred to as weed-free plots). Increasing length of weed free period was maintained by removing weeds until 2, 3, 4, 5, 6, 7, 8 and 9 WAT. Then subsequent emerging weeds were allowed to compete for the remainder of the growing season. In addition, whole season weedy plot

122 LIYANAGE et al. and weed- free plot were maintained as controls in each block.

Timing of weed removal was based on the number of WAT of big onion seedlings. The experiment was conducted under naturally occurring population of mixed weed species. Critical period was determined through Logistic and Gompertz equations. Fresh bulb weight was recorded at harvesting. The CPWC was determined by fitting Logistic and Gompertz nonlinear equations to relative yield loss data. Four acceptable yield loss levels (5, 10, 15 and 20%) were considered. To determine the critical weed free period, Non-linear equations were used to describe crop yield response against weed interference. The three parameter’s Gompertz equation (Johnson et al., 2004) was used to describe the effect of increasing duration of weed-free period on onion yield.

RY= a*exp [-exp (-(x-x0)/b)] ------[1] Where, RY is the relative yield (% season-long weed-free yield), a is the upper limit, xo is the days to give 50% yield, x is the number of days and b is the slope.

A three parameters Logistic equation was used for describing the effect of increasing the length of weed-interference on relative yield (Johnson et al., 2004):

RY = if(x<=0, if(b<0,0,a), if(b>0, a/(1+abs(x/x0) Ab), a*abs(x/x0) A(abs(b))/(1+(abs(x/x0)) A(abs(b)))...... [2]

Where, RY is the relative yield (% season-long weed-free yield), a is the upper limit, x 0 is the days to give 50% yield, x is the number of days and b is the slope.

The Gompertz and Logistic equations were fitted with the Sigma Plot software. The logistic equation was used to determine the beginning of the CPWC, and the Gompertz equation was used to determine the end of the CPWC for yield loss levels of 5% 10% and 20% chosen arbitrarily (Martin et al., 2001).

According to the field studies conducted at two locations in two agro-ecological zones of Sri Lanka weeds are a serious threat to big onion crop. Data showed that weed causes 77-100% yield losses in big onion fields in the case of no weed control. (Figures 1, 2, 3 and 4). The CPWC of big onion in DL5 zone during Maha season was 15-100, 1862, 20-54 and 22-49 days after transplanting (DAT) for acceptable yield loss levels respectively. Meanwhile, 9-68, 12-60, 15-54 and 18-49 DAT were observed as CPWC in DL1b zone during Yala season.

123 CRITICAL PERIOD OF WEED CONTROL IN BIG ONION

Gompertz Equation: RY= 108.19*exp(-exp(-(x-21.7333)/22.8168)) R2= 0.8376 P<0.05 Logistic Equation: RY= 100.8574/ (1+abs(x-33.9876) A33.9876) R 2= 0.915, P<0.05

Figure 1: influence of weed interference on relative yield of big onion in the agro-ecological zone DL 1b during Yala season. Increasing duration of weed interference data fitted to the logistic equation; increasing weed-free period data fitted to the Gompertz equation.

Gompertz Equation: RY= 173.61*exp(-exp(-(x-51.084)/68.44)) R2= 0.7467 Logistic Equation: RY= 97.5337/ (1+abs(x-46.7214) A2.0836) R2= 0.7571, P<0.05

Figure 2: influence of weed interference on relative yield of big onion in the agro-ecological zone DL 1b during early Yala season. Increasing duration of weed interference data fitted to the logistic equation; increasing weed-free period data fitted to the Gompertz equation.

Gompertz Equation: RY= 95.836*exp(-exp(-(x-26.931)/10.2245) R2= 0.9313 P<0.05 Logistic Equation: RY= 102.7108/ (1+abs(x-33.5416) A3.277) R2= 0.9699 P<0.05

Figure 3: influence of weed interference on relative yield of big onion in the agro-ecological zone DL 5 during Maha season. Increasing duration of weed interference data fitted to the logistic equation; increasing weed-free period data fitted to the Gompertz equation.

Gompertz Equation: RY= 105.1329*exp(-exp(-(x-32.6057)/11.834) R2= 0.8620 P<0.05 Logistic Equation: RY= 81.9602/ (1+abs(x-48.9049) A6.5979) R2= 0.8187 P<0.05

Figure 4: influence of weed interference on relative yield of big onion in the agro-ecological zone DL 5 during Yala season. Increasing duration of weed interference data fitted to the logistic equation; increasing weed-free period data fitted to the Gompertz equation.

124 LIYANAGE et al.

These results revealed that weed is a serious threat to onion cultivations in DL 1b and DL 5 zones and fields should be kept in weed free for much of the growing season to reduce considerable yield reduction. However these periods can be varied according to weed densities, agronomic practices and climatic conditions. Application of integrated weed management practices throughout the growing season instead of total dependence on herbicides can be recommended.

REFERENCES

Johnson, D.E., Wopereis, M.C.S., Mbodj, D., Diallo, S., Powers, S. and Haefele, S.M. 2004. Timing of weed management and yield losses due to weeds in irrigated rice in the Sahel. Field Crop Res 85: 31-42. Martin, S.G., R.C. Van Acker and L. F. Friesen. 2001. Critical period of weed control in spring canola. Weed Sci. 49:326-333.

Annals of Sri Lanka Department of Agriculture 2016. 18: 125 - 110

EFFECT OF 1 -METHYLCYLOPROPENE (1-MCP) ON POSTHARVEST QUALITY AND SHELF LIFE OF OKRA

H.R.P. FERNANDO, MR. PRASANGIKA AND W.G.B.R. ARIYARATNE

Agriculture Research and Development Centre, Girandurukotte, Sri Lanka

EXTENDED ABSTRACT Okra (Abelmoschus esculentus L.) is one of the widely consumed and economically viable vegetable crops grown in tropical and sub-tropical areas. Fresh okra is commonly used in various food items including soups, stews, curry and steamed vegetables. It is also a good source of fibre, protein, minerals and vitamin C and diet- viscous mucilage. Fresh okra is a perishable vegetable, which has a short postharvest life. Loss of quality in harvested okra is usually manifested with shrivelling, toughening, and chlorophyll degradation would change the colour and texture of fresh okra leading to rejection by the consumer. The actions of ethylene contribute to making above changes. Ethylene quickens the deterioration process of okra and reduces the market life of the pods. The gaseous ethylene blocking compound 1-methylcyclopropene (1-MCP) prevents ethylene-dependent responses, has been used for decades to maintain postharvest quality of various products. Therefore, the objective of this study was to investigate the effects of 1-MCP fumigation on postharvest quality parameters and shelf life of harvested okra during storage.

Half mature green okra pods of the variety Haritha were selected for uniformity in green colour, size and free from defects or physiological disorders. Selected pods of okra were randomly divided into three lots with the first lot being fumigated with 0.5pL L-1of 1-MCP for three hours (Blankenship and Dole, 2003) at 28±2 °C, second lot with 1 pL L -1of 1-MCP for three hours at 28±2°C, and the third lot was used as the control without 1-MCP treatment. The experiment was arranged in a Complete Randomize Design (CRD) with four replicates. The treated materials were stored for 12 days at 28±2°C and 85% RH. Weight loss, Total soluble solids (TSS), crude fibre content, disease incidence, pod colour change, marketability, and shelf life were measured during 2 days intervals as the quality parameters.

Both 1-MCP concentrations used reduced the weight loss compared to the control at 28±2°C. The reduction of weight loss could be due to the suppression of respiration rate. Scientists have reported that 1-MCP treatments inhibited the level of increase of ethylene-induced respiration in fruits and vegetables. Suppression of weight loss and respiration rate was correlated as 1-MCP reduced the respiration rate through inhibition of ethylene synthesis. The 1-MCP at the concentration of 1 pL L -1 reduced the weight loss at a higher rate compared to at 0.5 pL L -1 and the control.

126 GUNAWARDENA et al.

Increasing of TSS in fruits during maturation and ripening due to degradation of starch into soluble sugar within the cell. TSS content of all treatments used in this study decreased from day 0 to 8. The reduction in TSS content is a typical character in okra due to decrease in the content of viscous mucilage and soluble sugars with lignifications of tissues. Both 1-MCP treatments retained the TSS at higher levels than in the control. Therefore the low lignification rate has a direct impact on the samples fumigated with 1- MCP.

The crude fibre content of all samples increased during storage. The crude fibre content of okra fumigated at 1-MCP concentrations were significantly lower (p<0.05) than the crude fibre content of the control from day 4 to day 12. These results suggest the relationship between ethylene production and the fibre development of harvested okra. The 1-MCP is an anti-ethylene compound, which blocks ethylene receptors in the tissues and prevents or delays the ethylene production. The lower fibre content of okra fumigated with 1pL L -1of 1-MCPthan that in the concentration of 0.5 pL L -1suggest that the fibre formation of harvested okra has a direct relationship with the ethylene concentration.

The bright green colour of all okra samples started to reduce after 2 days. The colour change of the control sample was more marked than those fumigated with 1-MCP. After day 12, 1-MCP at the concentration of 1 pL L -1significantly conserved (p<0.05) the green color of okra than in those the control. Yellowing of many fruits and vegetables due to chlorophyll degradation has been accelerated by ethylene. Results of the present study have confirmed that 1-MCP at concentrations of 1and 0.5 pL L -1 have delay yellowing of okra. This is probably the result of delaying chlorophyll degradation through 1-MCP action.

The disease incidence of all okra samples progressed during the storage. The disease incidence of okra treated with 1 pL L -11-MCP was significantly low (p<0.05) compared to the control from day 4 to 12. The disease incidence of okra fumigated with 0.5 pL L -1of 1-MCP and that in the control increased in a similar manner until day 6. No disease symptoms were observed in okra fumigated with 1-MCPA at 1 pL L -1from day to 4. Thereafter, the disease incidence of okra in the control increased rapidly compared to okra treated with 1-MCP. Previous studies have reported of the action of 1-MCP against diseases and physiological disorders of fruits and vegetables. 1-MCP contributes to

MANAGEMENT OF MAIZE STEM BORER USING SELECTED PLANT POWDERS 1 27 accelerating of some antioxidant enzymes of plant tissues through inhibition of ethylene evolution could be a reason to the development of resistance in tissues through strengthening the natural defence mechanism in plant tissues.

Marketability of all okra samples started to reduce after day 2 of storage in a similar pattern. The marketability of okra samples treated with 1-MCP started declining later than those in the control. The marketability of okra in the control became zero at the 12 th day of storage, while it was low compared to those fumigated with 1 qL L -1 of 1- MCP after day 6. The general consumer preference of okra depends on fresh appearance; pod shape, green colour, toughening and shrivelling, and disease development were maintained at acceptable levels after fumigation with 1-MCP. However okra fumigated with 1 qL L -1of 1-MCP showed a better marketability than those treated with 0.5 qL L -1 of 1-MCP.

Shelf life of okra samples determined at 50% marketability in the control, and fumigated with 0.5 and 1 qL L -1of 1-MCP was 7, 9 and 11 days, respectively, based on standard criteria proposed by National Agricultural Research Institute of Ghana. The marketability of okra in the control reached 50% level at day 7 while those fumigated with 0.5 and 1 qL L -1of 1-MCP reached the 50% marketability level at 9 and 11 days, respectively. Shelf life of okra fumigated with 1 qL L -1of 1-MCP recorded the maximum shelf life (11 days) due to delayed chlorophyll degradation, fibre formation, water loss and disease development.

Fumigation of okra with 1 -MCP is a favourable technology for the commercial application for maintaining quality, extending shelf life and reducing postharvest losses at storage temperature of 28±2 °C. The 1-MCP at 1 qL L -1 showed better performance than 0.5 qL L -1 on improving postharvest quality and shelf life of okra.

Annals of Sri Lanka Department of Agriculture 2016. 18:128 - 114

INDUCED FLOWERING WITH ARTIFICIAL LIGHT FOR YEAR ROUND PRODUCTION OF DRAGON FRUIT IN SRI LANKA

S.A.S.M. KUMARI, M.A.D.K. MANNANAYAKE, W.M.S. WARNASOORIYA M.A.L.R. MUNASINGHE AND K.N. KANNANGARA

Regional Agriculture Research and Development Centre, Makandura, Gonawila (NWP), Sri Lanka

EXTENDED ABSTRACT

Dragon fruit is one of the newly popularize tropical fruit coming under the family Cactaceae. It is believed that dragon fruit was originated in North Central America, South America and Mexico and now it has widely spread to tropical region in the world. It is extensively grown in Vietnam and Taiwan; they are the major exporters in the world. It has received recognition as fruit crop and ornamental plant in the world. According to the Nandwani (2011), it has special anti-oxidant properties which help to control blood presser, blood glucose levels, as well as reduce cancer causing risk and enhance immunity levels and also it is good source for vitamin C, calcium and prosperous. Dragon fruit was introduced to Sri Lanka in 1997 by a private grower and thereafter, it has been cultivated throughout the country during last decades. According to Senevirathne et al. (2012), the cultivated extent of dragon fruit was 1,200 ha in 2012 and now it has expanded up to 1,500 ha. Dragon fruit is now cultivated successfully in all over the island with supplementary irrigation.

Flowering of dragon fruit depend on day length because it is photo period sensitive plant (Gunasena and Pushpakumara, 2006); therefore, dragon fruit is produced fruits seasonally in Sri Lanka. Though, Sri Lanka is tropical country, it has maximum 50 minutes diurnal variation of day light in between longest day at June to shortest day at December. For flowering of dragon fruit needs more than 12 hours day period that is called long day plant. Under natural condition it has well defined ordinary fruiting season from May to October and off season from November to April. Manipulation of the flowering season in dragon fruit can be possible through night breaking with supplying artificial lights (Leonardo et al., 2013). Many dragon fruit producing countries practiced night braking technology for flower induction and fruit setting during off-season and thereby to cater premium market and produce fruits throughout the year.

Induced flowering with artificial light for year round production was conducted from December 2013 to May 2016 and used eight years old cultivation having white fleshed variety. The trial fields were established as one vine per post with the spacing of

2 m x 2.5 m in triple row system. Twenty watts compact florescent bulbs (CFL) were

INDUCED FLOWERING WITH ARTIFICIAL LIGHT IN DRAGON FRUIT 129 used for supplying artificial light and they were placed at the middle of 4 plants at a height of one foot above the plant canopy. According to the last three years ordinary fruiting season, the fruit production consist with twelve production picks, which is coming 10 to 15 days intervals, including seven major picks with an average of 15 fruits per plant per season.

Phase I of the experiment was designed as RCBD with three replicates to find the optimum duration for night breaking out of five time durations (2 hours, 2 !4 hours, 3 hours, 3 hours and 4 hours) by supplying artificial light starting from 7.00 pm to 11.00 pm for continuously for 18 days and discontinued for three days to induce flowering and control (without light). The lowest average yield was recorded with 2 hours duration and 3 hours, 3 !4 hours, 4 hours durations produced higher yield while there was no fruiting without artificial light. According to the observational study done by supplying 1% hours light period showed no flower induction during off season suggesting that the optimum time duration for artificial lighting lies between 1.5 to 2 hours. Fruits quantitative and quality (TSS) parameters were not statistically difference in all lighting treatments and suggesting that fruit growth is not affected by artificial lighting. However, average numbers of fruits produced in 3, 3 %, 4 hr treatments were statistically different from 2 hours treatments.

It has also been reported that night breaking with supplemental lighting from 10.00 pm to 2.00 am could be used for flower induction in dragon fruit (Tran et al, 2015; Leonardo et al., 2013; Nguyen, 2008; Zee et al., 2003). Nguyen (2008) reported that 8-10 pm night break is enough for flower induction of dragon fruit in Vietnam. Therefore, the second phase of experiment was conducted to find out optimum time to start night break. This experiment was designed as RCBD with two factor factorial to reduce number of days per night break cycle and find out optimum time for night braking between 7 pm to 5 am. Factor one was lighting time which were from 7-9 pm, 9-11 pm, 11 pm-1 am, 1-3 am, 3-5 am and factor two was length of days continuing for supplying lights which was 12 days, 15 days and 18 days. According to findings all treatments differences were not statistically significantly from each other. Average yield and average number of fruits were high in between 7-9 pm, and 11 pm -1 am, mid night break treatment. Further illuminating from 7 to 9 pm is convenient for small farmers as it can be controlled manually without timers. There was no difference in average fruit weight and TSS (brix) value among treatments.

130 KUMARI et al.

Length of days per lighting cycles to induce flowers was practiced 12 days, 15 days and 18 days which was continuing for supplying lights. According to the observations, 18 days continuous supply of artificial light significantly increased the number of flowers, but did not show any difference in number of fruits and total average yield. There was a consistent increase in flower bud number with increase the duration of artificial light. However, statistical significant differences were observed only at Dec 15 - Jan 15 period with 18 days duration when compared with other durations from Jan 15 to April 15. After Jan 15, mean numbers of flower buds in different length of light supplying days were not statistically significant. Therefore, initially November, December and January 18 days lights and 3 days switch off could be practiced and there after 12 days light and 3 days switch off could be practiced up to mid of April.

Though dragon fruit production is ordinary coming in one season per year, same plants can produced off season production with artificial light. It was observed off season production do not clash with seasonal production and it remain same while off season production was significantly higher than seasonal production. All off seasonal production produced more than 9.5 kg/plant and ordinary production were 5 kg/plant.

Three hours artificial light from 7 pm to 10 pm is enough to obtain maximum off seasonal production. Light supply is needed to start during November and continue to January with 18 days light supplying cycle with 3 days discontinued. There after 12 days light supply with 3 days switch off can be practiced during February to April using CFL 20W bulbs. CFL bulbs can penetrate lights even to lower branches and receiving light intensity was enough to induce flower buds. After flower bud initiation, subsequently 17 days flower development take placed and blooming and pollination took another day. 30 days after blooming ripens fruits were harvested. Therefore average of 50 days was needed for fruiting cycle for the development of bud, blooming, pollination, fruit development and fruit harvest.

Proper canopy management is needed for continuous production. Normally pruning is done one time per year and it is practice at the end of seasonal production in November, but that is not adequate to produce year round production because every time newly produced branches produced fruits during normal season. Therefore, plants need to be pruned during November to induce flower buds during end of April. Again light pruning was done at the end of off season to remove mutual shaded very old branches, unhealthy branches and to remove braches at the ground level. When night breaking was started at 1 st of November, night break continued, first off season harvest could be obtained at the 1 st week of January and thereafter 6-7 off seasonal production flushes could be obtained up to mid of May.

Initial investment was high for material and installation of the field wiring and it was about 0.52 million per hectare land with 1,000 posts, but it can be covered even

INDUCED FLOWERING WITH ARTIFICIAL LIGHT IN DRAGON FRUIT 131 during 1 st off season due to large production and attractive off season market price. There after only electricity charge added to cost. All the wiring items can repeatedly be used for several seasons without trouble. According to income and profit analysis during season and off season production, findings suggest that with artificial light during off season production, total income from dragon fruit cultivation could be increased by three times. Peek off seasonal flower induction occurs during February and March and normally these months get low rain fall. It may affect pollination and flower buds may be fallen and reduce fruit size due to lower viability of pollen. To avoid this constrains supplementary irrigation is needed during dry months of February and March. To have continuous bearing, proper nutrient management strategy is needed.

REFERENCES

Gunasena, H.P.M. and Pushpakumara, D.K.N.G. 2006. Dragon Fruit - Hylocereus undatus (Haw.) Britter and Rose; A fruit for the future.Sri Lanka Council for Agriculture Research Policy, Colombo, Sri Lanka. Leonardo, T.P., Gabriel, M.L.S., Gabriel, M.D. and Pascua, M.E. 2013. Evaluation of light bulbs and the use of foliar fertilizer during off-season production of dragon fruit, Ilocos Agriculture and Resources Research and Development Consortium, Mariano Marcos State University, Batac City. Nandwani, D. 2011. Dragon Fruit (Pitaya) Hylocereussp. Northern Marianas College Cooperative Research, Extension and Education Service and US Department of Agriculture (USDA), Saipan. Nguyen, V.H. 2008.Current Research Activities and The Development of Good Agricultural Practice (Gap) for Pitaya in Vietnam, itfnet.org, Southern Horticultural Research Institute (SOFRI), Longdinh, Chauthanh, Tiengiang, Vietnam. Seneviratne, K.G.S. and Perera, K.T.M.S. 2012. Flower bud pollination during day time for higher fruit set in red fleshed dragon fruit (Hylocereus spp.). Annals of the Sri Lanka Department of Agriculture. 14: 287-292. Tran, D.H., Yen, C.R. and Chen, Y.K.H. 2015. Flowering Response of a Red Pitaya Germplasm Collection to Lighting Addition. World Academy of Science, Engineering and Technology, International Journal of Biological, Biomolecular, Agricultural, Food and Biotechnological Engineering, 9-2: 176-179 Zee, F., Yen, C.R. and Nishina, M. 2004. Pitaya (Dragon Fruit, Strawberry Pear). Cooperative Extension Service, Coll. Trop. Agri. Human Resources (CTAHR), Univ. Hawaii.Fruits and Nuts F&N-9, 3 pp. ASSESSMENT OF GENETIC VARIABILITY IN RECOMBINANT INBRED LINES OF CHILLI (CAPSICUM ANNUUM L.)

H.M.S.N. HERATH 1, W. M. W. WEERAKOON B. MARABME 2, A.M. PEREARA 1, J.M.J.B. SENANAYAKE 1, H.M.S. BANDARA 1

1 Field Crops Research and Development Institute Mahailuppallama, Sri Lanka 2 Faculty of Agriculture, University of Peradeniya, Sri Lanka

EXTENDED ABSTRACT

Chill is an economically important condiment in Sri Lanka and cultivated

Annals of Sri Lanka Department of Agricultur e 2016. 18:132 - 110 mainly for green and dry chilli. In 2014, 13,978 ha of chilli was cultivated with the production of 71,767 t. In the same year, 46,422 t of dry chilli was imported with the value of 7,578 million rupees (DOA, 2014). Even though green chilli production is sufficient to fulfil local demand, dry chilli production is not sufficient. Performance of available open pollinated chilli varieties has not sufficient to increase the productivity of chilli cultivation. Local farmers prefer to cultivate imported chilli hybrid varieties with the purpose of achieving higher yield. But, these hybrid varieties do not perform well under local farming condition. Therefore, development of superior hybrid chilli varieties and open pollinated chilli varieties adapted to local condition is very important to increase the productivity of chilli cultivation in the country. Recombinant inbred lines are developed mainly for the heterosis breeding. Genetic variability among inbred lines are very important to select better parents to develop superior chilli hybrids. Open pollinated chilli varieties can be developed using the inbred lines through hybridization and selection. Coefficients of variation assess the magnitude of variability present in a population. Estimates of heritability and genetic advances are important preliminary steps in any breeding program as it provides information needed in designing the most effective breeding program (Jalal and Ahmad, 2012). As an initial step of developing new high yielding open pollinated and hybrid chilli varieties, this study was conducted to assess the genetic variability of recombinant inbred lines considering the mean performance, genotypic and phenotypic variance, coefficients of variation, heritability and genetic advance.

This study was conducted during Yala 2015 and Maha 2015/16 at the Field Crop Research and Development Institute (FCRDI), Mahailluppallama. Sixty-eight recombinant inbred lines developed at the FCRDI were used in this study. Thirty days old seedlings of inbred lines were planted during Yala 2015 in a randomized complete block design with two replicates with plot size of 6.0 x 1.8 m consisted of five rows of plants at

133 GENETIC VARIABILITY IN RECOMBINANT INBRED LINES OF CHILLI the spacing of 60 x 60 cm and two plants per hill. Each plot contained 100 plants. Five plans were randomly selected per treatment and observations were recorded on plant height, canopy width, pod length, pod diameter, pericarp thickness. Number of days which was taken to start the flowering of 50% plant from each treatment was taken as days to 50% flowering. Harvesting was started 75 days after field planting and continued at 10 day intervals. Number of pods and fresh green chilli yield of each treatment were recorded at each harvesting. Same procedure was followed during Maha 2015/16 season. Variability among genotypes was ascertained by SAS. Mean separation was done by Duncan Multiple Range Test. Genotypic variance (o 2g) and phenotypic variance (o 2p) were obtained from analysis of variance table according to Comstock and Robinson (1952).

Significant difference among the recombinant inbred lines was observed for all the tested characters other than number of pods/plant. There was a significant effect on season for the tested agronomic characters other than plant height. Interaction between season and treatment was significant for pod length, pod diameter, plant height, canopy width and days to 50 % flowering. Mean, maximum and minimum values on agronomic characters confirmed the variability associate with the inbred lines. None of the inbred lines performed well for all the tested characters during both season indicating the high environmental effect on the expression of tested agronomic characters. Performance of the inbred lines on tested characters was varied depending on the season. Among the recombinant inbred lines, highest yield was recorded in MICH PL 35, MICH PL 37 and MICH PL 38 exhibiting the stability over seasons. Profound effect of environmental factors on quantitative traits of chilli was observed by Chaim and Paran (2000).Larger reduction on mean performance of yield was observed during Maha season for all the inbred lines. Phenotypic variance showed a higher value than genotypic variance indicating greater influence of environment for the tested quantitative characters. High genotypic coefficient of variance (GCV) and phenotypic coefficient of variance (PCV) were observed for characters, yield, number of pods/plant, pod length, pod diameter and pericarp thickness. This indicates the high variability of these characters that offer good scope for selection of parents for the development of chilli hybrids. Moderate GCV and PCV values were observed in plant height and canopy width suggesting that these traits have less potential for selection. Therefore, heterosis breeding is a good option to increase plant height and canopy width. The lowest GCV and PCV were observed for days to 50% flowering. Similar result was reported by Manju and Sreelatha Kumary (2002). High heritability, high genetic advance and high GCV were exhibited for pod characters indicating the presence of fixable additive genetic effect. Therefore, pod characters can be improved through hybridization and selection. High heritability for pod

134 HERATH et al. characters indicated that large proportion of phenotypic variance due to genotypic variance. This further confirms the reliability of selection for these traits on the basis of phenotype of chilli.

There was high genetic variability among the recombinant inbred lines. There is greater potential of utilizing the developed inbred lines for the development of superior chilli hybrids and open pollinated varieties. Characters such as yield, number of pods/plant, pod length, pod diameter and pericarp thickness that exhibited high genotypic coefficient of variance and phenotypic coefficient of variance offer good scope for selection of parents for the development of chilli hybrids. Mean performance of agronomic character indicated that inbred lines, MICH PL 35, MICH PL 37 and MICH PL 38 can be exploited for further testing to release directly as open pollinated varieties.

REFERENCES

Comstock, R.R. and H.F. Robinson, 1952. Genetic parameters, their estimation and significance, proc. 6 th international Grassland Congress. Nat. Publ. Co. Wash. D.C. U.S.A., 1: 248291. Chaim, A.B. and I. Paran. 2000. Genetic Analysis of Quantitative Traits in Pepper (Capsicum annuum) Journal of American Society of Horticultural Science. 125(1): 66-70. DOA. 2014. Agstat. Socio Economic and Planning Centre. Department of Agriculture. Peradeniya. 11:16. Jalal, A., H. Ahmad, 2012.Genetic Variation, Heritability, Phenotypic and GenotypicCorrelation Studies for Yield and Yield Components inPromising Barley Genotypes.Journal of Agricultural Science.4 (3): 193 - 210. Manju.,P.R. and I. Sreelatha Kumary. 2002. Genetic variability, heritability and genetic advance in hot chilli. Journal of tropical Agriculture.40: 4-6.

Annals of Sri Lanka Department of Agriculture 2016. 18: 135 - 114

Short Communication

SEEDLING DIPPING AS A METHOD FOR PHOSPHORUS FERTILIZATION IN RICE GROWN UNDER PHOSPHOROUS-DEFICIENT SOILS USING PARACHUTE TRANSPLANTING

W. R. K.D.W.K.V. WICKRAMASINGHE, S. P. GUNARATHNE,

K.D.S. SAMARARATHNE AND K.K.D. CHANDRASEKARA

Regional Rice Research and Development Centre, Bombuwela, Sri Lanka

INTRODUCTION Soil degradation has been identified as a major constraint and a root cause of declining crop productivity in many developing countries (Fukuda et al., 2012). Improvement of soil fertility and plant nutrition is essential to sustain adequate yield of rice crop. Therefore, application of nitrogen, phosphorus and potassium fertilizers for paddy fields in Sri Lanka has increased continuously since 1960. Phosphorus (P) is the second limiting macronutrient for enhanced plant growth and yield next to nitrogen (N). It is involved in the supply, transfer and storage of energy for all biochemical processes within the plant (Khan et al., 2009). Rice (Oryza sativa) crop requires about 3-4 kg P for production of one ton of rough rice per hectare including straw (Sahrawat, 2000). Continuous rice cropping without P fertilization causes depletion of the soil P level even in fertile soils in the long run (BRRI, 1996). Thus, application of P fertilizer is essential to meet the crop demand as well as for the maintenance of soil P level.

Kendaragama et al . (2003) reported that a higher level of P application with limited supply of other nutrients in the long run could lead to excess availability of P in paddy soils. This soil-P might get transported to water bodies with irrigation water. Thus, use of heavy doses of fertilizer could increase eutrophication of surface water bodies. In addition, Chronic Kidney Disease of Unknown Etiology (CKDu) is a long standing health problem in the Dry zones areas and heavy metal contained in P fertilizer has been suspected to cause this disease (Bandara et al., 2008). The general method of P application for rice cultivation is the surface broadcasting before transplanting. A method of P fertilization with the use of small quantities such as fertilizer soaking/dipping has drawn attention of scientists and practitioners in some countries. De Datta et al. (1996) have reported that dipping rice seedling roots in a P soil-slurry reduced the fertilizer requirement of the crop by 50%. Therefore, application of P to seedling roots in the form of slurry before transplanting rice could be an economical and environmentally-friendly method to improve seedling establishment and growth and yield of rice. A field experiment was thus, conducted to evaluate seedling dipping in P

136 WICKRAMASINGHE et al. slurry for a rice crop that uses parachute method for transplanting rice.

MATERIALS AND METHODS

The field experiment was conducted at the Regional Rice Research and Development Centre at Bombuwela in Sri Lanka during the period of 2015 Yala to 2015/16 Maha seasons. The experiment was laid out in a randomized complete block design with three replicates. Treatments were T1 - No fertilizer, T2 - broadcasting of N, P and K fertilizer at the dosage recommended by DOA, T3 - P fertilizer at DOA recommended dosage applied by seedling dipping, T4 - 3/4 th of the DOA recommended P fertilizer applied by seedling dipping, T5 - 1/2 th of the DOA recommended P fertilizer applied by seedling dipping, T6 - 1/4 th of DOA recommended P fertilizer applied by seedling dipping, and T7 - seedling dipping in soil slurry without P.

In the treatments T3, T4, T5, T6 and T7, the N and K fertilizers were broadcasted at the dosages recommended by DOA, while only P fertilizer in these treatments was applied as seedling dipping in P slurry for one hour. For making the P slurry, TSP fertilizer was ground into dust and mixed with fertile paddy soil by adding water. Same amount of paddy soil and water were taken to prepare slurry only treatment (T7).

Rice seedlings were grown on parachute tray containing paddy soils for 14 days before imposing treatments and transplanting. Grain yield was measured at 14% moisture content. Third leaf from the top of the plants at the maximum tillering stage was sampled to analyze P concentration in the leaf. Twenty leaves were taken from each plot. Leaf samples were digested by di-acid mixture (HNO 3:HClO 4) at 9:4 ratio (v/v). Readings were taken by using Helios Omega UV/visible Spectrophotometer. The SAS computer software package was used to perform ANOVA.

RESULTS AND DISCUSSION

At initial available phosphorus content of the soil was 5.49 + 0.60 mg/ka. This soil was considered as P-deficient (below 5 mg available P/kg soil). The results of the study carried out in 2015/16 Maha season showed that soaking/dipping rice seedling in P fertilizer slurry before transplanting increased the grain yield in the P-deficient soil. Table 1 shows that the grain yield (t/ha) and plant P contents of the plots treated with different

137 SEEDLING DIPPING FOR PHOSPHORUS FERTILIZATION IN RICE

rates of P fertilizer and application method. The highest grain yield was obtained from the plots treated with the recommended rate of P fertilizer applied using the seedling dipping method, followed by those that received % of recommended P fertilizer applied using the same method. These results confirmed that the rice seedlings soaked/dipped in P-soil slurry have efficiently used P than when P fertilizer was broadcasted. In addition, % of the recommended P fertilizer applied using the dipping technique resulted in a higher grain yield than when the total amount of P was broadcasting. The results clearly indicated that the method of P application affects the P utilization efficiency of rice plants thus affecting the grain yield.

Table 1: Rice grain yield (t /ha) and plant P contents of the plots treated with different rates of P fertilizer and P application method. Plant P contents Treatments Grain Yield (t/ha) (%) T1 - No fertilizer 1.99 d + 0.07 0.26 ab + 0.007 T2 - P fertilizer applied by broadcasting (DOA recommendation) 2.54 bc + 0.15 0.27 ab + 0.018 T3 - P fertilizer applied by seedling dipping method (P recommended by DOA) 3.01 a + 0.20 0.28 a + 0.005 T4 - % of DOA recommended P fertilizer (Seedling dipping method) 2.79 ab + 0.19 0.24 ab + 0.006 T5 - lA of DOA recommended P fertilizer (Seedling dipping method) 2.54 bc + 0.14 0.24 ab + 0.001 T6 - % of DOA recommended P fertilizer (Seedling dipping method) 2.19 dc + 0.21 0.25 ab + 0.022 T7 - No P fertilizer (Seedling dipping in soil slurry without P) 2.003 d + 0.02 0.25 ab + 0.001 CV 8.45 7.17 Note: Within a column, means followed by the same letter are not significantly different at p=0.05.

During the early growth stages, the rice plant requires more P, but available P from soil solution cannot meet the plant requirement at this stage. Therefore, enhancing access to available P by seedling soaking/dipping would increase root development, tillering, and in turn grain yield, especially in P-deficient soils (De Datta et al, 1990). Katyal (1978) has shown that dipping seedling roots may provide 40-60% saving on P fertilizer for maintaining the same yield. Our study also revealed that applying 50% of the P recommendation made by the DOA by using seedling soaking/dipping method produced similar yield to that when the DOA recommendation was applied by broadcasting. The results clearly suggested that seedling soaking/dipping method employed in this study would save 50% P fertilizer while maintaining similar rice yields.

138 WICKRAMASINGHE et al. The P content of the leaf was significantly different (p<0.05) with rice plants in plots under all treatments showed more than 0.2% P content in the leaf. Yoshida (1976) provided a list of critical concentrations of various elements and suggested a P content of 0.1% in the leaf blade of rice plant at tillering stage as the critical deficiency level, and 1. 0% P in the straw at the maturity stage as the toxic level. Leaf samples of this study did not showed any P deficiency. The highest P content in the leaves was shown in plants under T3 (DOA recommended P fertilizer supplied by seedling dipping method). Phosphorus stimulates both root and shoot development and promotes flowering and grain development. Hence, higher P content in the leaf would improve the yield.

CONCLUSION

Seedling soaking/dipping method used in this study improved growth and yield of rice in a P-deficient soil compared to the P broadcasting method. The amount of P recommended by the Department of Agriculture can be reduced by 25-50% by using the seedling soaking/dipping method without a significant yield loss compared to applying full amount of P by broadcasting. Further testing of this method is suggested prior to making recommendations.

REFERENCES

Bandara J. M.R.S., H.V.P. Wijewardana, J. Liyanage, M.A. Upul, J.M.U. Bandara, 2010. Chronic renal failure in Sri Lanka caused by elevated dietary cadmium: Trojan horse of the green revolution. Toxical Letters 198: 33. Bangladesh Rice Research Institute (BRRI), 1997. Annual Internal Review report for 1996, Soil Science Division. Bangladesh Rice research Institute, Gazipur, Bangladesh, pp: 5-24. De Datta S.K., T.K. Biswas, C. Charoenchamratcheep, 1996. Phosphorus requirement and management for lowland rice. In: Phosphorus requirements for sustainable agriculture in Asia and Oceania - Proceeding of a Symposium 6-10 March, 1989, IRRI: 307-322. Fukuda M., F. Nagumo, S. Nakamura and S.Tobita, 2012. Alternative fertilizer utilizing methods for sustain low input agriculture. Soil fertility. [On line]. [Accessed on 12.01.2016]. Available at www.intechopen.com/books/soil . Katyal J.C., 1978. Management of phosphorus in lowland rice. Phosphorus Agric.,73: 21-34. Khan A.A., G. Jilani, S. M. Akhtar, S.M.S. Naqvi, M. Rasheed, 2009. Phosphorus solubilising bacteria: occurrence, mechanisms and their role in crop production. Journal of Agriculture Biology Science. 1(1):48-58. Kendaragama K.M.A., K.M. Senevirathne Banda and P.T. Bandara, 2003. Influence of rice crop on soil phosphorus availability in relation to phosphate fertilizer application. Annals of the Sri Lanka Department of Agriculture. 5:129-139. Sahrawat, K.L., M.P. Jones and S. Diattta, 1996. Phosphorus, calcium and magnesium fertilization effects on upland rice in an ultisol. Communication in soil science and plant analysis, 27: 2017-2023. Yoshida, S., D.A. Forno, J.H. Cocke and K.A. Gomez, 1976. Laboratory Manual for physiological studies of Rice. Los Banos. Short Communication

Annals of Sri Lanka Department of Agriculture 2016. 18: 139 - 143 EVALUATIONOF FRUITING ABILITY AND FRUIT QUALITY THROUGH DIFFERENT TRAINING SYSTEMS OF APPLE

E.K.E.C. NAYANA, D.M.R. DASSANAYAKE, Y.L.B. PAVITHTHRANI AND M.A.L.N. MALLAWAARACHCHI

Regional Agriculture Research and Development Centre, Bandarawela, Sri Lanka

INTRODUCTION

Apple is a popular fruit crop among Sri Lankans which is supplied mainly through importation at a huge expense of foreign exchange. In year 2103 alone, rupees 1.8 billion were spent for importation (AgStat, 2013). Imported fruits with harmful chemicals that are being used for long shelf life is the major issue of faced by Sri Lankan in consuming this fruit. There are some Apple ( Malus domestica ) trees cultivated in a few home gardens in Up Country Intermediate Zone (UPIC) and Up Country Wet Zone (UCWZ) in Sri Lanka. Climatic conditions in both these agro-climatic zones are conducive for flowering and fruit bearing of apple. However, the pruning systems used is not appropriate to obtain quality fruits and an economical yield. Most commonly used tree pruning types are Centre leader and Centre open approach. Hence, new training types and agronomic practices are required to increase the productivity of Apple trees in Sri Lanka. Therefore, this study was carried out to evaluate fruiting ability in UCIZ through different training systems of Apple.

MATERIAL AND METHODS

The experiment was conducted at the Regional Agriculture Research and Development Centre (RARDC), Bandarawela from August 2012 to June 2013. The experiment was carried out with six years old Apple trees with 4.5 x 4 m spacing. Selected trees for which treatments were imposed has been subject to Centre open pruning. The crop management practices were done according to the DOA recommendations. In the experiment, treatments were taken as Centre open pruning + branches angle 45 0 - 60 0 from vertical (T1), Centre open pruning + excess flowers thinning (T2), Centre open pruning + branches angle 45 0 - 60 0 from vertical + excess flowers thinning (T3) and Centre open pruning (T4) as a control were laid out in a Randomized Completely Block Design (RCBD) with four replicates. Data recording was

140 NAYANA et al. started from the beginning of flower blooming and continued up to fruit maturity. Aforesaid tree training methods were started at the vegetative stage of the tree.

Fruit quality parameters such as fruit weight, firmness, pH and Brix (TSS) were also measured in the horticulture laboratory. The experiment was arranged according to a Completely Randomized Design (CRD) with four replicates. Data were subjected to ANOVA procedure to obtain treatment means using SAS 9.1.3 statistical software. The statistical differences among treatment means were tested by DUNCAN procedure (P=0.05) test. Sensory evaluation was done by panelist’s evaluation of Apple fruits. The parameters of taste, colour and mouth feel (crispiness) were evaluated. Ten numbers of panelists were involved in the sensory evaluation. Data were analyzed using SPSS statistical software.

RESULTS AND DISCUSSION Flower blooms and fruit let count At the beginning of the reproductive stage of tree, flower blooms were counted according to the as per the Table 1. Highest mean value of number of flower blooms was recorded in control (T4). The lowest mean value of number of flower blooms was recorded in T3. However, flower blooms count was not significantly different within treatments. Fruitlets count also showed the lowest mean value in T3. Fruitlets setting were same in T1 and T2. When comparing Table 1 and Table 2, treatment 1 showed a failure in fruit set due to the wind damage or problem regarding pollination. However, fruitlet development was not significantly different in between treatments.

Table 1. Flower blooms fruitlets initiated as affected by different p lant training systems. Treatment Mean value of number of flower Mean value of number of fruit lets per plant T1 11.3 a 2.6b T2 7.0a 2.6b T3 6.6a 0.3b T4 11.6a 4.0a CV (%) 12.7 11.3 Note: Means followed by the same letter in each column are not significantly different at p=0.05

The significantly higher fruitlets formation in trees without use of any training system was recorded in flower blooms as well. The lowest mean fruitlets count was also evident T3. Fruitlets setting were same in T1 and T2. However, fruitlet development was not significantly different between treatments. Table 2 shows the mean value of fruit yield of Apple from maturity stage to harvesting stage. Highest fruit yield was recorded in plants without use of any training systems. Lowest fruit yield was recorded in Treatment 3. Fruit yield also not significantly different within treatments.

EVALUATION OF FRUIT QUALITY OF APPLE DUE TO TRAINING SYSTEMS 141 Table 2. Apple fruit yield from maturity stage to harvesting stage as affected by different training systems. Treatment Mean value of number of fruits per plant Mean value of number of fruits per (May 2013) plant (June 2013) T1 2a 1.3a T2 1a 1.0a T3 0a 0.0a T4 3a 2.3a CV (%) 26.9 24.6 Note: Means followed by the same letter in each column are not significantly different at p=0.05

According to the literature, Apple fruit yield can be improved using above training practices in European countries. Temperate countries utilize these strategies to optimize fruit yield through efficient use of sunlight for photosynthesis with correct position of limbs. Because it determines whether branches will produce primarily fruit or continue with vegetative growth. When branches grow strait up, they produce mostly vegetative parts and a very little fruits. However, in this experiment results revealed that different training systems do not significantly affect the flowering and fruiting yield of Apple in UCIZ climatic conditions in Sri Lanka.

Fruit quality Table 3 reveals that there is no significant different between treatments with any of the parameters measured in terms of quality of the fruit. In the context of TSS values of Apple fruits, highest value was evident in T3 with a comparatively low value in T4. When considering four treatments, there was a significantly different in brix values among fruits in different training systems. According to the literature, Bruce et al., (2008), reports that sugar content is changing with the different training systems of grapes. TSS formation is different with the amount of sunlight capture during the photosynthesis. The results revealed that higher sweetness can be obtained by adopting different training methods than without use of any training system.

Sensory evaluation According to the sensory evaluation results, Apple fruit taste was significantly different with each treatment. A very clear difference in taste exist from highest to lowest in a sequence of T3, T1, T2 and T4. The results revealed that training systems of branches at angle 45 0 - 60 0 from vertical, excess flowers thinning and Centre open pruning methods are important to improve the Apple fruit taste.

142 NAYANA et al. Table 3. Fruit quality parameters of Apple as affected by different plant training systems. Treatment Mean value of fruit weight Mean value of fruit Mean pH value Mean TSS value (g) firmness T1 134.4a 3.1a 2.8a 15.2a T2 129.7ab 3.4a 2.7a 14.5a T3 93.6ab 3.3a 2.6a 15.5a T4 111.1ab 3.3a 2.7a 12.8b CV (%) 14.6 4.1 2.3 11.3 Note: Means followed by the same letter in each column are not significantly different at p=0.05.

Sensory evaluation on colon of the fruit revealed that there is a significant difference between treatments. The T4 reported the significantly lowest mean value for colour (1.85). Greenish back ground with red colour was highest in T4 and other treatments were in golden colour back ground with red colour. The character of crispiness (mouth feel) of Apple fruits was significantly different between treatments. Treatments T3 and T2 reported the highest crispness. T1 and T4 were significantly lower in crispiness. Overall results revealed that the T3 has reported the highest value in taste; colour and mouth feel (crispiness). According to the literature Emily et al., (2009) has reported that flower thinning improves fruit quality by limiting number of fruits per cluster.

Table 4. Sensory evaluation of Apple with different treatment. Treatment Taste Colour Mouth feel (Crispiness) T1 3.10b 2.7a 2.1b T2 2.30c 2.55a 2.9a T3 3.55a 2.9a 3.2a T4 1.05d 1.85b 1.8b CV% 10.2 8.3 6.8 Note: Means followed by the same letter in each column are not significantly different at p=0.05

CONCLUSION

Based on the results it can be concluded that only plant pruning is sufficient to increase the yield of Apple trees in the UCIZ of Sri Lanka. However, adoption of additional plant training systems can improve the fruit quality of Apple REFERENCES

AgStat. 2012.Pocket book of Agricultural Statistics. Volume X. Socio-Economic and Planning Centre, Department of Agriculture, Peradeniya, Sri Lanka. 42p. Bruce, W.Z., K.W. Tony, L. Pelanne, M.K. Miller and S.S. Birkenmaier 2008.Effect of vertical Shoot -Positioned, Smart Designed and Geneva Double - Curtain Training Systems on Viognier Grape and Wine Composition. Emily, E.H., E.S. Tepe and D. Foulk 2009. Growing Apples in the home garden, University of Minnesota. Pp. 27-28.

Annals of Sri Lanka Department of Agriculture 2016. 18: 143 - 114

Short Communication

ASSESSMENT OF MOST POPULAR THREE MONTHS AGE RICE VARIETIES FOR ZINC (Zn) ACCUMULATION IN BROWN RICE

D. N. SIRISENA, W. M. N. WANNINAYAKE, S. S. S. WERALUGOLLA

AND A.G. S. D. SILVA

Rice Research and Development Institute, Batalagoda, Ibbagamuwa

INTRODUCTION Zinc (Zn) malnutrition affects over three billion people worldwide, mostly in developing countries (Sperotto, et al., 2010). To overcome the above problem, food fortification has been recommended as one of the approaches (Mehansho, 2006). Since rice is a staple food, bio fortification of rice with Zn is the easiest way to improve the Zn nutrition requirement of human beings. In addition to agronomical management, selecting genotypes with high efficiency of Zn accumulation even under low Zn condition and partition into grain have been identified as a reliable way to find out the most suitable variety for bio fortification (Prom-u-thai et al ., 2006). Rice samples of brown rice and milled rice were evaluated for Zn during 2006 - 2008 by Martinez et al. (2010) and found that brown rice contained 20 - 25 mg/kg Zn while milled rice had 16 - 17 mg/kg Zn. According to Martinez et al. (2010), micronutrient dense cultivars can be selected from exiting germplasm or can be generated through genetic modification. Plant breeders need to identify donor parents carrying the target traits for high Zn. Around 75 % of the total Zn was reported to be present in the endosperm of brown rice (Jiang et al., 2008). As such, Zhang et al. (2005) showed that single grain selection of narrow grains of rice tends to increase content of Zn. The objectives of the present study were to screen 3 months age most popular recommended rice varieties for Zn content in their brown rice and to determine the relationship between Zn content with grain weight.

MATERIALS AND METHODS

A field study was conducted during 2014 Yala season at the Rice Research and Development Institute (RRDI), Bathalagoda, located in the low country intermediate zone, IL1, agro-ecological region (latitudes 7° and 8°, longitude 80° and 81°and at an elevation of 65 m above mean sea level). Soil of the site belongs to Kurunegala series which characterized as Red Yellow Podzolic soil great soil group (Wickramasinghe, 2005). To maintain the uniformity of the Zn in all plots, field maintained without applying any sort of organic or inorganic fertilizer for four decades was selected. Most commonly grown and popular seven, three month age recommended rice varieties (Bg 300, At 303, Bg 304, Bg 305, At 306, At 307, Bg 310) were selected. Plots, size 6 m x 3

144 SIRISENA et al. m, were arranged in accordance with Randomized Complete Block Design (RCBD) and treatments were replicated three times. Seventeen days old seedlings were transplanted in the field as one seedling per hill at the spacing of 15 cm x15 cm. During the whole cultivation period pest or disease damages could not be observed at harmful level. During the cropping period no any kind of fertilizers or manure were added. Hand weeding was done to control weeds. Before crop establishment, two composite soil samples were obtained from the field using a soil auger. Samples were air dried, crushed and sieved through 2 mm sieve.

Extractable Zn content in the soil was determined using DPTA (Diethylene Triaminepenta Acetic Acid) method by atomic absorption spectrophotometer (AAS). At the time of harvesting, 5 plants were collected randomly from each plot and seeds were separated from panicles by hand. Collected seed samples were air dried and kept in oven for 3 days under 70 oC for oven drying. Oven dried seed samples were de-husked to separate grain and husk. Grains were ground to obtain powdered samples. Before using the ground samples for analysis they were oven dried overnight at 70 oC. Care was taken to wash and clean all equipment with tap water and then with distilled water before using them. Samples were digested using double acid (one volume of perchloric acid

(approximately 60 % m/m HClO 4) to four volume of nitric acid (approximately 70 % m/m HNO 3) were mixed and digested samples were analyzed for available Zn concentrations using AAS. Treatment mean differences were evaluated by Duncan Multiple Range Test (DMRT) mean separation test at a=0.05.

RESULTS AND DISCUSSION

Extractable Zn content in the soil at the time of planting was 0.39 ± 0.01 mg/kg. This value was far below the critical level of 1 mg/kg reported by Bandara et al. (2005). Therefore, cultivating rice at this Zn level will help to select the best varieties which have the capacity to absorb and accumulate Zn in rice grain under low available Zn condition. Zn concentration in grain of all 7 rice varieties ranged from 24.6 mg/kg to 31.8 mg/kg. According to Chandel et al. (2010) there is a significant variation among rice varieties for their Zn content in grains. Proving the above finding, the highest Zn content of 31.8 was reported from long slender rice variety At 306 and followed by At 307 (Figure 1). These

POPULAR 3 MONTHS VARIETY FOR ZINC ACCUMULATION IN BROWN RICE 145 results show the significant genetic diversity or variation in the 3 months age rice germplasm on accumulation of Zn in brown rice. According to Welch and Graham (2004), Zn content in rice varieties vary from

Figure 1. Zn content in brown rice of seven rice varieties. absorption, translocation and transport within the plant. Results appeared in the Figure 2 revealed that though the relationship between seed weight and Zn content in brown rice has a positive trend but the relationship was not significant (R 2 = 0.23).

35 30 y = 0.5839x + 13.552 25 + R2 = 0.2361 20 ______-*■ 15 ♦ >r ------♦ ♦ 10 5 0

-I ------1 ------1 ------1 ------1 ------1 15 17 19 21 23 25 27 Seed weight

Figure 2. Relationship between seed weight and Zn content in brown rice.

CONCLUSION

The level of Zn varied from 24.6 to 31.4 mg/kg and the highest value was recorded from At 306 while Bg 310 had the lowest. Since there is a varietal difference affecting Zn accumulation in grain, whole rice germplasm should be tested for Zn accumulation in brown rice to find out most suitable variety for bio-fortification and relationship of Zn with seed shape should also be examined to determine the donor parents for future breeding programmes.

146 SIRISENA et al. REFERNACES

Banadara, W. J., D. Kumaragamage, D. B. Wickramasinghe, S.B.A, Weerawarna, 2005. Site specific nutrient management strategy to increase rice yields in Low country intermediate zone. Journal of the Soil Science Society of Sri Lanka. 17: 22-44 Bouis H.E., R. M. Welch, 2010. Biofortification - a sustainable agricultural strategy for reducing micronutrient malnutrition in the global south. Crop Science 50: 20-32 Chandel G., S. Baneree, S. See, R. Meena, D. J. Sharma and S. B. Verulkar. 2010. Effects of diffrent nitrogen fertilizer levels and Native Soil properties on rice grain Fe, Zn and portein content Riceb Science 17: 213 - 227. Jiang, W., P.C. Struik, H. Van Keulen, M. Zhao, L.N. Jin and T.J. Stomph. 2008. Does increased zinc uptake enhance grain zinc mass concentration in rice? Ann Appl Biol 53:135-47 ITI, 2011. Properties of some traditional rice varieties of Sri Lanka. pp 56 Mehansho, H. 2006. Iron fortification technology development: New Approaches. J Nutr 136: 1059-1063 Promthai, C., B. Dell, G. Thompson and B. Rerkasem. 2003. Easy and rapid detection of iron and Zn in rice grain. Sci. Asia. 29: 203. Sellapan, K., K. Datta, V. Parkhi and S.K. Datta. 2009. Rice caryopsis structure in relation to distribution of micronutrients (iron, zinc, b-carotene) of rice cultivars including transgenic indicia rice Plant Sci. 177: 557 - 562. Welch, R.M. and R.D. Graham, 2004. Breeding for micronutrient in staple food crop from a human nutrition perspective J. Exp. Bot. 55: 353 - 64 Welch, R.M. 1986. Effects of nutrient deficiencies on seed production and quality. Adv. Plant. Nut. 2: 205- 247. Wickramasinghe, W.M.A.D.B. 2005. Management of Intermediate Zones soils for rice. In Soils of the Intermediate Zones of Sri Lanka. Eds. R.B. Mapa, A.R. Dissanayake and H.B. Nayakakorale. Soil Science Society of Sri Lanka, Special publication No. 4 Sarvodaya, Vishva Lekha. pp 191-196. Zhang, M.W., B.J. Guo, and Z.M. Peng. 2005. Genetic effects on grain charateristics of indica black rice and their uses on indirect selection for some mineral element content in grains. Genet. Resour. Crop. Ev. 52: 1121 - 1128.

Annals of Sri Lanka Department of Agriculture 2016. 18: 147 - 114

Short Communication

INFLUENCE OF VARIETAL DIFFERENCES ON SENSORY QUALITIES OF LOCAL RICE-BASED FOOD PRODUCTS

R. J. RATHNAYAKE, D. K. PADMALATHA AND K.M.K. KUMARIHAMY

Rice Research & Development Institute, Batalagoda, Ibbagamuwa, Sri Lanka

INTRODUCTION Sri Lanka has achieved the self-sufficiency in its staple food, rice and there had been surplus production in rice during some seasons especially when the weather conditions are favourable (Central Bank, 2008). Rice is a high-carbohydrate, rich in quality protein (Biological Value =86%) is higher than that of whole wheat (BV=53%) or corn (BV=49%) and good source of vitamins and minerals such as thiamine, niacin, riboflavin, iron, calcium. ( http://www.fao.org.com , http://nutritondata.self.com ). Rice can compete with wheat for it is nutritional quality (Adair, 1972). Starch is the main composition of rice grain and used in food industry. Many of the cooking and eating characteristics of milled rice are influenced by the ratio of Amylose and Amylopectein (SanjivaRao et al, 1952). Even though rice flour cannot be used as raised (leavened) baked products because it does not contain gluten (Deobald, 1972), it’s possible to use it for preparation of non-leavened food such as Milk rice, Pittu, hoppers, string hoppers and Kokis. The composition of rice flour varies according to the variety used and it affects the quality of rice-based products. Therefore, identification of suitable varieties for rice- based food products is very important. This study has been carried out at Rice Research & Development Institute (RRDI), Batalagoda, Sri Lanka to compare the quality of local rice-based food products with six recommended rice varieties.

MATERIAS AND METHOD

The paddy samples were collected from six popular rice varieties, namely, Bg 300, Bg 352, Bg 358, Bg 360, Bg 94-1 and Bg 403 during 2007 Yala season. After three months period, the samples were de-hulled in Satake sample dehuller and milled in a Mac gill sample mill. Preparation of milk rice: 500 g of milled rice of each variety were cooked with using sufficient amount of water and small amount of salt (equal for all) and 260 ml of coconut milk (equal for all) were added and mixed well. Then, Milk rice was prepared.

Preparation of pittu: 250 g of milled rice samples of each variety were soaked in 4 hours in normal water. It were drained off and ground. The resulting rice flour was mixed with 200 g of scraped coconut, small amount of salt (equal for all) and needed amount of water. Then the small (Pittu) particles were made by smooth mixing by hand. The

148 RATHNAYAKE et al. prepared raw Pittu were steamed by using steamers for 10 minutes.

Preparation of hoppers: 250g of milled rice samples from each variety were soaked in normal water for 6 hours. It were drained off and ground in Smith sample grinder. The resulting wet rice flour was mixed with 1 tea spoon of yeast, 200 ml of coconut-water, and small amount of salt (equal for all). It was kept for 12 hours for fermentation. Then 80ml of coconut milk was added, mixed well and was kept 2-3 hours to settle. Thereafter, the hoppers were made using above mixture.

Preparation of string hoppers: 250 g of milled rice sample from each variety was soaked in normal water for 6 hours. It was drained and ground to fine particles using Smith sample grinder. The resulting wet rice flour was roasted. The roasted rice flour was mixed with 200 ml of warm water and small amount of salt (equal for all) and mixed well. Then, strings hoppers were made using hand cutter and were steamed for 15 minutes.

Preparation of kokis: 250g of milled rice samples of each variety were soaked for 6 hours. It was drain off and ground in Smith sample grinder. The resulting wet rice flour was mixed with of 200g of coconut-milk, small amount of salt, small amount of turmeric powder (equal for all), water (needed amount) and mixed well. Then, kokis were made and pried using hand cutter in deep oil.

Sensory Evaluation: Untrained sensory panel (30 members of staff of RRDI, Batalagoda) was used to evaluate sensory quality parameters of prepared local rice-based food products. Taste, Appearance, Aroma, and Mouth feel were evaluated as sensory quality parameters. Scales of above parameters are 1= Weak (W), 2 = Moderate (M), 3 = Good (G), 4 =Very good (V), 5= Excellent (E). RESULTS AND DISCUSSION

According to statistical analysis of data, (Friedman test), there are significant differences of preference for each sensory parameter of Milk rice, Pittu, hoppers, string hoppers, Kokis such as Taste, Aroma, Appearance and Mouth feel among different varieties tested.

Milk rice: All varieties except the Bg 360 showed a better performance for Appearance. Bg 352, and Bg 94-1 resulted in with maximum score for taste. Bg 352, Bg 300, Bg 941 scored relatively high values for Mouth-feel. Bg 360 did not perform well for all parameters tested. None of the varieties performed well in the context of Aroma. However, the sequence of combination of overall preference of those varieties for Milk- rice are Bg 300 > Bg 94-1> Bg 352> Bg 358> Bg 360.

Pittu: Bg 352 resulted with better performance for taste than other varieties. Bg 360, Bg

INFLUENCE OF VARIETY ON QUALITY RICE -BASED PRODUCTS 149

358 and Bg 403 have claimed maximum scores for appearance. Bg 403, Bg 358, Bg 360 and Bg 352 performed well in terms of Mouth-feel. All varieties do not perform well for Aroma. However the sequence of combination of overall preference of tested varieties for Pittu are Bg360 >Bg 403>Bg352>Bg 358>Bg 94-1>Bg 300.

Hoppers: Bg 403 showed highest performance for most of the parameters of hoppers than other varieties. Bg 300 also has got sufficient score for most of the parameters except Aroma. Among these six varieties Bg 360 resulted lowest score for overall preferences. The sequence of combination of Overall preference of those varieties are Bg 403> Bg 300>Bg 358>Bg 352>Bg 94-1>Bg 360.

String hoppers: Bg 403 shows the best performance for all parameters except Aroma than other varieties. Bg 300 also has got higher score for Mouth-feel and Appearance. Bg 352 also has got sufficient scores for appearance. But other parameters are not favourable. All varieties did not show better performance for Aroma. The sequence of combination of Overall preferences of those varieties are Bg 403> Bg 300>Bg 358> Bg352>Bg 94-1>Bg 360.

Kokis: Bg 360 and Bg 358 showed better performance for Taste than other varieties. Bg 352 and Bg 300 have got maximum scores for Mouth-feel. Bg 300, Bg 352, Bg 358 and Bg 94-1 have resulted reasonable scores for appear ance. AH var ieti es did not result better performance for Aroma. The sequence of combination of Overall preference of those varieties for Kokis are Bg 352>Bg 300>Bg 358>Bg 94-1>Bg 360>Bg 403 CONCLUSION

There is a significant difference in sensory quality characteristics between varieties and local rice food products. According to preference of majority of people, it can be concluded that suitable varieties for local rice-based food products as fallows; Milk rice from Bg 300, Bg 94-1, Pittu from Bg 360, Bg 403, hoppers from Bg 403, Bg 300, string hoppers from Bg 403, Bg 300, and Kokis from Bg 352, Bg 300. It was also found that majority of people did not like food products made out Bg 360 except Pittu.

REFERENCE

Adair, C. R., 1972. Production and utilization of rice in Rice Chemistry Technology. Ed. D.F. Houston, A monograph series. American Association of Cereal Chemistry.1-15pp. Central Bank Report. 2008. Department of Census and Statistics, Sri-Lanka. Deobald, H.J. 1972. Rice flour in Rice Chemistry and Technology. Ed. D.F. Houston. A monograph series. American Association of Cereal Chemistry http://nutritiondata.self.com Sanjiva Rao, B., A.R. Vasudeva and R.S. Subrahmanya. 1952. The Amylose and Amylopectin content of rice and their influence on the cooking quality of cereals. Proc. Indian Acad.Sci.70-80pp.

Annals of Sri Lanka Department of Agriculture 2016. 18: 150 - 114

Short Communication

VALIDATION OF AGRICULTURAL PRODUCTION SYSTEMS SIMULATOR MODEL FOR MUNG BEAN [VIGNA RADIATA (L.) R. WILCZEK] IN THE DRY ZONE OF SRI LANKA

W.M.N.D. GUNATHILAKA 1, R.P.R.K. AMARASINGHA 2 AND U.I.P. PERERA 1

1 Grain Legumes & Oil Crops Research & Development Centre, Angunakolapellessa, Sri Lanka 2 Postgraduate Institute of Agriculture, University of Peradeniya, Sri Lanka

INTRODUCTION

Mung bean [Vigna radiata (L.) R. Wilczek] is an important pulse crop grown in Sri Lanka under traditional farming system mainly in the dry and intermediate zones. Mung bean is a vital source of vegetable protein, vitamin and minerals particularly in developing countries. It is a short duration legume, hence grown as sole crop as well as inter and multiple cropping systems under rainfed and irrigated conditions and increases farmer income and improves the soil fertility through symbiotic nitrogen fixation (Malik, 1994). In Sri Lanka, mungbean is cultivated about 11,840 ha and annual production is about 14,352 mt (Agstat, 2014). The importation of mung bean in the year 2014 was 5,075 mt and amount of export was 2,973 mt, which shows the production is insufficient for the country. Among all other field crops, mung bean recorded the highest wholesale and retail price in Sri Lanka. Therefore, mung bean is considered as a valuable other field crop in Sri Lanka. Simulation models are useful tools to assess the performance of agricultural systems under different scenarios. The Agricultural Production Systems Simulator (APSIM) is a farming systems model that simulates the effects of environmental variables and diverse management decisions on production (crops, pasture, trees, and livestock), profits, and soil condition (Keating et al, 2003). The model can be used to analyze risks and explore alternative management options such as irrigation management, crop choice, planting date, and fertilizer rate using local climate and farm-specific soil data. The present study was conducted to testing and validate APSIM model in the Dry Zone of Sri Lanka for mung bean.

MATERIALS AND METHODS

Parametrization of mungbean module in APSIM The APSIM-mung bean module in APSIM version 7.5 was used to parameterize the phenology and growth of mung bean variety, MI 6. Required phenology and growth data for MI6 data for were collected from the available literature (Amarasingha et al, 2016).

Model testing and validation Study area: The APSIM mung bean module testing and validation were done at the Angunakolapelessa (Lat:6 ° 90” Log:80°54”), Aranaganwila (Lat 7°57”: Log:81°16” )

VALIDATION OF SIMULATOR MODEL FOR MUNG BEAN IN THE DRY ZONE 151 and Mahailluppallama (MI) (Lat: 8° 00”E: Log: 8°02”N). Soil data: Soil physical and chemical properties were collected from the fact sheets of benchmark soils of the Dry Zone of Sri Lanka published by the soil science society of Sri Lanka (Mapa et al, 2010). Weather data: Daily weather data from January 2013 to December 2015 were collected from the Grain Legumes and Oil Crops Research and Development Centre Angunakolapalassa Field crops Research and Development Institute, Mahailluppallama and Regional Agricultural Station, Aralaganwila were used for the simulation. Maximum and minimum temperatures, rainfall and sunshine hours were available on a daily basis. Daily incoming radiation (MJ/m 2) was calculated using sunshine hours and location specific information such as latitude and longitude, solar elevation and angstrom coefficients.

Model testing Crop and management data: The primary data collected from Angunakolapellessa, secondary data collected from Field crops Research and Development Institute, Mahailluppallama and Regional Agricultural Station, Aralaganwila on planting date and yield were used to test the model. Crop management strategies were adjusted in the model simulations as collected from the field trials which are followed by the Recommendations of the Department of Agriculture. The simulated yields were used to compare the observed and predicted values once simulated using the appropriate weather data.

Model validation Crop yields collected from published literature (secondary data) were used to validate the model both qualitatively (graphical) and quantitatively (statistical). The zero origin (1:1) graphs of the relationship between model simulated and field observed data (field measured data) were plotted to identify the difference/similarity between predicted and observed values. The statistical expressions were used for comparing the simulated and field measured data were average error basis (AE), coefficient of variance (CV), root mean square error (RMSE) and co efficiency of residual mass (CRM) presented as:

Coefficient of Variance (CV) = 100 X 0 m 0.5 Root Mean Square Error (RMSE) ■ V” f 152 GUNATHILAKA et al. >i= l' where Pt is simulated values; Ot is measured values; Om is mean of measured values and n is number of the observation.

RESULTS AND DISCUSSION

The APSIM could simulate the observed mung bean yields with a coefficient of determination of 0.97 and co-efficiency of variation of 6.9%. Therefore, the parameterised and validated APSIM model is strong. Department of Agriculture annually conduct large number of yield trials such as PYT, MYT, NCVT and VAT under their varietal releasing programmes. Therefore, models such as this can be used in evaluating the performance of mung bean in different locations and seasons under diverse management conditions.

Figure 1: Observed and simulated yield for variety MI 6 mung bean varieties grown during Yala (unfilled) and Maha (filled) season in Mahailluppallama (squares), Angunakolapelessa (circles) and Aralaganwila (triangular). CONCLUSION

With these results APSIM model can be suggested as a tool to forecast yield of mung bean variety MI6 and could be applied for other field crops such as maize. After model testing and validation for each crop and variety without conducting on farm trials and it would shorten the time of releasing a variety.

VALIDATION OF SIMULATOR MODEL FOR MUNG BEAN IN THE DRY ZONE 153 ACKNOWLEDGEMENT

The authors are greatly acknowledge AusAID-CSIRO project on “Improve climate forecasting to enhance food security in Indian Ocean rim countries (AUSAID Agreement 59553) through the Agriculture Education Unit (AEU) of the Faculty of Agriculture ,University of Peradeniya, Sri Lanka and Miss Priyanthi Kumararathne, ADA (Research) Field Research and Development Institute, Mahailluppallama, Miss Chandrika Hitinayaka (ADA Research), Regional Agricultural Station, Aralaganwila, Punya Delpitiya (ADA Research) for the supplying of data.

REFERENCES

Agstat. 2015. Pocket book of Agriculture Statistics. Socio economics and planning Center, Department of Agriculture Sri Lanka. Amarasinhga, R.P.R.K., Suriyagoda, L.D.B., Marambe, B., Galagedara, L.W. Silva, G.L.L.P., Punyawardena, R., Nidumolu, U., and Howden, M. 2014. Improving water productivity in moisture limited rice based cropping system: A modelling approach to select the best crop combinations. Agriculture Water Management 160: 2015 July, DOI: 10.1016/j.agwat.2015.07.001 Malik B.A. 1994. Grain legumes. In: Crop Production. (Ed.): M.S. Nazir. National Book Foundation, Islamabad. P. 301. Mapa, R.B., Somasiri, S. and Dassanayake, A.R. 2010. Soils of the dry zone of Sri Lanka. Special Publication No. 7, Soil Science Society of Sri Lanka. Keating, B.A., Carberry, P.S., Hammer, G.L., Probert, M.E., Robertsona, M.J., Holzwortha, D., Hutha, N.I., Hargreaves, J.N.G., Meinke, H., Hochmana, Z., mcleanb, G., Verburgc, K., Snowc, V., Dimes, J.P., Silburne, M., Wang, E., Browna, S., Bristowc, K.L., Asseng, S., Chapmanb, S., Mccowna, R.L., reebairne, D.M.C., Smith, J. (2003). An overview of APSIM, a model designed for farming systems simulation. European Journal of Agronomy. 18, 267-288.

Annals of Sri Lanka Department of Agriculture 2016. 18: 154 - 143

Short Communication

ASSESSMENT OF PESTICIDE USAGE IN LEAFY VEGETABLE FARMING IN MATARA DISTRCT

G.C. PRASADI 1 AND D.L. WATHUGALA 2

1 Agricultural Research Station, Thelijjawila, Sri Lanka 2 Department of Crop Science, Faculty of Agriculture, University of Ruhuna, Sri Lanka

INTRODUCTION

Low country vegetable cultivation is most popular among the farmers of Southern Province in Sri Lanka. Brinjal, luffa, snake gourd, bitter gourd, and leafy vegetables are the major vegetable crops cultivated in the area. The use of high-yielding varieties, inorganic pesticides and fertilizers has led to a significant increase in agricultural production. The climatic conditions of the Matara district combined with high yielding varieties of crops and the increase use of chemical pesticides have resulted in a conducive environment for development and multiplication of pests and diseases (Aheeyar et al., 2014). However, indiscriminate use of agro chemicals, especially chemical pesticides has caused negative externalities such as health hazards to human and other beneficial organisms, pollution of the environment and water, build up of insect resistance to pesticides, and outbreak of secondary pests (Dutcher, 2007). Although, most of the consumers know health hazards of consuming vegetables grown by applying chemicals, they prefer healthy, succulent and fresh looking vegetables with no visible lesions or damages caused by pests or diseases. Therefore, heavy use of chemicals in vegetable cultivation is still a common problem. Meanwhile, the use of agrochemicals including pesticides has been recognized as an easy and cheap way to produce unblemished vegetables and attain increased farm productivity. There is a disagreement among scientists about the contribution of pesticides to crop production (e.g., reducing losses) and the negative impacts of their use on the environment and human health (Aheeyar et al., 2014).

Generally, farmers are lack of knowledge about proper pesticide management, including safe handling and storage of pesticides. While studies on productivity of pesticides are relatively common only a few studies has assessed pesticide use pattern of the farmers. However, there are no recent comprehensive studies on the socio-economic impacts of the use of chemical pesticides on leafy vegetables in Matara district. Therefore, the objective of this study was to estimate the level of pesticide usage in leafy vegetable cultivation in Matara district.

PESTICIDE USAGE IN LEAFY VEGETABLE FARMING IN MATARA DISTRCT 155 MATERIALS AND METHODS

The survey was conducted in the year 2015. Considering the resources available, a sample of 45 farmers was selected for the survey using the random sampling technique. A pre-tested, structured questionnaire was used to interview the randomly selected farmers from selected localities. Information pertaining to certain socio-economic aspects of farmers and consumers, such as family size, education level, size of land holdings, cropping pattern; details on vegetable cultivation; namely, the area under cultivation, land preparation, inputs used and the outputs obtained were collected through the questionnaire. In addition, data on prices of inputs and outputs, method of sale, handling of pesticides, awareness of farmers on the toxicity level of pesticides, safety measures adopted during applications of chemicals also collected in during harvesting period in 2014. Primary data were collected using different tools such as structured questionnaire, key informant interviews, focus group discussions, and direct field observations while published and unpublished reports were the sources of secondary data. Tabular and descriptive analysis was used to examine different socio-economic factors of the leafy vegetable farmers’ and the use of pesticides.

RESULTS AND DISCUSSION

Most of the leafy vegetable growers cannot identify harmful insects, diseases and weeds. Leafy vegetable farmers in the study area use a total of 15 commercially branded pesticides comprising 12 insecticides and three fungicides (Table 1). Almost all farmers used insecticides to control insect pests and the same is true for use of fungicides to control fungal infestation and none used herbicides to control weeds. Reason for no use of herbicides in the cultivation of leafy vegetable crops is that usually manual weeding is practiced after crop establishment in the field. Only 25 % of the farmers used biological pesticide (Neem extract) to control pests and diseases. A majority of farmers (76%) use a measuring device which accompanies the bottle of pesticides to measure the volume, but some farmers use the cap of the bottle to measure the chemical volume. About 60% of the farmers always apply pesticides as a precautionary measure prior to the appearance of any symptoms of pests or diseases, though it is needed for only selected pests and diseases. They frequently apply pesticides without considering the visual symptoms of pests and disease problems. However, 20 % of farmers apply pesticides only after appearance of the symptoms of pests or diseases.

156 PRASADI et al. Table 1 . Usage of branded pesticides in Matara district. Type of pesticide Chemical name Farmers reporting use (%) Insecticide 1. Abamectin18g/l EC 50 2. Cardosulfan 200g/l SC 34 3. Fipronil 50g/l SC 20 4. Imidacloprid 70% WG 60 5. Imidacloprid 200g/l SL 78 6. Sulphur 80%WG 30 7. Tebufenozide 200 g/l SC 20 8. Thiamethoxam 70% WS 20 9. Thiamethoxam 25% WG 80 10. Dimethoate 400g/l EC 72 11. Acetamiprid 20% SP 45 12. Chlorfluazuron 50g/l EC 65 Fungicide 1. Tebuconazole 250g/l EW 34 2. Propineb 70% WP 80 3. Mancozeb 80% WP 65

Results revealed that 15% of the farmers rely on extension officers as the first source of information to choose a pesticide for a given pest or disease. Nearly 45% of the farmers depend on their own experience as the first priority to select a suitable pesticide and another 35% of the vegetable farmers depend on pesticide dealers to select pesticides. A very few (5%) select pesticides from the information distributed through print media such as leaflets, as the first source of information. Pesticide label contains information such as recommended dosage, type of suitable crops, toxicity level, symptoms of pesticide poisoning and first aid measures to guide the user on correct and safe use of it. According to the survey results, 90 % of farmers in the sample read the instructions given in the label before use. More than 67% of the farmers did not pay attention to the expiry date of the product (shelf life).

Around 75% of the farmers are not concerned about the colour band of the pesticide they purchase. Only 27 % of the sample farmers were aware of the colour band denoted in the pesticide packs. The survey findings indicated that most of the farmers (71%) do not follow instructions on the recommended dosage of the pesticide given on the label and tend to use overdose. About 37 % of overdosing farmers believe that it is essential to overdose chemicals as pesticides available in the market do not have strength as per the specifications given in the label and also farmers apply higher dosages based on their past experience of non-effectiveness of applying the recommended dosage in controlling pests and diseases.. The survey has found that 77% of farmers store pesticide bottles in a safe location within or outside the house to make them inaccessible to children. The rest of the farmers mostly place the bottles in unsafe locations in the house without considering safety precautions. Most farmers (70%) dispose empty glass bottles with the garbage and another 15% of the farmers have sold empty glass bottles to collectors. Another 9% of the farmers have thrown their empty glass bottles in irrigation channels and outside

PESTICIDE USAGE IN LEAFY VEGETABLE FARMING IN MATARA DISTRCT 157 the house. In case of plastic bottles and polyethylene packing materials, 46% of the farmers have burned them while 37% have placed them in the garbage. Another 7% of the farmers reuse the empty plastic bottles for feeding bathing etc. of pets. However, 10 % of the farmers have thrown their empty plastic/polythene containers in the irrigation channels and outside the house without any concerns on the consequences of their actions. The majority of them wash the sprayers in the irrigation channels and reservoirs (53%) and another 47% of farmers use domestic water sources such as domestic dug-well and tap to wash sprayers.

CONCLUSION

Majority of leafy vegetable growers in Matara district are small holders and use of pesticide is the main method adopted to control pest attacks. Seventy per cent of farmers use various commercially branded pesticides but do not use herbicides for weed control. To satisfy higher demand and consumer preferences, pesticides are used prior to the economic threshold level or with the absence of attack. Most of the farmers select pesticides by their own experiences and use higher doses than recommended rates. Further, most of them follow good habits in pesticide storage, preparation, application etc. However, they do not have much concern on health and environmental issues of pesticide usage as first priority but, to maximize the profit at any environmental or health cost. Therefore, Department of Agriculture, Southern Province should initiate a comprehensive popularization programme on eco-friendly, healthy, effective and convenient methods for pest and disease control of leafy vegetable grown in Matara district.

REFERENCES

Aheeyar, M.M.M., Bandara, M.A.C.S. and Padmajani, M.T. 2014. Assessment of Pesticide Usage in upcountry vegetable farming in Sri Lanka, Hector Kobbekaduwa, Agrarian Research and Training Institute, Colombo, Available at https://www.researchgate.net /publication/264565995_Assessment_of_Pesticide_Usage_in_Up- Country _Vegetable _Farming_in_Sri_Lanka Accessed on 20 th April 2016.; Dutcher, J.D. 2007. A Review of Resurgence and Replacement Causing Pest Outbreaks in IPM, In A. Ciancio, and K. G. Mukerji (ed), General Concepts in Integrated Pest Management, Springer, The Netherlands. Food and Agriculture Organization, 2016. Pesticide, Food and Agriculture organization, Available at https://en.wikipedia.org/wiki/Pesticide Accessed on 22 nd April 2016

Annals of Sri Lanka Department of Agriculture 2016. 18:158 -164

Short Communication

EVALUATION OF FINGER MILLET GERMPLASM FOR RESISTANCE TO BLAST CAUSED BY MAGNAPORTHE GR1SEA

W.M.K. FERNANDO 1, H.N.S. FERNANDO 2, W.M.S.D.K. WIJERATHNE 1, D.M.K. DISSANAYAKE 1, W.M.R. KUMARI 1 AND D.C.M.S.I. WIJEWARDANA 1

1Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka 2Regional Rice Research and Development Centre, Bombuwela, Sri Lanka

INTRODUCTION

Finger millet (Eleusine coracana L.) is ranked as the third most important cultivated cereal in Sri Lanka. The area and annual production under finger millet in Sri Lanka were about 7,416 ha and 8,852 t in 2014, respectively (AgStat, 2015). Finger millet crop is not affected by many diseases; however the blast disease may act as a major constrain causing heavy yield losses especially during stormy weather conditions. Severe yield losses could occur due to blast. For example, 80-90% yield loss has recorded in India (Venkataryan, 1947) and up to 90% in Eastern Africa (Mgonja et al, 2007). High humidity (90% and above), 25-30 0C temperature and cloudy days with intermittent rainfall are favourable conditions for the disease (Nagaraja et al., 2007) and same climatic conditions are experiencing during certain seasons even in Sri Lanka.

Finger millet blast is caused by the fungus Magnaporthe grisea (anamorph Pyricularia grisea) and the disease appears at all stages of the crop causing leaf, neck and finger blast (Nagaraja et al., 2007). The most susceptible stage for leaf blast is seedling stage, whereas for neck and finger blast is pre-flowering stage. Typical spindle shaped spots appears on leaf lamina and then these spots enlarge, coalesce showing blasted appearance from tip to the base in leaf blast. In neck blast, pathogen attacks the culms at nodal regions showing blackening and attack at neck region results in seed sterility, undeveloped seeds and frequently hanging down of the stalk from the neck. In finger blast, fingers infect from apical portion towards the base and eventually result in shriveled and blackened seeds (Nagaraja et al., 2007).

Blast disease could be controlled by using cultural methods, chemicals and resistant varieties. But management through chemicals may result in establishment of resistant strains to these chemicals and environment threat related problems (Karthikeyan and Gnanamanickam, 2000). Hence use of resistant varieties is the most cost effective, environmental friendly, safe, convenient method of controlling disease (Barman, 1990). Hence, this experiment was carried out with the objective of identification of resistant/tolerant promising finger millet lines for blast disease.

MATERIALS AND METHODS

The experiments were conducted during Maha 2013/14 and 2014/15 seasons at the Field Crops Research and Development Institute (FCRDI), Mahailluppallama. Nine

EVALUATION OF FINGER MILLET GERMPLASM FOR RESISTANCE TO BLAST 159 finger millet accessions were screened with the recommended varieties Rawana and Oshada as susceptible and tolerant checks for finger millet blast, respectively. Finger millet blast sick plot nurseries and row seeding in a field were conducted separately. Neck blast was measured using row seeded field trial. Crushed, blast infected leaves were introduced for field trial to inoculate the pathogen. Blast nurseries were covered using polythine cover and water spraying was practiced daily to facilitate proper humidity level. Fungicides were not applied and experiments were conducted as per a randomized completely block design with three replicates. Disease Severity Index (DSI) was calculated according to the data taken Days after row seeding (DARS) in row seeded trial and Days after seeding (DAS) in nursery trial using 0-9 scale (0 - 0% , 1 - 1 to 5 % , 3 - 6 to 25 %, 5 - 26 to 50 %, 7 - 51 to 75 %, 9 - > 75 % infections in whole plant) for leaf blast. Neck blast and finger blast were calculated as percentage of disease incidence (DI) as suggested by Nagaraja et al. (2007). The CATMOD procedure in Statistical Analysis Software (SAS) was used to analyze data after carrying out the normality test.

DSI % = Total sum of numerical ratings X 100 Number of observations x Maximum disease rating

Neck blast DI % = No. of infected ears per treatment X 100 Total No. of ears per treatment

Finger blast DI % = No. of infected ears per treatment X 100 No. of fingers in five plants x Total No. of ears

RESULTS AND DISCUSSION

Normality test was run for the calculated DSI and DI using disease counts of collected in all trials. None of thed ata sets were followed a normal distribution (Shapiro - Wilk test statistics p< 0.05). Therefore non parametric approach was practiced in the SAS analysis using CATMOD procedure.

In general, all lines showed low leaf blast reactions while practicing row seeding than the blast nurseries and it may probably due to low plant density (Table 1). Results in blast nursery trials in both seasons showed that all the accessions are susceptible to leaf blast except line 11369 and check Oshadha (Table 1). Lowest DSI was recorded in Finger millet line 11369 in both seasons. The DSI of leaf blast of line 11369 was significantly lower than check variety Oshadha only in 2014/15 Maha season, but insignificant in 2013/14 Maha season.

160 FERNANDO et al. Table 1. DSI of finger millet germplasm against leaf blast. Variety/ In direct row seeding In nursery Germplasm Maha 2013/14 (42 Maha 2014/15 Maha 2013/14 Maha 2014/15 (30 DARS) (52 DARS) (24 DAS) DAS) Oshadha 28.5 a 32.6 a 46.4 a 47.0 a Rawana 72.4 A 63.7 A 72.4 A 60.0 A Line 12415 46.1 Aa 53.0 Aa 67.7 Ab 54.4 Aa Line 12263 51.1 Aa 64.1 Ab 77.8 Ab 79.5 Bb Line 12274 43.5 Aa 61.9 Aa 64.4 Ab 68.6 Ab Line 12448 47.4 Ba 61.9 Aa 69.2 Ab 53.0 Aa Line 10326 51.1 Aa 61.1 Aa 79.3 Ab 47.8 Aa Line 11352 47.4 Aa 46.7 Ba 74.8 Ab 46.7 Aa Line 11369 28.3 Ba 13.7 Bb 41.9 Ba 31.5 Bb Line 7090 52.6 Ab 64.8 Ab 66.8 Ab 65.2 Ab Line 7088 53.0 Aa 55.2 Aa 73.0 Ab 59.6 Aa Note: Within each column, upper case letter indicates comparison with susceptible check Rawana and lower case indicates comparison with tolerant check Oshadha.

Lowest DI for neck blast and finger blast also obtained from line 11369. However, it was not significantly different from Oshadha (Table 2). Cultivation of blast resistant varieties will reduce the cost of fungicides and reduce the adverse effects on health and environment. The variety Oshada is generally regarded as moderately susceptible variety for the blast disease and it is not giving good yield compared susceptible variety Rawana during Yala season. As the cultivation of susceptible varieties in rainy season is not economical due to heavy disease infestation, improving both yield and high level of disease resistance are two fundamental characters to be considered when variety is released. Even though there is no significant difference with the selected line 11369 with already released variety Oshadha, this line will be an important genetic source for future resistant breeding programme of Finger millets.

CONCLUSION

Finger millet lines 12415, 10326, 12448, 11352, 12263, 12274, 7088 and 7090 showed susceptible reactions for finger millet blast disease while Line 11369 was tolerant for finger millet blast disease.

EVALUATION OF FINGER MILLET GERMPLASM FOR RESISTANCE TO BLAST 161 Table 2. DI of neck blast and finger blast of finger mil let germplasm. Variety/ Neck blast Finger blast Germplasm Maha 2013/14 Maha 2014/15 Maha 2013/14 Maha 2014/15

Oshadha 11.2 a 17.1 a 12.0 a 17.4 a Rawana 31.9 A 38.8 A 43.3 A 52.4 A Line 12415 17.2 Ba 23.5 Ba 20.0 Ba 26.3 Ba Line 12263 26.0 Ab 52.4 Ab 36.0 Bb 50.0 Ab Line 12274 17.4 Ba 28.1 Aa 17.4 Bb 28.8 Ba Line 12448 14.0 Ba 19.8 Ba 20.8 Ba 20.1 Ba Line 10326 26.6 Ab 30.4 Ab 33.9 Bb 32.3 Bb Line 11352 14.1 Ba 20.6 Ba 17.1 Bb 37.7 Ba Line 11369 9.2 Ba 15.3 Ba 11.8 Ba 16.1 Ba Line 7090 17.5 Ba 27.3 Aa 26.0 Bb 34.5 Ba Line 7088 16.0 Ba 24.0 Ba 22.4 Ab 34.3 Ba Note: Within each column, upper case letter indicates comparison with susceptible check Rawana and lower case indicates comparison with tolerant check Oshadha.

REFERENCES

Agstat. 2015. Pocket book of Agricultural Statistics. Volume IX. Socio-Economic and Planning Centre, Department of Agriculture, Peradeniya, Sri Lanka. 16 p. Barman, J. M. 1990. Host plant resistance for rice plant management in the tropics third international conference on plant protection on tropics: Magnaporthe grisea from India thatare pathogenic to finger millet and to rice. Mycological Research 104:161-167. Euphytica 63: 271-279. Karthikeyan, V., S. S. Gnanamanickam, A. C. Amadioha. 2000. Biological control of Setaria blast (Magnaporthe grisea) with bacterial strains controlling rice blast invitro and in vivo with extracts of Azadirachta indica. Crop Protection 19: 287-290. Mgonja, M.A., Lenne, J.M., Manyasa, E. and Sreenivasaprasad, S. (2007). Finger Millet Blast Management in East Africa. Proceedings of the First International Finger Millet Stakeholder Workshop. Patancheru, Andhra Pradesh, India: International Crops Research Institute for the Semi-AriTropics. Nagaraja, A., Jagadish, P. S., Ashok, E. G., & Krishne Gowda, K. T. (2007). Avoidance of finger millet blast by ideal sowing time and assessment of varietal performance under rainfed production situations in Karnataka. Journal of Mycopathological Research, 45(2), 237240. Venkatarayan, S.V. (1947). Diseases of ragi. Mysore Agricultural Journal. 24:50-57.

Annals of Sri Lanka Department of Agriculture 2016. 18:162 - 168 Short Communication

EFFICACY OF ETHYL FORMATE (16.3 % W/W) IN LIQUID CARBON DIOXIDE (83.7 % W/W) AS A FUMIGANT FOR THE CONTROL OF MEALYBUGS IN PINEAPPLE AND PESTS OF STORED RICE AND MAIZE

I.K. WARSHAMANA 1, P.R.A. WIJESINGHE 1, G.T.S. PERERA 1, T.N.P. FERNANDO 1, S.M.A.C.U. SENARATHNE 2, S.S. WELIGAMAGE 3 H.M.R. BANDARA 4, T. SWAMINATHAN 5 AND L. NUGALIYADDE 6

1 National Plant Quarantine Service, Department of Agriculture, Katunayake, Sri Lanka 2 Food Research Unit, Department of Agriculture, Gannoruwa, Peradeniya, Sri Lanka 3 Plant Protection Service, Department of Agriculture, Peradeniya, Sri Lanka 4 CIC Holdings PLC, CIC House, Kew Road, Colombo, Sri Lanka 5 BOC Limited, New South Wales, Australia 6Formerly, Faculty of Agriculture, University of Ruhuna, Kamburupitiya, Sri Lanka

INTRODUCTION

There is an increasing demand to identify internationally accepted safer fumigants for quarantine and non-quarantine treatment of food items, packaged and stored foods and processing equipment, especially to replace Methyl Bromide (Ekanayake and Sumathipala, 2010). Therefore, we initiated an experiment to determine the efficacy of Vapromate® (Ethyl formate 16.7 % w/w + carbon dioxide 83.3 % w/w), which is available in compressed liquid form for the control of Pineapple Mealy Bug (PMB) (Dysmicoccus brevipes) and pests of stored rice and maize.

MATERIALS AND

METHODS Quarantine Fumigation of Pineapples A total of 96 Pineapples (variety ‘Mauritius’), infested to PMB were used for the experiment. The pineapples were placed inside 12 corrugated cartoon boxes (40X 48X24 cm) at the rate of eight fruits per box. Six pineapple boxes were fumigated using Vapromate® (in 1 m 3 fumigation chambers) @ 360 g Vapromate®/m 3 for a period of 4 hours (the recommended dose for PMB), and the remaining boxes were kept untreated. Out of six boxes containing treated pineapples, three were stored in a cool chamber (at 15 oC) and the remaining three were kept under ambient condition in the laboratory (27 - 31 °C, RH 65-75 %) and followed same procedure for the boxes containing untreated pineapples. Pineapples were withdrawn randomly from each box at the rate of two per box before treatment and at 1 and 7 and 14 days after treatment. The surface of the sampled pineapples was cleaned with fine brushes to remove the dead and live adult and juvenile PMB for counting under a magnifying glass (X10). The surface-cleaned pineapples were evaluated for physicochemical and organoleptic properties as per

163 WARSHAMANA et al. standard procedures.

During fumigation period Ethyl Formate (EF) and carbon dioxide (CO 2) concentrations in the centre of the fumigation chambers were measured at 1 hour intervals with the help of a gas monitor (G450 Multi-gas monitor, Linde Group) to determine the stability of the gas concentration inside the chamber, and to detect any leakages of gas from the chamber. The Chi-Square Test (p=0.05) was performed to determine the independence of treatment effect on pest populations. The ANOVA was performed using SAS 9.1.3 portable soft-ware for quantitative data obtained in physicochemical and organoleptic properties.

Quarantine Fumigation of Rice and Maize A 76m 3 container (L 12.06X W 2.34X H 2.68m) at the Food Research Unit (FRU), Gannoruwa was used for the experiment. This was done for commercial grade red rice (4,440 kg) and maize (4,500 kg) which are heavily infested with grain weevils and borers. Using a 45cm seed sampler (Nobel Trier) a total of six samples of rice and four samples of maize seeds (weighing approximately 250 g each) were drawn randomly from the polysack bags to estimate the pest populations, 1 hour and 7 days before and after treatment. Vapromate ® was applied as recommended by the Linde Group, Germany at the rate of 420g Vapromate®/m 3) and the container was kept sealed for 24 hours. Using a gas monitor, EF and CO 2 concentrations at three points inside the container (front, middle and rear) were measured at 6 hours intervals to determine the stability of the gas concentration inside the container and to detect any gas leakage from the container.

RESULTS AND

DISCUSSION Quarantine Fumigation of Pineapples Before introduction of treatment, there was 17 PMB colonies/fruit on average in pineapples. All the treated pineapples that were either kept under 12 °C or ambient temperature did not have live PMB throughout the two-week experimental period. The untreated pineapples kept under 12 °C had a low number of PMB (6 - 8 colonies / fruit) as compared to those kept under ambient conditions (18 - 26 colonies/ fruit). Hardness, pH, skin colour, flesh colour and internal browning of the treated and untreated fruits

167 ETHYL FORMATE IN LIQUID CARBON DIOXIDE AS A FUMIGANT kept under 12°C and ambient conditions did not show any significant difference (p>0.05) within each sampling day, indicating that Vapromate® treatment had no effect on those characters. However, the Brix value of the treated fruits stored at 12 °C was found to be lower than the untreated and treated fruits stored under ambient conditions. It was also observed that EF and CO 2 concentrations have stabilized within the chamber during treatment.

Fumigation of Rice and Maize The rice and maize grains found to be heavily infested with adults and larvae of four common grain pests; namely, maize weevil (Sitophilus zeamais) (Av 47/250g); rice weevil (Sitophilus oryzae) (Av 94/250g); red flour beetle (Tribolium castaneum) (Av 28/250g); confused flour beetle, (Tribolium confusum) (Av 8/250g). It was evident that almost all insects (larvae and adults) were found dead 24 hours after the treatment. The bulk samples, which was observed 7 days after fumigation has resulted no live insects indicating 100% mortality of pests exposed to Vapromate®. The EF and CO 2 concentrations as detected by the EF monitor was marginally lower than the expected range from 6 hours after the treatment in spite of no gas leakage detected outside the container. This could be due to the absorbance of the fumigants by the rice and maize grains that occupied > 50 % of the container volume.

CONCLUSION

Vapromate® treatment schedule recommended for the control of PMB (Dysmicoccus brevipes) in pineapple (4 hours exposure to a dose of 360 g/m 3) gave 100% mortality to the insects within 1 hour after the treatment. Post treatment cold storage of pineapples at 12 °C, further minimizes the population growth of PMB. The above treatment did not show any negative effect on the physiochemical and organoleptic properties of pineapples. Similarly, Vapromate® treatment schedule recommended for the control of general stored grain pests of rice and maize (24 hours exposure for a dose of 420 g/m 3) resulted in 100 % mortality to both larvae and adults of maize weevil (Sitophilus zeamais), rice weevil (Sitophilus oryzae), red flour beetle (Tribolium castaneum), confused flour beetle (Tribolium confusum). Thus, Vapromate® can be recommended for pre-shipment fumigation of pineapple and for pre-entry and nonquarantine treatment of stored rice and maize under commercial scale use in Sri Lanka.

168 WARSHAMANA et al.

ACKNOWLEDGEMENT

Authors wish to extend their sincere gratitude to Dr. J. Senanayake, Head, National Plant Quarantine Service, Katunayake, Dr. H. Sarananda, Head, Fruit Research Unit, Gannoruwa, Mr. A.M.C.T. Abeykoon, Ms. A.N. Abeykoon and Ms. Y.M.C.K. Herath, Plant Protection Service, Gannoruwa and to Mr. S. Madusanka and Ms. T. Wanasundera, at CIC Holdings PLC.

REFERENCES

Damcevski, K.A., G. Dojchinov and V.S. Haritos. 2003. VAPORMATE a formulation of ethyl formate with CO2, for disinfestations of grains. In: (E.J. Wright, M.C. Webb and E. Highleyeds) Proceedings of the Australian Postharvest Technical Conference, Canberra: Ekanayake H.M.R.K and W.L. Sumathipala. 2010. Field guide on pest management strategies as alternatives to methyl bromide. OUSL and UNDP. p 51 Lima C.P.F. 2010. Fumigation of citrus using ethyl formate as a quarantine treatment. Department of Agriculture and food, Western Australia, Perth. p 34. Ryan R. and S. Bishop. 2003. Vapromate: Non-flammable ethyl formate liquid carbon dioxide fumigant mixture. In: (Eds: E.J. Wright, M.C. Webb and E. Highleye) Proceedings of the Australian Postharvest Technical Conference - Stored grain in Australia, Canberra. Saayman T. 2011. Pilot study to determine the efficacy of a fumigation product as a replacement for Methyl Bromide for the control of insect pests on stored grains. Report prepared by Plant Protection Research Institute, Queenwood, Pretoria. Wasala W.M.C.B., C.A.K. Dissanayake, C.R. Gunawardena, R.M.N.A. Wijewardena, D.M.C.C. Gunathilake and B.M.K.S. Thilakarathne. 2016. Efficacy of insecticide incorporated bags against major stored paddy in Sri Lanka. Procedia Food Science 6: 164-169

Annals of Sri Lanka Department of Agriculture 2016. 18: 169 - 168 Short Communication

EFFECTS OF PLANT DENSITY AND CULTIVAR ON GEOMETRICAL PROPERTIES OF BULB AND BULB YIELD OF CLUSTER ONION (ALLIUM CEPA L.)

H.M.C. HITINAYAKE 1, J.P. SUMANARATHNE 2, M.G.N. MADHUSHIKA 1, W.A.D.S. ABEYSEKARA 1 AND K.G. SWARNALATHA 1 1 Regional Agricultural Research & Development Centre, Aralaganwila, Sri Lanka 2 District Secretariat Office, Moneragala, Sri Lanka

INTRODUCTION

Onion (Allium cepa L.) is considered as the second most important vegetable and the most widely used spice in the world. China is the major onion producer in the world which produces about 20,907,759 mt (Nisha, 2016). Sri Lanka produced 1,505,30 mt of onion in 2015 (DCS, 2015). Red onions are a major component in the diet of Sri Lankan households and a high value cash crop of the Dry and Intermediate Zones (Selvarajah and Sivarajah, 2014). Cluster onion (Red onion) production in Sri Lanka is 61,200 mt in 2015 (DCS, 2015). Vethalan, Thinnavely Red, Jaffna Local and Thelulla Selection are the cultivars that are cultivating in Sri Lanka. Rambawa White is not cultivated and it has a tendency for popularized in cultivated area. These cultivars are grown at different spacing in each location. Therefore, finding of best plant density for different cultivars is important for the quality and yield of the cluster onion. Geometrical properties such as size, shape and area are essential for analysis of the behaviour of the onion product during processing or during design of any equipment for processing and storage (Kaveri and Thirupathi, 2015). This study aimed at investigating the effect of plant density and cultivars for geometrical characters of the bulb and yield of the cluster onion.

MATERIALS AND METHODS

The held experiment was conducted at the Regional Agricultural Research and Development Centre, Aralaganwila (DL 2b), Sri Lanka during the 2014 Yala season. Treatments were arranged in randomized complete block design with three replicates. Plot size was 1m x 1m. Factorial combination is consisted with two factors having three row spacing (8 cm x8 cm, 10 cm x 10 cm and 15 cm x 15 cm) with 156, 100 and 44/m 2 plant densities with five cultivars (Jaffna Local, Vethalan, Thinnavely Red, Rambawa White and Thelulla Selection). All the other cultural practices were done according to the Department of Agriculture recommendation. Bulbs were separated 2 weeks after harvesting from the cluster and 10 randomly selected bulbs were used to measure

170 HITINAYAKE et al. geometrical characters viz., polar diameter (mm), equatorial diameter (mm) and shape index. Polar diameter (Dp) and equatorial diameter (De) of bulbs were measured with 0.01 mm least count of digital vernier caliper. Polar diameter is the distance between the onion crown and the point of root attachment to the onion, whereas, equatorial diameter is the maximum width of the onion in a plane perpendicular to the polar diameter (Kaveri and Thirupathi, 2015). Shape index (SI) was defined as the ratio of the equatorial diameter to the polar diameter (Equation 1). A spherically shaped onion having a shape factor of one. Oblate onions have a shape factor > 1 and < 1 for the prolate shape (Essa and Gamea, 2003).

Si = Polar diameter/ Equatorial diameter (Equation 1)

Total bulb yield was measured and the mean values subjected to the Analysis of Variance (ANOVA) using SAS version 9.1 computer software (SAS, 2008) and mean separation was done using Duncan Multiple Range Test at a = 0.05.

RESULTS AND DISCUSSION

Results indicate that there were no significant interaction (P > 0.05) between variety and plant densities (row spacing) on total yield, polar diameter, equatorial diameter and shape index at 0.05 % probability level. Main effect of variety did not significantly affect (P > 0.05) on total bulb yield whereas plant density significantly affected (P < 0.05) on the total yield of the cluster onion (Table 1). The total bulb yield has decreased with the increase of the row spacing from 8 cm to 15 cm. Kahsay et al. (2013) also found the decreasing of onion yield with the increasing of intra row spacing. But Gashua and Abbator (2013) indicated the opposite result to this.

Raw spacing did not significantly (P > 0.05) affect on the polar diameter while variety had an effect (Table 2). Kahsay et al. (2013) also revealed this result whereas found the significant effect of the intra raw spacing to the bulb length. Variety Vethalan showed the highest polar diameter (25.9 mm) and the highest equatorial diameter (23.8 mm). Variety and raw spacing significantly affect for the equatorial diameter and shape index. Row spacing 15 cm x 15 cm gave the highest equatorial diameter (20.6 mm). Thelulla Selection, Jaffna Local and Rambawa White showed the highest shape index. Row spacing 8 cm x 8 cm showed the highest shape index (1.43) and row spacing 15 cm x 15 cm showed lowest shape index (1.15). When raw spacing increases equatorial diameter of bulb tended to increase, decreasing the shape index of the bulb.

Tablet. Effect of variety/cultivar and row spacing for total yield of cluster onion.

PLANT DENSITY & CULTIVAR EFFECT ON BULB PROPERTIES CLUSTER ONION 171 Treatments Total Yi eld (t/ha)

Variety/Cultivar Jaffna Local 8.6 a Vethalan 8.8 a Thinnavely Red 6.6 a Rambawa White 8.1 a Thelulla Selection 6.5 a CV% 37.2

Row spacing 8cm x 8cm 11.0 a 10cm x 10cm 7.0 b 15cm x 15cm 5.5 b CV% 37.2 Note: Means followed by the same letter in each column are not significantly different at p = 0.05.

Table 2. Effect of variety and row spacing for Polar diameter, equatorial diameter and shape index. Treatments Polar diameter (mm) Equatorial diameter (mm) Shape index Variety/cultivar Jaffna Local 22.8 bc 18.0 bc 1.29 ab Vethalan 25.9 a 23.8 a 1.09 b Thinnavely Red 23.7 b 20.1 b 1.18 b Rambawa White 23.1 bc 16.5 cd 1.44 a Thelulla Selection 21.2 c 14.9 d 1.47 a CV % 9.64 13.6 19.1 Row spacing 8cm x 8cm 23.7 a 17.3 b 1.43 a 10cm x 10cm 22.8 a 18.1 b 1.29 ab 15cm x 15cm 23.5 a 20.6 a 1.15 b CV % 9.64 13.6 19.1 Note: Means followed by the same letter in each column are not significantly different at a = 0.05.

CONCLUSION

High bulb yield could be obtained by planting cluster onion at 8 cm x 8 cm spacing (156 plants/m 2) irrespective of the cultivar used in the study. Therefore, 8 cm x 8 cm spacing is suitable for all the cultivars. Plant density did not affect on the polar diameter and plant density and cultivar affect for equatorial diameter. Polar diameter depends on the cultivars. Therefore, designing of grading machine depends on the cultivar and plant density. Big bulbs can be taken by decreasing plant density and Vethalan is suitable for production of large size bulbs. Shape index of all the cultivars with the different densities get > lvalue. Therefore, they all take oblate shape.

172 HITINAYAKE et al. REFERENCES

DCS. 2015. Extend and production of seasonal crops: 2002 - 2015. Department of Census and Statistics, Sri Lanka. Retrieved from www.statistics.gov.lk/agriculture/seasonal crops national totals.html. Essa, A.H.A. and G.R. Gamea. 2003. Physical and mechanical properties of bulb onions. Retrieved from https://www.Researchgate.net/publication/260273942 Gashua, I.B. and A. Abbator. 2013. Effect of plant population density and varietal differences on yield and yield components of onion (Allium cepa L.) in North Eastern Nigeria. International Journal of Agronomy and Agricultural Research 3:22 - 27. Kahsay, Y., D. Belew and F. Abay. 2013. Effect of intra raw spacing on yield and quality of some onion varieties ( Allium cepa L.) at Aksum, Northern Ethiopia. African Journal of Plant Science 7: 614- 618 Kaveri, G. and Thirupathi.V. 2015. Studies on geometrical and physical properties of CO 4 onion bulb (Allium cepa L.var. Aggregatum Don.). International Journal of Recent Scientific Research, 2015. Accessed on 2016.05.17 from http: // www.recentscientific.com Nisha, 2015. Top ten onion producing countries in the world, 2015. Perfect Insider, 2016 retrieved from www.perfectinsider.com > TRADE > Top ten onion producing countries in the world, 2015. SAS, 2008. SAS/STAT, Statistical Software. Version 9.1, SAS Institute Inc., Carry. NC27513.USA Selvarajah, A. and P. Sivarajah. 2014. Factors affecting the quantity of red onions marketed in Trincomalee district Retrieved from www.pdn.ac.lk/ipurse/2014/ proceeding book/EM/44.pdf.

Annals of Sri Lanka Department ofAgriculture 2016. 18: 173 - 176 Short Communication

EFFICACY OF CARBOSULFAN 200G/L SC AND DIAZINON 500G/L EW FOR THE MANAGEMENT OF PADDY BUG (LEPTOCORISA ORATORIUS) IN SRI LANKA

SARATHCHANDRA S.R. 1, PERERA D.T.B. 2, ABEYSEKARA A S K . \ WICKREMASINGHE S. 1, KAHAWATTA U.C. 1, AND NUGALIYADDE L. 3

1 Rice Research and Development Institute, Batalagoda, Sri Lanka 2 Department of Zoology, University of Peradeniya, Sri Lanka 3 Formerly, Faculty of Agriculture, University of Ruhuna, Mapalana, Sri Lanka

INTRODUCTION

Paddy bug (Leptocorisa oratorius, Hemiptera: Alydidae), is a serious pest of rice in tropical Asian countries including Sri Lanka (Berg Van Den and Soehardi, 2000). A series of experiments were conducted (from 2013 to 2015) to evaluate the toxicity levels of Carbosulfan 200g/L SC, Diazinon 500g/L EW (recommended by the Department of Agriculture- DOA) against paddy bug to re-assess their suitability for the management of the pest.

MATERIALS AND METHODS

Experiment 1: Toxicity of Carbosulfan and Diazinon on paddy bug through topical application: Bio-assays on female adult paddy bug were conducted by topical application of the test insecticides (diluted in water: iso-propanol 1:1) @ 0.5 pl to the thorax region of insects. Six dilutions of Carbosulfan (ai 200, 400, 600, 800, 1,000 and 1,200ppm) and Diazinon (ai 250, 500, 750, 1,000 and 1,500ppm) were tested with an untreated control (water: iso-propanol 1:1). After treatment, the insects were held in petri dishes (10cm diameter) lined with moistened filter paper and pieces of rice panicles. Mortality was assessed 24-hr after the treatment and the values were corrected with those of the control using the Abbott’s formula (Abbott, 1987). Using Probit analysis the percentage mortalities were plotted against the concentration of the active 2 ingredient to estimate correlation coefficient (r ) and to obtain LC 50 and LD 50 values.

Experiment 2: Toxicity of Carbosulfan and Diazinon on paddy bug through space treatment : Field collected adult paddy bugs were introduced into wire-meshed wooden cages (60 X 90 X 120cm) @ 15 paddy bugs/cage containing panicle bearing rice plants. Five dilutions of Carbosulfan (ai 400, 600, 800, 1,000 and 1,200ppm) and Diazinon (ai 500, 750, 1,000 and 1,500 and 2,000ppm) were sprayed separately to the caged plants and the mortality of paddy bugs were counted 24-hr thereafter. The experiment was

174 SARATHCHANDRA et al. replicated three times with an untreated control. As in experiment 1, the LC 50 values of the insecticides and correlation coefficient (r 2) were determined.

Experiment 3: Field testing of Carbosulfan and Diazinon: Two insecticides along with an untreated control were tested in a Randomized Complete Block Design (RCBD) with four replicates in a farmer field close to Rice Research & Development Institute (RRDI), Batalagoda. Each plot measured 10 X 10m and the test insecticides were applied separately to plots at the recommended rates (Carbosulfan @ 1,600ml/ha; dilution 40ml/10L and Diazinon 1,200ml/ha; dilution 30ml/10L) at flowering stage. The paddy bug populations in each plot were estimated through sweep net sampling (20 sweeps/ plot) before spraying, 24 and 72 hours after spraying. At maturity, panicles were harvested randomly with 20 panicles/ plot. The grains were then separated into filled and unfilled grains and their weights were recorded at 12% moisture. Grains damaged by paddy bugs were estimated using a staining technique (Sugimoto and Nugaliyadde, 1995) and SAS 9.1.3 portable soft-ware was used for statistical analysis. An un-replicated trial was conducted in Gampola-wela Yaya, Gampola to confirm the efficacy of the above insecticides against paddy bug. The test insecticides were applied separately to 1,200m 2 plots leaving similar area as untreated control. The paddy bug populations in each block were estimated through sweep net sampling with 20 sweeps/sample in three replicates before spraying, 24 and 72h after the spraying. ANOVA procedure was followed to analyze the data using SAS 9.1.3 portable soft-ware.

RESULTS AND DISCUSSION

Experiment 1: Toxicity levels of Carbosulfan and Diazinon on paddy bug through topical application: The dose responses of Carbosulfan and Diazinon on paddy bug in logarithmic curves were found to be with high r 2 values of 0.96 and 0.95, respectively.

Based on the dose mortality equations, the LC 50 values for Carbosulfan ai and Diazinon ai were estimated as 254.5 and 566.7ppm, respectively. Using the mortality equations, the percentage mortalities for Carbosulfan and Diazinon estimated as 85.4 and 89.8%, respectively indicating that the recommended dilutions of the above insecticides provide more than 85% control of paddy bug. The LD 50 values for Carbosulfan and Diazinon on paddy bug was estimated as 10.4 (95% CI 3.12 - 21.34) and 9.7 (95% CI 2.17 - 17.54), respectively.

EFFICACY OF CARBOSULFAN AND DIAZINON ON PADDY BUG 175

Experiment 2: Toxicity of Carbosulfan and Diazinon on paddy bug through space treatment: The dose responses of Carbosulfan and Diazinon on paddy bug in logarithmic curves were found to be with high r 2 values of 0.90 and 0.94, respectively.

Based on the dose mortality equations, the LC 50 values for Carbosulfan ai and Diazinon ai was estimated as 273.4 and 323.75ppm (The dilutions of Carbosulfan ai and Diazinon ai is recommended for paddy bug control as ai 800 and 1,500ppm, respectively). Using the mortality equations, the percentage mortalities for Carbosulfan and Diazinon was estimated as 84.9 and 96.0 ppm, respectively indicating that the recommended doses provide more than 85% control of paddy bug.

Experiment 3: Field testing of Carbosulfan and Diazinon: Paddy bug populations in treated plots (range 2.00 - 4.75 paddy bugs /20 sweep samples) were significantly lower than those in the untreated plots (range 27.25 - 28.75 paddy bugs/20 sweep samples) indicating that the tested insecticides were equally effective against the paddy bug. The weight (g) of the unfilled grains in insecticide treated plots was significantly lower (0.91 - 1.17g / 20 panicles) than those in the untreated plots (2.25g/ 20 panicles) and the percentage grains showing paddy bug damage among the filled and unfilled grains were significantly lower in treated plots (range 0.92 - 1.45) as compared to those from untreated plots (7.85 - 11.56). Paddy bug populations in Carbosulfan and Diazinon treated plots in Gampola Wela Yaya were significantly lower (range 1.0 - 2.3 paddy bugs/ 20 sweep samples) than those in the untreated plot (range 15.1 - 19.3 paddy bugs/ 20 sweep samples) in 24 and 72 hours after treatment. This information can be used as a baseline in future resistance development studies on paddy bug and for re-validation of the efficacy of insecticides tested. There are only a few studies that have been undertaken in Sri Lanka to determine the toxicity level of insecticides on the target pests to determine the correct dosage in order to minimize the resistance development in pests for respective insecticides (Karunaratne et al, 2007; Marasinghe et al, 2016).

CONCLUSION

The recommended doses of Carbosulfan 200 g/L SC and Diazinon 500 g/L EW found to be effective (mortality >85%) in controlling paddy bug.

ACKNOWLEDGEMENTS

Authors wish acknowledge the Innovative Pesticide Marketing (Pvt) Ltd, Colombo, Sri Lanka and Asiatic Agricultural Industries Pvt Ltd, Singapore for the samples of Carbosulfan 200g/L SC and Diazinon 500g/L EW provided for the study.

176 SARATHCHANDRA et al.

REFERENCES

Abbott W.S. 1987. A method of computing the effectiveness of an insecticide. Journal of the American Mosquito Control Association 3(2): 302-303. Berg Van D. and Soehardi, 2000. The influence of rice bug Leptocosa oratorius on rice yield. J Appl Ecology. 37, 959-970 Karunaratne S.H.P.P., K.C. Weerakoon, L. Nugaliyadda and G.K. Manuweera. 2007. Susceptibility of rice insect pests and their natural enemies to commonly used insecticides. Journal of National Science Foundation 35(2): 97-102. Kobayashi T. and L. Nugaliyadde. 1988. Studies on the insect fauna attacking rice panicles in Sri Lanka. JARQ, Japan 21 (4): 314-322. Marasinghe J.P., K.S. Hemachandra, L. Nugaliyadde and S.H.P.P. Karunaratne. 2016. Control failure of Sri Lankan whitefly (Bemisia tabaci) is due to high resistance development against recommended insecticides (accepted for publication in Journal of National Science Foundation) Sugimoto A and L. Nugaliyadde. 1995. Damage of rice grain by the rice bug, Leptocorisa oratorius. JIRCAS Journal 2: 13-17.

Annals of Sri Lanka Department ofAgriculture 2016. 18:177 - 176 Short Communication

THE EFFECT OF FLOWERING PLANTS TO ENHANCE NATURAL ENEMY POPULATION IN PADDY FIELDS

M.A.R.A. MANDANAYAKE 1, M.G.D.L.PRIYANTHA 2, A.P.BENTOTA 1, U.G.A.I. SIRISENA 3, A.M.K.R. BANDARA 3, U.C. KAHAWATHTHA 1 1 Rice Research & Development Institute, Batalagoda, Ibbagamuwa, Sri Lanka 2 Seed certification Service, Gannoruwa, Peradeniya, Sri Lanka 3 Faculty ofAgriculture, Rajarata University of Sri Lanka

INTRODUCTION

Rice fields in Sri Lanka often have a great diversity of naturally occurring arthropod groups that function as predators and parasitoids. Their diversity and abundance are the key indicators of the degree of biological control services present in an ecosystem (Viggiani 2003, Gurr et al., 1998). Maintaining ecological compensation areas such as flowering plant is one of the easiest ways to conserve natural enemies in agricultural landscapes through providing resources such as nectar, pollen, physical refugee, alternative prey and alternative hosts conservation (Greathead, 1979), however such information on the effect of habitat manipulation for rice pest management in Sri Lanka is lacking. Therefore, the present study was conducted to assess the impact of flower-border on insect pest of rice and associated natural enemies.

MATERIALS AND METHODS

This study was conducted in Yala 2015 and Maha 2015/2016 at the Rice Research and Development Institute (RRDI), Batalagoda in Sri Lanka. Two research fields located (1/2 Ac) 700 m apart were selected to cultivate rice (Variety Bg 360) in each using conventional methods including the use of fertilizers and pesticides and without using pesticides. A flower border was established surrounding the field without insecticides with flowering plants of ‘Atapethia’ (Tagets lemmonii) and “Zinnia ’(Zinnia elegans) species. Two rows of each flowering plant were established at 30 cm distances, alternatively, making a 1.5 m border around the field. Sampling was done from each field to collect insect pest and natural enemies using sticky trap and sweep nets, starting four weeks after transplanting and continued at weekly intervals. RESULTS AND DISCUSSION

The abundance of insect pests in the conventional and with flower border plots was rather similar. There were no significant differences in the abundance of Brown plant hopper (BPH), Paddy bugs, Mites and Zigzag leafhopper (ZLH) between the conventional and the field with flower border (Table 1). Although, insecticides were applied to the conventional field, a significant reduction in insect pest population was not observed when compared that with the ecologically engineered plot.

178 MANDANAYAKE et al.

Table 1 Abundance of insect pests in the research fields of with and without the flower border during Yala 2015 and Maha 2015/2016 Pest species Yala Maha P value Inter without** with without with (trt*season) Brown plant hopper 421 508 622 541 0.6617 0.9639 Thrips 104 135 47 278 0.0467* 0.1705 Paddy bugs 2 131 102 111 0.7283 0.9999 Mites 496 213 9 55 0.5094 0.2506 Zigzag leafhopper 57 52 45 44 0.5182 0.9572 White -backed plant hopper 3 26 112 42 0.0305* 0.9998 Green leaf hopper 105 162 207 89 0.0162* 0.0097* *The relationship is significantly different, ** with and without border crop

The abundance of all natural enemies, except Cyrtorhinus sp. and Rove beetles were significantly different between the conventional field and the field with flower border. There was significantly higher (P < 0.05) number of hymenopteran species in the field with flower border than in the control (Table 2). The abundance of spiders was also significantly high (Table 2) in the same field when compared with the conventional field.

Table 2. Abundance of Natural enemies in the research fields of with and without the flower border during Yala 2015 and Maha 15/2016. Natural enemy species Yala Maha Interaction P value (trt*season) without with without with Hymenopteran spp. 10 686 131 585 <0.0001* <0.0001* Spiders 49 612 159 673 <0.0001* 0.0024* Coccinellid beetles 43 80 18 66 0.0021* 0.1916 Cyrtorhinus sp. 71 256 169 113 0.1643 <.0001* Rove beetles 19 4 13 12 0.8845 0.1146 Dipteran spp. 93 178 428 198 0.0010* 0.0007* *The relationship is significantly different, ** with and without border crop

Effect of flower-border in pest control: The population of insect pest was significantly lower than the natural enemy population in the field with flower-border (Figure 1) in both Yala and Maha seasons. It was noted that, when the natural enemy population is increased the population levels of insect pest is reduced in both seasons. In contrast to that, the population levels of natural enemies and pests did not show such rhythmical pattern and haphazardly fluctuated, in the field without flower-border.

Relationship of natural enemies and rice insect pests: The population of BPH varied significantly (p< 0.05) varied with the population level of dipteran species (Table 3), although, the relationship was positive. A negative relationships were noted between BPH population with Cyrtorhinus sp. (E= - 0.016) and Rove beetles (E= -0.019 ), both are well known predators of BPH.

EFFECT OF FLOWERING PLANTS TO ENHANCE NATURAL ENEMIES 179

Figure 1 Variation of insect pest and naturral enemy populations in field with flower-border during Yala 2015 and Maha 2015/2016 (ne-Natural enemies; p-insect pests)

Figure 2 Variation of insect pest and naturral-enemy populations in field without flower- border during Yala 2015 and Maha 2015/2016. Note: ne-Natural enemies; p-insect pests.

Table 3 Relationship of natural enemies and rice insect pests in the research fields of with and without the flower- border during Yala 2015 and Maha 15/2016 BPH Thrips PB Mites ZLH WBPH GLH Hymenopteran sp. 0.0712 0.9253V 0.1790 0.0484*V 0.0039*V 0.5937V 0.0004*V Spiders 0.9765 0.7701 0.2007 0.0004* 0.3900V 0.0235*V 0.0023*V Coccinellid beetles 0.1606 0.1000 0.4055V <0.0001*V 0.0148*V 0.4129 0.0115*V Cyrtorhinus sp. 0.7138V 0.4066V 0.8837V <0.0001* 0.0005* 0.1097V <0.0001* Rove beetles 0.5736V 0.0926 0.0014* 0.003*V 0.0019* 0.0028* 0.0001* Dipteran sp. <0.0001* <0.0001* 0.0041*V <0.0001*V 0.0001*V 0.0002*V 0.2557 V *The relationship is significantly different V The relationship is negative

Present study revealed that, field margins are a valuable space to increase the abundance of predators and parasitoids in paddy cultivation. Timely establishment of “Atapethia” and “Zinnia” surrounding the rice fields significantly increased the

180 MANDANAYAKE et al. predator and parasitoid, than in the control field without a border. The flower border may be replaced with suitable flowering plants based on the availability. However, selection of such border plants should be selective, in order to prevent insect pest harboring on them using as an alternate host.

REFERENCES

Greathead, D.J., 1976. A review of biological control in western and southern Europe. Technical communication, common wealth institute of biological control no 7: 182. Gurr, G.M., van Emden, H.F. and S.D. Wratten, 1998. Habitat manipulation and natural enemy efficiency: implications for the control of pests. In Conservation Biological Control (P.Barbosa,ed.), pp.155-183.Academic Press,San Diego. Viggiani, G. 2003. Functional biodiversity for the vineyard agroecosystem: aspects of the farm and landscape management in Southern Italy. Bulletin Oilb/Srop 26: (4): 197-202.

Annals of Sri Lanka Department of Agriculture 2016. 18: 181 - 185

Short Communication

EVALUATION OF RICE LINES FOR DROUGHT TOLERANCE DURING REPRODUCTIVE AND GRAIN FILLING STAGES

T.K. ILLANGAKOON 1, J.M.N.P. SOMARATHNE 1, S.S. PATHTHINIGE 1, C.H. PIYASIRI 1, R.S.K. KEERTHISENA 1, A.P. BENTOTA 1, U.A.K.S. UDAWELA 1, W.M.W. WEERAKOON 2 AND B. MARAMBE 3

1Rice Research and Development Institute, Batalagoda, Sri Lanka 2 Field Crops Research and Development Institute, Mahailluppallama, Sri Lanka 3 Faculty of Agriculture, University of Peradeniya, Peradeniya, Sri Lanka

INTRODUCTION

Drought is the major abiotic stress causing significant yield reductions in rice in Sri Lanka threatening food security of the country. The Dry zone of Sri Lanka, where nearly 70 % of the paddy is cultivated, has already experienced an increasing number of consecutive dry days in the recent decades (Chithranayana and Punyawardena, 2014). During Yala 2014, 11,723 ha of rice cultivated area were destroyed due to drought (AgStat 2014) while the total rice production was declined by 1.14 million tonnes, about 35.5% of the national production (CBSL, 2014). Therefore, there is an increasing demand for short duration, high yielding and pest and disease tolerant rice varieties for drought prone areas n Dry and Intermediate zones. Rice is extremely sensitive to drought stress than other cereal crops due to its semi-aquatic nature and sensitive periods of rice is categorized as early (from vegetative to mid tillering), intermittent (during mid tillering to panicle initiation) and late (panicle initiation to grain filling) according to their growth stages (Piyasiri et al., 2012). The most critical growth stages of rice are panicle initiation, anthesis and grain filling (Yang et al., 2008) where water stress during these periods can interrupt floret initiation causing spikelet sterility and grain filling resulting in lower grain weight and poor yield (Botwright et al., 2008). The present study was conducted to identify promising drought-tolerant rice lines based on the performance of agronomic traits under simulated drought conditions during reproductive and grain filling stages.

MATERIALS AND METHODS

The experiment was conducted in Yala 2015 at the Rice Research and

Development Institute (RRDI), Batalagoda (IL 1a agro-ecological region), Sri Lanka. The soil type of the experimental site was a mixture of low humic glay and red yellow podsolic soils. Twenty advance rice lines (F8-F9) belong to three months age group together with the nine entries including five exotic lines (IRDTN 22, IRDTN 56, IRDTN 37, IRDTN 11 and CNI 9028), three varieties recommended by the Department

182 ILLANGAKOON et al. of Agriculture, Sri Lanka (Bg 250, Bg 300 and Bg 304 and Bg 251 (recommended drought tolerant variety) were screened. Pre-germinated seeds were planted as rows (single row/entry) at spacing of 20 x 15 cm in a Randomized Complete Block Design (RCBD) with three replicates at timely intervals to synchronize the reproductive periods of all entries based on their maturity dates. Basal fertilizer and top dressings were applied as per the recommendations (DOA, 2013). Irrigation was made during the vegetative period and drought stress was imposed at the beginning of panicle initiation and was continued up to the end of maturity period.

Gravimetric soil moisture status in each replicate was measured at weekly intervals after drought stress was induced. The soil moisture content of the irrigated condition was maintained above 35 % (w/w) for the whole growing period. Number of days to 50% heading , days to physiological maturity, panicle length, 10 panicle weight, filled grain % and yield of randomly selected 10 plants/row were recorded separately in drought stress and irrigated conditions. Complete Linkage Cluster Analysis using Ward method in MINITAB was performed to identify the variation pattern among the entries based on agronomic traits. Group data were subjected to analysis of variance (ANOVA) and followed by mean separation with Duncan's Multiple Range Test (DMRT) using SAS statistical software.

RESULTS AND DISCUSSION

The soil moisture content of the experimental site declined approximately from 30 % to 7 % (w/w) within the 12-weeks of drought stress. The 50 % heading of all entries ranged in between 4 th to 6 th weeks after the imposed drought stress where they experienced a moisture reduction at a range of 15.8-10.8 % during the period. Dendrogram produced by using the values of agronomic traits of 29 entries under drought stress condition revealed that four distinct clusters at a Euclidean distance of 4.37 (Figure 1) and the entries belonged to each cluster are listed in Table 1. Accordingly, all IRDTN lines were grouped in Cluster 1. Five advance lines together with CNI 9024, Bg 250 and Bg 251 formed Cluster 2. Cluster 3 comprised with eight advance lines while nine entries including Bg 300 and Bg 304 resulted in Cluster 4. Entries in Cluster 2 flowered and matured early and had the highest panicle weight (13.0 g/10 panicles) with the minimum reduction of weight (38.1 %) under drought condition compared to irrigated condition (Table 2). The filled grain % was high in entries of Cluster 1 and 2. However, the highest yield and minimum reduction compared to irrigated condition was recorded by the entries of Cluster 1 (53.1 g/10 plants and 22.8 %, respectively). Previous studies have shown that IRDTN lines have a high density of leaf trichomes and a well-distributed deep, thick root system enabling them to reduce water loss and to use water stored in deep soil layers during drought stress (Illangakoon and Somaratne, 2014). Entries of the Cluster 2 recorded the next highest yield (36.9 g/10 plants). The entries grouped into Cluster 3 and 4 had both lower

EVALUATION OF RICE LINES FOR DROUGHT TOLERANCE 183 filled grain % and yields with higher reduction of those traits under drought compared to irrigated condition.

Among the entries belonged to Cluster 1, IRDTN 11 had a significantly higher yield under drought condition (70 g/ 10 plants) while yields of the other three lines were ranged in between 45-50 g/10 plants but, not statistically varied among each other (Figure 2 A). Wasala et al. (2015) reported that IRDTN 11 performed better under induced drought stress condition during reproductive stage. None of the entries in Cluster 2 produced higher yields comparable to IRDTN 11, but Bg 14-2448 and Bg 14-2450 recorded higher yields compared to Bg 251 (Figure 2 B). Advance lines including Bg 142349, Bg 14- 2449 and Bg 14-2437 produced comparable yield to Bg 251.

Figure 1. Dendrogram produced by Complete Linkage and Euclidean distance for the 29 entries based on agronomic traits under simulated drought stress

184 ILLANGAKOON et al. Table 1. Cluster membership of rice entries.

Cluster 1 Cluster 2 Cluster 3 Cluster 4 IRDTN 56 CNI 9024 Bg 14 -2341 Bg 14 -2342 IRDTN 37 Bg 250 Bg 14 -2439 Bg 300 IRDTN 22 Bg 14 -2437 Bg 14 -2440 Bg 14 -2365 IRDTN 11 Bg 14 -2448 Bg 14 -2364 Bg 14 -2436 Bg 14 -2450 Bg 14 -2435 Bg 304 Bg 14 -2449 Bg 14 -2366 Bg 14 -2343 Bg 14 -2349 Bg 14 -2434 Bg 14 -2348 Bg 251 Bg 14 -2907 Bg 14-2345 Bg 14-2346

Table 2. Means of agronomic traits of four clusters under drought stress and % delay/reduction of the trait compared with irrigated condition.

Agronomic trait Cluster 1 Cluster 2 Cluster 3 Cluster 4 DS D/R DS D/R DS D/R DS D/ R Days to 50 % 79.0 ±5.4 9.3 66.0.±3.5 3.1 78.0±4.5 3.0 77.0±3.1 9.4 heading 12. Days to maturity 112.0±3.9 101.0±3.7 6.2 111.0±4.4 5.9 111.0±2.0 9.5 6 Panicle length 19. 24.3±1.1 1.4 21.3±1.8 4.5 18.5±1.8 23.1±2.7 2.9 (cm) 6 Weight of 10 11.9±5.0 61. 13.0±4.0 38. 6.5±2.7 67. 7.3±2.5 64. panicle (g) 3 1 2 0 Filled grain % 80.0±7.4 15. 81.9±2.0 15. 45.1±24.9 52. 48.9±22.9 48. 2 6 6 8 Yield /10 plants 22. 39. 86. 72. 53.1±11.0 36.9±14.2 9.0±7.2 16.5±20.1 (g) 8 2 9 2

Figure 2. Yield of 10 plants of the entries of Cluster 1 and 2; A. Cluster 1, B. Cluster 2. Vertical bars indicate ± standard error. Mean s followed by the same letters are not significantly different by the DMRT at p > 0.05

Note: Values with ± indicates standard deviation, DS = Drought stress, D/R = % Delay or reduction compared with irrigated condition

EVALUATION OF RICE LINES FOR DROUGHT TOLERANCE 185 CONCLUSIONS

The line IRDTN is the most promising entry while IRDTN 56, IRDTN 37 and IRDTN 22 also perform well under drought imposed conditions during the reproductive and grain filling stages. Among the 20 advance lines tested, Bg 14-2448 and Bg 14-2450 are the most promising lines followed by Bg 14-2349, Bg 14- 2449 and Bg 2437. Studying the physiological mechanisms behind the drought tolerance of these entries will be an added advantage for better use of them in future breeding programs.

ACKNOWLEDGEMENT

Authors wish to acknowledge the financial assistance given by the National Research Council of Sri Lanka (Grant No: NRC-14-24) for the project “Ensuring food security through developing climate smart crop varieties and cultivation techniques in Sri Lanka” to conduct this study.

REFERENCES

AgStat, 2014. Department of Agriculture, Sri Lanka XI:8. Botwright A., H.R. Latte and L.J. Wade. 2008. Genotype and environment interactions for grain yield of upland rice backcross lines in diverse hydrological environments. Field Crops Research 108(2): 117-125. CBSL, 2014. Annual Report, Central Bank of Sri Lanka 6:101. Chithranayana, R.D. and B.V.R. Punyawardena. 2014. Adaptation to the vulnerability of paddy cultivation to climate change based on seasonal rainfall characteristics. Journal of National Science Foundation of Sri Lanka. 42(2): 119-127. DOA. 2013. Fertilizer recommendation for rice. Department of Agriculture, Peradeniya. Sri Lanka. Illangakoon, T.K. and J.M.N.P.Somarathne. 2014. Variation in morpho-physio traits of selected rice (Oryza sataiva L.) germplasm in response to water stress during the vegetative phase. Annals of Sri Lanka Department of Agriculture 16:45-57. Piyasiri C.H., W.M.W. Weerakoon, D.M.N. Dissanayake, L.C. Silva, T.N.N. Priyadarshini, W.M.U.S. Geethika, M.Y.A.S. Rathnayake and H.A.N.S. Hettiarachchi. 2012. Rice varieties for moisture stressed ecosystems. Annals of Sri Lanka Department of Agriculture 14:97-113. Wasala.S.K., N.M. Ubeysekara, P.S. Gunasekara, N.K. Wikcramasooriya, S.O. Senaviratne, S.P .Karunarathne, C.M. Senavirathne, L.C. Silva, D.M.J.B. Senanayake, T.K. Illangakoon, N.P. Somarantne and N.R. Abeynayake. 2015. Screening of rice germplasm for response to drought at reproductive stage under drought stress condition. Annals of Sri Lanka Department of Agriculture. 2015. 17:47-50 Yang, J.C., K. Liu, S.F. Zhang, X.M. Wang, Zh Q. Wand and L.J. Liu. 2008. Hormones in rice spikelet in response to water stress during meiosis. Acta Agronomisa Sinica, 34 (1): 111118.

Annals of Sri Lanka Department of Agriculture 2016. 18: 186 - 185 Short Communication

APPLICATION OF HOT AIR AS A DE-VITALIZATION TREATMENT FOR WEED CONTAMINANT IN COIR AND COIR BASED PRODUCTS

L. D. K. ARACHCHIGE, D.P.P. JAYAKODY AND D I M . AMARARATHNA

National Plant Quarantine Service, Canada Friendship Road, Katunayake, Sri Lanka

INTRODUCTION Coco peat, a by-product of coconut fibre industry, is well reputed as an ecofriendly natural, renewable growing medium for its physiochemical properties preferable for plant growth (Coco Substrates, 2011). During 2012, Rs. 6,118 million have been earned by exporting coco peat products by 46 companies (Central Bank, 2012). Contamination of coir with weed seeds in export product causes rejections both locally and after exportation (James at el., 2012). The National Plant Quarantine Service of Sri Lanka facilitates grow-out test to detect viable seeds of coir products, which demands nearly a month and it is not an efficient method. Heat treatment of coco peat is a good alternative to destroy weed seeds (New Zealand MOA&F, 2008), which is being practiced by a few local exporters. Hence, the present study was undertaken to optimize hot air treatment that devitalizes the weed seeds in coir while keeping expansion power and moisture content at acceptable ranges.

MATERIALS AND METHODS

Seventeen weed species (Table 1) were selected based on the availability and recorded in noncompliance. The experiment was conducted at the National plant Quarantine Services, Katunayake by using a locally fabricated hot air generator (Figure 1a). The experiment consisted of two trails.

Trial 1-Direct exposure of weed seeds to the hot air: Weed seed sacks and seeds were subjected to 0 0 100 C -110 C temperature for given time periods (Ti - 30 min, T 2- 45 min, T 3- 60 min, T 4- 120 min,

T5- 180 min, T 6- 240 min ) by repeating three times (Figure 1b). Treated seeds of species 1 to 14 were subjected to Tetrazolium test (TTZ) while Crotolaria pallida, Borreria laevis and Eupatorium odoratum were tested for viability with germination test as the embryos were minute in them. Trail 2. Hot air treatment for the weed seeds immersed in to coir: Weed seeds immersed in coir o o were treated with two treatment combinations, (T 5- 180 min at 100 C - 110 C) and (T 6- 240 min at 100 oC -110 oC) (Figure 1c). Moisture content (MC) and expansion power were measured before and after treatments. The experiment was arranged in a Complete Randomized Design (CRD).Mean separation was done according to Duncan s multiple range test (DMRT) by using SAS computer package (SAS, 1992).

APPLICATION OF HOT AIR AS A DE-VIT ALIZATION TREATMENT FOR WEED 187

(a) (b) (c) Figure 1. (a) A locally made hot air generator, (b) heat treatment for weed seeds without coir (c) heat treatment for weed immerse in coir

RESULTS AND DISCUSSION

Impact of time duration vs same temperature condition is explained by results (Table 1). Almost all weeds belonged to the family Fabaceae were highly resistant to higher temperatures as they thrive in the Dry zone, facing long dry spells and subsequent fires (Moody et al ., 1984). Panicum maximum and Melochia cochorifolia were killed after 45 minutes as they were slender seeds. Centrocema pubasence and Cassia occidentalis of family Fabaceae and Urena lobata of Malvaceae family remained viable even after two hours of exposure to 100-110 0 C due to their morphology (Moody et al ., 1984). High temperature decreased water content gradually and led to a distorted structure within the seeds and finally vigour and viability have lost.

The germination percentage of Crotolaria pallida was significantly increased by T 1, T 2, T 3 treatments when compared to that of the control (Figure. 2) while the germination percentage behaved in an opposite manner. However, all three varieties lost viability under the treatment 5. According to the results of trial two (Table 2 and Figure 3), it is understood that weed seeds can remain viable up to four hours when they are immersed in coir. Reasons could be indirect contact of weed seeds with the treatments. Larry et al. (1995) explained that higher soil temperature and nitrate content of surface soil facilitates the breaking down of seed dormancy. Table 1. Tetrazolium test results of weed seed after each treatment

Trial 01 Trail 02 R 100 0C - 110 0C 100 0C - 110 0C

188 ARACHCHIGE et al. Weed Species Family T T1 T2 T3 T4 T5 T6 T5 T6

30 45 60 120 180 240 180 240 min min min min min min min Mi n Tephrosia purpurea Fabaceae + + + ------Pueraria phaseoloids Fabaceae + + + + - - - + - Centrocema pubesens Fabaceae + + + + + - - - - Cassia occidentalis Fabaceae + + + + + - - + - Tephrosia villosa Fabaceae + + + ------Mimosa invisa Fabaceae + + + + - - - + - Hyptis suaveolens Lamiaceae + + + - - - - + - Urena lobata Malvaceae + + + + + - - - - Panicum maximum Poaceae + + - - - - - + - Oryza sativa Poaceae + + + + - - - + - Sesamum radiatum Pedaliaceae + + + + - - - + - Capsicum annum Solanaceae + + + ------Melochia orchorifolia Sterculaceae + + ------

+=viable seeds indicates pink colour; -=No colour formation (dead seeds); R=Replicate; T=treatments.

Table 2. Expansion Power of the coir. Treatments Expansion Power Moisture % 0 T5 100 - 110 C for 180 minutes 4.013 13.45 0 T6 100 - 110 C for 240 minutes 5.667 13.25 Control 6.463 39.49 CV % 6.150 LSD 0.7502

Even though, the statistically analyzed data of expansion power (Table 2) was significant, it is within the acceptable range that demanded by the sector (Balachandran, 1991). Further, moisture percentage of coir should be maintained at 13 -18 % to produce coir blocks and the requirement is fulfilled (Table 2). This simple machine can be made at a low cost for any size. Further, it is the best alternative to dry coir during the wet

APPLICATION OF HOT AIR AS A DE-VIT ALIZATION TREATMENT FOR WEED 189 season by keeping properties at acceptable range. Further studies are required to check the feasibility of the machine in controlling fungal pathogens in coir.

T1 T2 T3 T4 T5 Control T i .100-110 “C 30 minute Tr .100-110T6 °C 120 minute Control c T; .100-110 C 45 minute Ts. 100-110 °C ISO minute c T3.100-110 C 60 minute Treatements irTTTTTimm Crotolaria Crotolaria pallid pallidrmt Borreria rmi laevis BorreriaF7771 Eupatorium laevis odoratum Eupator ium odoratum Figure 2. Germination percentage of Crotolaria pallida, Borreria laevis and Eupatorium odoratum at trail one. Figure 3. Germination percentage of Crotolaria pallida, Borreria laevis and Eupatorium odoratum at trail two

CONCLUSION

Hot air treatment could be successfully applied to devitalize the selected weed species completely at 100 - 110 0C for four hours while keeping MC and expansion power at an acceptable range.

190 ARACHCHIGE et al. REFERENCES

Central Bank, 2012. Annual Report 2012. Colombo, Sri Lanka: Central Bank of SL. Coconut Development Authority, 2013. Coco Fibre Pith for Horticulture. [Online] (date of update 27. 06. 2013) Available at: Department of Agriculture, Fisheries and Forestry, 2012. [Online] Available at: < http://www.daff.qld.gov.au/4790_7028.htm > [Accessed 23 April 2013]. James, T.K., Champion, P.D., Bullians, M. and Rahman, A., 2012. Weed Biosecurity Joshi, A.K. and Singh, B. D., 2005. Seed Science and Technology. Kalyani publishers: Delhi. Moody, K., Lubigan, R.T., Munroe, C.E., Paller, Jr., 1984. Major Weeds of the Philippines. Philippines: Weed science society of the Philippines.

Annals of Sri Lanka Department of Agriculture 2016. 18: 191 - 198

Short Communication

DETERMINATION OF EFFECTIVE YIELD INCREMENT OF SALAD CUCUMBER (CUCUMIS SATIVUS) WITH SUPPLEMENTARY LIGHTING

H.R.U.T. ERABADUPITIYA, R.S. WIJESEKARA AND D.M.N.H.

JAYASEKARA

Extension and Training Centre, Department of Agriculture, Peradeniya, Sri Lanka.

INTRODUCTION Protected culture was initially introduced to protect crops from adverse environmental conditions but later it was advanced to provide optimum conditions for the growing crops to maximize the quality and quantity of the yield. Salad cucumber remains as the highest candidate crop among greenhouse vegetables and at the local market as well as in the case of other leading cucumber producing countries in the world. According to previous studies, it has been showed that the level of light has been a key factor that limits yield of Gherkin cultivation (Karunarathne et al, 2015). Generally, cucurbits plants especially cucumber favors considerable amount of sunlight when compared with other crops (Blando, 2013). Under overcast weather conditions, the light is a limiting factor for photosynthesis. The greenhouse growers encountered reasonable lower production due to recent bad weather conditions prevailed during both Yala and Maha seasons with erratic pattern of rainfall caused by the changing climate. Thus, this study was focused on determination of effective yield increment of salad cucumber with supplementary lighting.

METHODOLOGY

This study was carried out during year of 2015 as two experiments (I and II) under semi intensive greenhouse conditions at Gampola in Kandy district (WM 2a agro ecological zone). Salad cucumber hybrid variety was used as the test crop and, the experiment was laid out as a Randomized Complete Block Design (RCBD). There were two supplementary lighting treatments (T1 & T2), keeping a natural light as the control

(T3) with three replicates. Thirty (30) plants were assigned per each replicate. In T 1, supplementary lighting was provided to extend the day length during 5.00-7.00 and 17.00-19.00 hours with other time when the sky is cloudy resulting low solar irradiance. In T 2, supplementary lighting was limited to overcast (cloudy) weather conditions at the rate of 12W per m 2 plots using LED Grow lights (300w) at the canopy height. Crop

192 ERABADUPITIYA et al. management practices were done according to the standard practices for the salad cucumber (Wijesekara, 2013). Treatments were evaluated by counting the number of days taken for first flowering and marketable yield data per plant. The data were analyzed with one way ANOVA procedure by using, Minitab 17. In Experiment II, the same treatments were tested in the following season (September to December, 2015). In addition other weather parameters such as rainfall, temperature, humidity and outside light conditions were also measured.

RESULTS AND DISCUSSION

Weekly average rain fall data collected at Gannoruwa in 2015 is shown below in Figure 1. It shows that at harvesting stage of both experiments, low solar radiation (higher number of overcast hours) conditions were prevailed. Average light intensity during the experimental periods was approximately

Figure 1. Weekly average rainfall data collected at Gannoruwa (Source:■ Exp 1 NRMC, DOA). ■ Exp 2

Treatment

Figure 2. Effect on supplementary lighting on average number of days taken for first flowering in both experiments. (Different letters indicate statistically different treatment means at P < 0.05).

3035% lower than the open conditions. The light intensity in a sunny day was more than 50,000 lux while under overcast condition, it was about 15,000.

EFFECT OF ARTIFICIAL LIGHT ON YIELD INCREMENT OF SALAD CUCUMBER 193

In both experiments, the treatment effect on number of days taken for first flowering were statistically significant (at P < 0.05) where T 1 was significantly earlier in flowering than T 2 and control (T 3). As plants grow and increase the number of leaves, the need for light increases (Brown, 2015). Average marketable yield per plant was statistically higher in T1 compared to T2

■ Exp 1 ■ Exp 2 a T1 T2 Control and T3.

08 3 b ^ b 0.6 b T b b “ 0 Treatment

Figure 3. Effect on supplementary lighting on cumulative average marketable yield per plant (Different letters indicate statistically different treatment means at P < 0.05).

Influence of supplementary lighting in both experiments for semi-intensive greenhouse cucumber cultivation may cause formation of more fruits with good quality. If light intensity increases, the rate of photosynthesis will increase as long as other

Figure 4. Variation of weekly average marketable yield per plant under different light treatments in Experiment I. (Different letters indicate statistically different treatment means at P < 0.05).

factors are adequately supplied with proper fertigation and agronomic practices.

194 ERABADUPITIYA et al.

When considering both experiments, number of flowers was higher in T1. Therefore, marketable yield at 7 th week (first yield) was significantly higher in T1 than other treatments. In experiment II, more supplementary lighting hours were required than the experiment I due to stormy weather conditions prevailed during the season which resulted longer duration of overcast conditions. When there is long overcast periods hours treatment II is also cost effective compared to the control.

When generating new technologies, more emphasis should be given to sustainability issue. Therefore, introduction of cost effective, economically viable and environmentally friendly supplementary lighting methods are required. It is very important to compare the treatment cost. LED lighting cost estimation was done per plant basis and compared with other available sources (Incandescent and CFL). The LED lighting showed the lowest running cost and in addition to its long life span, higher light emitting efficiency and environmental friendly characters. Thus, LED bulb can be selected as economically viable and cost effective light source.

CONCLUSION

It can be concluded that when overcast weather conditions prevail, supplementary lighting with LED Grow lights together with extended day time lighting can significantly increase the marketable salad cucumber yield while reducing the number of days taken for first flowering under semi-intensive greenhouse conditions in WM 2a region in Sri Lanka.

REFERENCES

Anonymous. 2010. Light and lighting control in greenhouses, Argus control systems ltd., Canada. Wijesekara R.S. 2013. "Arakshitha Gruhathula Bogawagawa", Department of Agriculture, Sri Lanka. Karunarathne, C.L.S.M., Chamindika, B.G.L., Weerakkody, W.A.P., Weerasinghe, K.W.L.K., Hettiarachchi, H.A.N.S. 2015. Influence of supplemental lighting on reducing pre-mature fruit drop and increasing fruit yieldof greenhouse gherkins[on line]. [Accessed on 01.05.2016].Available at http://wwwhttp://tiikm.com/publication/ICOAF-2015-online- proceeding.pdf.

Annals of Sri Lanka Department of Agriculture 2016. 18: 195 - 198

Short Communication

COMPARISION OF TWO TYPES OF MUSHROOM-GROWING HOUSES FOR MUSHROOM PRODUCTION, ENVIRONMENT CONDITIONS AND INSECT ABUNDANCE

P. RAJAPAKSE, N.P.W. JAYARATHNA, N.V.A. MANJULA AND D D E . PIYATHISSA

Regional Agricultural Research and Development Centre, Makandura, Sri Lanka

INTRODUCTION

Mushroom production in Sri Lanka is not sufficient to meet the current and increasing demand within the country. One of the major reasons for the lack of quality mushroom is the insect damage, which directly affects the quality and quantity of the yield. Sciarid flies, phorid flies, cecid flies, mites, springtails, nematodes are some of the mushroom pests (Anon, 2010). As chemical control is not appropriate, farmers use some non-chemical methods such as light trapping, burning of neem leaves to control insect problems, but with limited success. Department of Agriculture of Sri Lanka has recommended to use insect-proof nets for the mushroom-growing houses to prevent entry of insects, which is considered as the most appropriate method to manage this problem. However, the currently used mushroom-growing houses in Sri Lanka consists of a roof, walls, doors and windows that cannot be easily converted to insect proof houses with nets.

Maintaining temperature, ventilation (CO 2 concentration), light and relative humidity (RH) inside the growing housed is necessary to obtain a higher mushroom yield. However, the temperature inside the growing house should suite the variety of mushrooms, where yhe tropical oyster mushroom needs an environmental temperature between 26-30 °C. Temperate varieties such as button mushroom, king oyster and shitake, etc., require cooler conditions with temperatures around 16-18 oC. Misting would be a necessity if the temperature in the mushroom house is too high for the chosen strain. Moreover, requirement of light (colour and intensity) depends on the mushroom strains where oyster mushrooms. Emergence of mushrooms with small caps and longer stems indicate that aeration and light requirements have not been met. In the complete absence of light, oyster mushrooms will emerge without caps but the stipe (mushroom stalk) forming a coral-like structure. Good control of the humidity during cropping is important for all types of mushroom. To maintain high humidity (80 - 90%) water should be sprayed several times per day ( www.researchgate.net/profile ) in the growing house.

196 RAJAPAKSE et al.

The ambient CO 2 concentration in the growing room should be controlled by ventilation, especially during the fruiting body formation and development of mushrooms. Under high CO 2 levels or with less frequent ventilation, mushrooms produce long stipes with tiny caps, while they produce short stipes with broad caps under law CO 2 concentration or frequent ventilation. In mushroom species Pleurotus ostreatus, a CO 2 concentration higher than 1000 ppm will produce stipes that are too long resulting in mushrooms of lower quality (Mushworld, 2004).

Tyvek ® is a newly introduced cladding material that resembles thin plastic paper used for various purposes in agriculture sector in the world. This cladding material has no macro holes, thus provide no opportunities for the insect to go through the material. However, it consists of micro holes supporting exchange of air, thus resulting in same environmental conditions between indoor (inside the growing house with new cladding material) and outdoor ( www.materialconcepts.com/products/tyvek ). The cladding material is guaranteed for five years by the manufactures. According to the producers this material is currently not in use for the mushroom-growing houses in the world. However, the special characters of this cladding material indicate the potential for its use to cover the mushroom-growing houses with the objective of controlling major insect pests of mushrooms. Therefore, this study was carried out with the objective of evaluating the insect pest control efficacy of a new cladding material in mushroom-growing houses.

MATERIALS AND METHODS

A currently used mushroom-growing house (EGH) (Figure 1) and a mushroomgrowing house equipped with the new insect-proof cladding material (TYVEK ®) (NGH) (Figure 2) were compared for productivity and benefit:cost ratio at the Regional Agricultural Research and Development Center, Department of Agriculture (DOA) at Makandura, Sri Lanka during 2014 Maha and 2015 Yala seasons.

Two species of mushroom (Pleurotus ostreatus and P. saju caju) were used and 100 bags of each species were divided in to 20 batches (five bags per batch). The bags were placed in an incubation room to facilitate the growth of mycelium under proper condition after inoculation of spawn. When the fully grown mycelium was visible (28 days after inoculation), 20 batches of each species were placed separately in each growing house. All cultural practices were same as existing oyster mushroom cultivation.

COMPARISION OF TWO TYPES OF MUSHROOM-GROWING HOUSES 197 Figure 1. Growing house-existing type Figure 2. Growing house with new cladding

material

Environmental conditions (temperature, light and relative humidity), insect population (Quadrat Sampling Method), yield (quantity and quality) were recorded and data were analyzed by pooled t-test (p=0.05) using the SAS computer software package. The benefit:cost analysis for mushroom cultivation was performed for both growing houses.

RESULTS AND DISCUSSION

There were no significant differences in the environmental conditions (temperature, relative humidity and light) between the two growing houses. No insects were observed in the NGH equipped with the new cladding material, however, two types of insects were found in EGH.

The total yield of mushrooms did not depend on the growing house, however, there was a significant difference (p<0.05) of the marketable yield between two growing houses. The insect pest damage in the EGH was the main reason for high amount of nonmarketable mushroom under existing type of mushroom-growing house. Proper ventilation inside the growing house is required for a better mushroom yield.

Poor ventilation or higher CO 2 concentration condition could result in horn-shaped (coral shape) mushrooms. However, in the present experiment, horn-shaped or coral-shaped mushrooms were not observed in both growing houses due to proper ventilation. The results also indicate that the new cladding material used also facilitate air movement as provided in the manufacturer’s information. A high benefit:cost ratio (2.36) was reported in the mushroom growing house equipped with new cladding material compared to that of the existing type growing house (2.24).

198 RAJAPAKSE et al.

CONCLUSION

The mushroom-growing house equipped with the new cladding material Tyvek® resulted in similar environmental conditions and proper ventilation, no insect incidence, higher marketable yield and a higher benefit:cost ratio compared to that of the existing- growing houses. Hence, the new growing house type with the insect-proof cladding material is a viable solution to solve insect problems in mushroom cultivation to obtain an economical yield under Sri Lankan conditions.

ACKNOWLEDGEMENT

Authors wish to acknowledge the Deputy Director (Research) of the Regional Agricultural Research and Development Centre at Makandura, Sri Lanka for the valuable guidance given. The financial support given by the KOPIA (Korean Project for International Agriculture) is gratefully acknowledged. The authors also wish to thank the Regius Holding (Pvt) Ltd for providing the Tyvek® cladding material free of charge.

REFERENCES

Anon. 2010. Pests and diseases of mushrooms Available at “ www.daff.qld.gov.au/plants/fruits- vegetable/specialty-crops/pesta-and-Diseases-of-mushroom” Mushworld. 2004. Mushroom Growers Hand Book 1, Oyster Mushroom Cultivation pp 62-63 www.materialconcepts.com/products/tyvek . Properties of Tyvek material (Accessed on 23 rd May, 2015).

Annals of Sri Lanka Department of Agriculture 2016. 18:199 - 185 Short Communication

A SIMPLIFIED NUTRIENT FILM TECHNOLOGY (SNFT) FOR SEED

POTATO PRODUCTION

J.M.D.D. JAYAMANNA, S.M.U.I. SAMARAWEERA AND CD. JAYASINGHE

Regional Agricultural Research and Development Centre, Bandarawela, Sri Lanka

INTRODUCTION At present, approximately 6000 ha of lands in Sri Lanka are under potato cultivation. However, the annual potato productivity during last decade remained at 15 t/ha (Agstat, 2015). Non-availability of good quality, disease free seed potato of desirable varieties at the correct time is considered as the main constrain for increasing the productivity of potato in Sri Lanka. Increasing demand for high quality seed potato at affordable price can only be met by accelerating the multiplication of early generation seed tubers using novel techniques and supplying them for strengthening the formal and informal seed systems (Kularathna et al., 2008). Though various hydroponic and geoponic techniques are used to produce mini tubers (5 - 25 mm diameter with 0.1 - 10 g or higher weight) and pre basic seeds, hydroponics are the most suitable method to produce seed tubers (Mazeen et al., 2008). Higher initial capital and expertise for construction is a big limitation in hydroponics. Therefore, this study was conducted with the objective of introducing simple and cost effective hydroponic seed production technique, a ‘simplified nutrient film technique (SNFT)’ was to compare the efficiency of SNFT with popular deep flow technique (DFT) and substrate culture technique (SCT).

MATERIALS AND METHODS

Initial experiment was carried out in a poly tunnel at Regional Agriculture Research and

Development Centre (RARDC), Bandarawela (IU 3c ) in 2014 Yala. It was laid out as a Completely Randomized Design with 20 replicates in 5 experimental units. The system was re-tested in farmer fields (poly tunnels) at Hela-Halpe (IU 3c), Kappetipola and Labukale in 2015 Yala. Selected farmers have experienced in seed potato production using hydroponics and geoponics in Badulla and Nuwara Eliya districts. Newly introduced SNFT (I) was compared with DFT (II), the most common hydroponic systems for mini-tuber production of potato, and SCT (III) at the first stage

20 0 RAJAPAKSE et al. of the experiment (Plate 1). Same sized GO seed tubers of potato variety Granola were used as planting materials in all locations. Albert’s solution (1.5-2.5 EC) was used as the nutrient source.

Preparation of SNFT system: This system was consisted of normal sunken beds and one bed was 10 ft x 3 ft in dimensions. After lining out the bed, margins were prepared by using roof tiles. Bottom of the bed was levelled thoroughly and removed the gravel and large particles. Then the bed was lined with black polythene and filled with Albert solution (1.5 g of Albert’s mixture dissolved in one litre of water). A metal net (mesh size 2'' x 2'') was placed on the bin and covered with two layers of black and white polythene, one over the other. Inner black polythene provide dark root environment while, white polythene reflects the light and heat at outside. Small incisions (0.5'' x 0.5'') were made in the polythene layer in 2”x 2” distance. Plantlets obtained from GO planted in sand trays were inserted into the incisions (Plate 1). Yield and economic analysis

i=>

( (b) o n

(f) (e) Platel. Preparation steps of SNFT system. Note: (a) Lining out the beds inside the tunnel; (b) bed preparation with roof tiles and leveling of bottom; (c) Polythene layering of bottom and placing the mesh on the bed; (d) Top layering by polythene; (e) one month old cultivation; (f) harvesting by opening the bed DFT system was harvested repeatedly while SCT and SNFT were harvested at the end of the season (3 1/2 months). Yield parameters were taken during harvesting. Construction costs of three systems were calculated for 1000 ft 2 of area.' Construction of bins and structure establishment in DFT system was comparatively expensive than polythene pots or plastic pots used in SCT. Timers and water pumps were additional

A SIMPLIFIED NUTRIENT FILM TECHNOLOGY FOR SEED POTATO 201 costs for establishing nutrient circulating systems for DFT and SNFT. Circulating methods were not used in substrate culture and drip irrigation system is considered as an applicable automated method. Planting, fertigation and watering, daily inspections, second media application, harvesting, sterilizing, cleaning and labour costs were considered for whole cropping season. Data were analyzed using analysis of variance (ANOVA) using SAS 9.1 computer package and treatment means were separated using Duncan multiple range test at p< 0.05.

RESULTS AND DISCUSSION

Average relative humidity and temprature inside the poly-tunnel during the cropping period was 63 % and 26 °C, respectively. Fairly high temperature and low humidity were observed during the experimental period compared to conventional potato growing seasons at RARDC Bandarawela .

Growth and yield performances of systems: Plants in DFT and SNFT produced significantly higher number of tubers compared to the conventional geoponic techniques. The mean tuber number and weight was not significantly different in SNFT and DFT (Table 1).

Table 1. Growth and yield characters of potato plants grown in different techniques. Technique Tuber yield / Tuber Average Root dry Shoot dry Shoot/ plant weight(g) / tuber weight weight (g)/ weight(g)/ Root plant (g) plant plant ratio SNFT 21.5 b 91.8 ab 4.3 b 6.7 a 9.3 a 4.3 ab SCT 8 c 78.0 c 9.7 a 5.8 ab 8.9 ab 4.1 ab DFT 30 a 123.0 a 5.1 b 5.8 ab 9.5 a 4.6 a CV % 22.7 25.4 13.5 18.2 18.5 16.4 Means with the same letter are not significantly different at P=0.05. SNFT=simplified nutrient film technique; DFT=deep flow technique; SCT=substrate culture technique.

Means of the tuber number and weight per plant was significantly different among techniques. Per plant yield was significantly higher in DFT followed by SNFT. Average tuber weight was significantly higher in substrate culture while the number of tubers was less (Jayathilake et al., 2008). Dry weight of shoots and roots of the plants grown in different systems were not significantly different among the treatments. Therefore shoot to root ratio of all plants were not significantly different with each other. It revealed that, threefold high seed multiplication rate than geoponic system can be achieved using SNFT.

202 RAJAPAKSE et al. Table 2. Yield characters of potato plants grown in farmer SNFT systems at different locations. Location Tuber yield / Tuber No. of stolons Tubers/ weight(g)/plant 1,00ft 2 plant Halpe 24.3 102.3 8 4704 Kappetipola 18.5 88.2 5 3552 Labukale 22 123 13 4224 Averages 21.6 104.5 8.6 4160

Yield of farmer managed SNFT in different locations revealed that, average 4,160 tubers/100 ft 2 can be harvested from SNFT (Table 2). Sound crop management practices with economic and agronomic means ensure higher yields enabling to reduce the production cost (Jayathilaka et al., 2008).

Table 3. Economic analysis of hydroponic seed production systems in an area of 1,000 ft 2 Operation SNFT (Rs) SCT (Rs) DFT (Rs) Construction cost 30,000.00 20,000.00 210,000.00 If applying automated methods 53,800.00 25000.00 53,800.00 Totall capital cost 83,800.00 45,000.00 2,63,800.00 Total running cost 32,220.00 23,750.00 44,682.00 Total tuber yield of 1000 ft 2 40,000 10,000 37,500 Gross income(Rs) (Rs.6.00/tuber) 240,000.00 60,000.00 225,000.00 Cost benefit ratio 7.4 2.5 5.0

SNFT=simplified nutrient film technique; DFT=deep flow technique; SCT=substrate culture technique.

When comparing only the construction costs of main structure, SNFT is 68 % cheaper than DFT in order to low material and labour costs. Expertise knowledge is needed to construct DFT while farmers can construct SNFT themselves. Due to low requirement of media solution and labour, running costs of SNFT was less than DFT (Table 3). SNFT gave more tubers in harvesting due to higher plant density compared to other two systems. Gross income was higher in SNFT and it has given higher value for cost benefit ratio and it was 48 % increment of DFT (Table 3). It was revealed that application of SNFT for seed potato production is more economically advantageous for G 0 seed production. By removing of polythene and mesh after harvesting, beds of SNFT can be used for another crop. It is more advantageous for a farmer.

CONCLUSION

SNFT is 68 % cheaper than DFT in initial construction and constructions could be done conveniently by farmers without using expertise knowledge. More than 400 tubers/100 ft 2 can be harvested and it is 7 % superior to DFT. Cost benefit ratio of SNFT is 48 % increment from DFT. It was concluded that, SNFT is technically sound and economically advantageous method for seed potato production.

A SIMPLIFIED NUTRIENT FILM TECHNOLOGY FOR SEED POTATO 203 ACKNOWLEDGEMENT

Authors wish to express their sincere thanks to the Deputy Director of RARDC, Bandarawela for his encouragement given for this study and Sri Lanka Council for Agriculture Research Policy for providing funds to carry out the initial experiments and KOPIA for farmer trial evaluations.

REFERENCES

Agstat, 2015.Department of Agriculture, Peradeniya. Correa R.M, J.E.B.P. Pinto, V. Faquin, C.A.B.P. Pinto and E.S. Reis, 2007. A comparison of potato seed tuber yields in beds, pots and hydroponic systems. Plant Biology Department, Montana State University, Bozeman-Montana, United States Jayathilaka. P.K.S, S.M. Wijesundara, A.M.S.R. Atthanayaka and A.B.S. Balasooriya, 2008. On farm production of quality seed potato in Badulla District. International potato symposium: 71-86p Kularathna R.J.K.N , K.V.D.I. Perera, U.I. Sangakkara, C. Premarathna, and E.R. Chandimal, 2008. An aeroponic system to address seed potato (Solanum tuberosum L.) Issues through hydroponically produced mini tubers: an economic analysis, International potato symposium: 71-86. Mazeen A.C.M, M.M. Nugaliyadda, M.A.G.C.N. Premarathna, R.S.R.M.A.D Rathnayaka, 2008.Growth and yield performance of potato (Solanum tuberosum L.) pre basic seeds produced through repeated harvesting method using different soil less cultivation system. International potato symposium: 111-11.

Short Communication Annals of Sri Lanka Department of Agriculture 2016. 18: 204 - 206

PROPERTY RIGHT VALUE ESTIMATION OF PADDY VARIETIES PRODUCED BY THE DEPARTMENT OF AGRICULTURE

K.G.C.D.B. WIJESINGHE, V.D.N. AYONI AND T.H.C.S. PERERA

Socio Economics and Planning Centre, Peradeniya, Sri Lanka

INTRODUCTION Department of Agriculture (DOA), Sri Lanka has developed more than 50 rice varieties during the past 30 years through its satellite research centers. Some of these varieties are popular among farmers while some are not. Significant percentage of the DOA budget is allocated to research every year while this study intends to value the rice varieties developed by DOA. Until, 1940’s traditional rice varieties were widely cultivated. At that time there was a total production of 0.25 million mt, extent of 0.39 million ha, and an average production of 0.65 t/ha (Abeysiriwardena, 2003). At present the annual production is 3.4 million mt, sown extent is 0.96 million ha, and the average yield is 4.2 t/ha. Currently, the DOA is lacking varietal valuation studies, and thus this study is expected to meet that requirement.

METHODOLOGY

Rice varieties were valued at market price. Since there is no direct market value available, contingency method was used. A backward calculation was done from the farmer level to breeder level, and the present value was calculated at a discount rate of 5 %. Secondary data on variety based annual cultivation extent for 2014 (Rice Research and Development Institute) and farm-gate price of paddy (Department of Census and Statistics), released year of rice varieties (Recommended new crop varieties and FAO rice information, 2002) were used for the analysis.

Analytical framework/Valuing intangible assets: LKAS 38 which is the accounting standard related to intangible assets defines in the paragraph 9 as “scientific or technical knowledge, design and implementation of new systems, licenses, intellectual property, market knowledge and trade mark” and paragraph 10 states such item should have identifiable, control over the resources and existence of future economic benefits. Most of the varieties developed by DOA are in accordance to the above criteria. RESULTS AND DISCUSSION

Of the early varieties of new improved varieties (NIV- the 2 nd stage of the hybridization programme produced an improved set of new varieties with dwarf plant type, good level of resistance to lodging and prevalent diseases and high yield potential (10t/ha) in the late 1960’s were referred to as New Improved Varieties (NIV) (Senadhira, 1980)), the top five popular varieties were Bg 352, Bg 300, At 362, Bg 94-1 and At 307 (Table 1). At 362 was one of the major popular varieties more than 30 years old. Among newly released varieties in near past Bg 358 was the most popular variety (Table 2).

PROPERTY RIGHT VALUE ESTIMATION OF PADDY VARIETIES 205 Table 1. Most popular varieties -released year more than 20. Variety Years after Annual extent Crop PV at 5% Seeds PV at 5% released (ha) level (bn) level (bn) Bg 352 23 185,273 262 17 Bg 300 28 177,178 105 7 At 362 >30 91,420 20 1 Bg 94-1 >30 76,295 16 1 At 307 >30 32,583 9 0.5 At 308 >30 26,053 5 0.3 Bg 379 -2 >30 20,889 5 0.3

Note: PV - present value; bn - Billion.

Table 2. Most popular varieties- released years less than 20.

Variety Years after Annual Crop PV at 5% Seeds PV at 5% level eleased extent (ha) level(bn) (bn) Bg 358 16 112,043 275 18 Bg 359 16 45,210 111 7 Bg 360 16 40,912 91 6 Bg 357 18 34,482 70 5 Bg 366 6 9,661 32 2 Bg 305 16 8,962 18 1

Among the new and old released NIV varieties, older varieties are still popular among the farmers but according to the Kotlers’ Product Development Cycle (Kotler, 2000) they are at milking or declining phase. Even the new varieties are less popular among farmers, most of them are at introductory phase and some of them such as Bg 358 and Bg 359 are at growth stage. Yet, other than Bg 366 none of the new released varieties were cultivated by farmers. The non popularity must be addressed separately with high concentration. Some of the early released NIV varieties such as Bg 750, Bg 34-8, Bg 301, Bg 34-6, Bw 363, Bw 367, Ld 368, Bg 11-11, Bg 454 were very less popular and at their last few years at the field. Paddy varieties as such 94-2, Bw 451, Bg 745, Bg 3-5, Bg 407 were some of these varieties that were substituted by farmers with new varieties.

The estimations revealed that the DOA seed paddy possessed above 72 billion rupees of net worth at its Present Value (PV) and the PV of paddy accounted for 1,097 billion rupees (Table 3). Therefore, the Department is under pricing their product for providing subsidy for the industry and it is 6.5 % of the market value.

Table 3. Summary: Total market value and PV. Type Estimated Present Value (PV) of the Estimated Present Value (PV) of DOA seeds crop/ paddy (Rs.bn.) (Rs.bn). NIV 1,096 72 OIV 0.453 0.012 Traditional 0.276 0 Local 0.166 0

206 WIJESINGHE et al.

CONCLUSION

The Department of Agriculture released rice varieties and seed paddy posses PV of 1 trillion rupees and 72 billion rupees, respectively. A royalty fee can be charged on the each sale of seed paddy 2 Rs. Per kg and establish a research fund under RRDI to facilitate future research activities. Thus, the expected collection per annum is Rs. 23 million.

REFERENCES

Abeysiriwardena, D.S. de Z. 2003. Rice varietal improvement for future challenges. In: Rice congress 2000. eds, D.S. de Z., Abeysiriwardena, D.M.N. Dissanayake, L. Nugaliyadde. Department of Agriculture, Sri Lanka. 87-93 p. CA Sri Lanka. 2015. Sri Lanka accounting standard LKAS 38. Available from: http://www.casrilanka.com . [Accessed 25 October 2015]. Socio Economics and Planning Centre. Various. Cost of Cultivation of agricultural crops. Socio Economics and Planning Centre, Department of Agriculture, Peradeniya. FAO rice information. 2002. FAO. Rome, Italy. Vol. 3. 177 p. Kotler, P. 2000. Principles of Marketing, Product life cycle: characteristic, strategies and objectives, Millennium edition, Pearson Education, India.

Short Communication Annals of Sri Lanka Department of Agriculture 2016. 18: 207 - 211

SCREENING OF CHILLI (CAPSICUM ANNUM L.) PARENTAL LINES FOR CHILLI LEAF CURL VIRUS, BACTERIAL LEAF SPOT AND ANTHRACNOSE DISEASES

W.M.K FERNANDO, W.M.S.D.K.WIJERATHNE, D.M.K. DISSANAYAKE

AND H.M.S.N. HERATH

Field Crops Research and Development Institute, Mahailluppalama, Sri Lanka

INTRODUCTION Chilli ( Capsicum annuum L.) is the most important commercially grown vegetable and the second largest commodity in the international trade as a condiment. The area under green chilli cultivation and the annual production in Sri Lanka were around 13,978 ha and 71,767 t, respectively in the year 2014 (Agstat, 2015). Chilli yield is highly affected by diseases, which is the major constrain in Chilli production. Studies have shown that biotic stress conditions and its secondary effects are the main reasons behind the low extent of cultivation and poor yield levels reported in yala season in the Dry zone (Gunawardana, 2002). Leaf curl virus (CLCV) is the most devastating disease reported from all the chilli growing areas in Sri Lanka, and it causes a serious yield loss (Rajapakse et al, 2003). Anthracnose caused by Colletrotricum spp. and bacterial leaf spot (BLS) caused by Xanthomonas campestris are also problematic diseases in chilli cultivation especially in moist environmental conditions (Black et al., 1991). Yield loss of CLCV and anthracnose may reach up to 100% (Akhter et al., 2009; Shankar et al., 2014) and 20% by BLS (Sanogo et al., 2008). Though there are chemicals and other control methods available, identifying resistant lines are the most economical and sustainable strategy to minimize the damages due to diseases. Hence, this experiment was conducted with the objective of identification of resistant/tolerant chilli parental lines for CLCV, Anthracnose and BLS diseases.

MATERIALS AND METHODS

A field experiments were conducted at Field Crops Research and Development institute, Mahailluppallama during yala 2015 and maha 2015/2016. Twelve parental lines developed by chilli breeding program were screened with the recommended varieties, namely MI 2 and MICH 3. Parental lines used in this experiment were

208 FERNANDO et al. developed through generation advancement and selection for better agronomic traits, low pests and disease incidences. Nurseries were established separately in plant pathology field to obtain the seedlings. Experiments were conducted in randomized complete block design with three replicates. Thirty five days old seedlings were transplanted in a 4.5 m x 1.8 m plot with 45cm x 60cm spacing. Fungicides and insecticides were not applied during experimental period and other agronomic practices were followed as recommended by the Department of Agriculture, Sri Lanka.

Data collection Disease severity index (DSI) was calculated using the equation given below for each genotype based on symptomology given in 0-4 scale for CLCV (Table 1) and 0-9 scale (Table 2) for BLS infections.

Total sum of numerical rating DSI x 100 Number of Observations x Maximum disease rating

Table 1. Disease Rating scale used for CLCV. Disease rating scale Percentage infection 0 Free from viral 1 1-10% canopy showing symptoms 2 11-20% canopy showing symptoms 3 21% - 50% canopy showing symptoms 4 >50% canopy showing symptoms

Table 2. Disease Rating scale used for BLS.

Disease rating scale Percentage infection 0 Free from disease 1 1-10% canopy showing symptoms 3 11 -20% canopy showing symptoms 5 21% - 50% canopy showing symptoms 7 50% -75% canopy showing symptoms 9 >75% canopy showing symptoms

Screening of anthracnose disease was done in the laboratory under artificial inoculation for the detached ripened pods as described by Montri et al. (2009). Table 3 shows the disease rating scale for anthracnose screening. The data were analyzed using Statistical Analysis Software (SAS). CATMOD procedure was used to analyze data after the normality test. Normality test was run for the DSI values calculated using disease

SCREENING OF CHILLI PARENTAL LINES FOR DISEASES 209 counts of the trial. Since all the sets of data did not show normal distribution (Shapiro - Wilk test statistics p< 0.05), nonparametric approach in the SAS analysis using CATMOD procedure was adopted.

Table 3. Disease Rating scale u sed for anthracnose. Disease rating scale Resistant levels Percentage infection 0 HR, Highly resistant No infection 1 R, Resistant 1-2% of the fruit show necrotic lesion or a large water soaked lesion surrounding the infection site 3 MR, Moderate resistant 2-5% of the fruit area show necrotic lesion, acervuil may be present, or water soaked lesion up to 5% of the fruit 5 MS, Moderate 5-15%surface of the fruit area shows necrotic Susceptible lesion, acervuil may be present, or water soaked lesion up to 25% of the fruit 7 S, Susceptible 15-25% of the fruit area shows necrotic lesion with acervuil More than 25% of the fruit area shows 9 HS, Highly susceptible necrotic lesion often encircling of the fruit; abundant acervuil RESULTS AND DISCUSSION

Parental lines MICH PL 08, MICH PL 09 and MICH PL 42 lines show significantly low DSI values for CLCV compared to both the check varieties in both seasons (Table 4). Hence, these parental lines could be a good source for breeding programme to develop CLCV tolerant varieties. MICH PL 42 is showing low disease reactions compared with MICH PL 08 and MICH PL 09 though there is no significant differences according to the comparisons.

The field screening for anthracnose and BLS could be done only in maha 2015/16 season as the disease were prevailed only in that season. According to Table 5, MI 2 shows a low DSI value for anthracnose among the two check varieties. Compared to MI 2, none of the parental lines showed significant difference in respective DSI value. The parental line MICH PL 18 showed the lowest DSI value for anthracnose among the parental lines, and was significantly different from MICH 3 check variety. MICH PL 08 and MICH PL 09 lines showed significant differences with both the check varieties showing low DSI values for BLS. These two lines were not significantly different from each other for BLS, MICH PL 09 line showed the lowest DSI value.

210 FERNANDO et al. Table 4. Disease severity index of chilli parent lines against Leaf curl virus. Disease severity index Reaction Yala 2015 Maha 2015/16 MICH PL 08 7.1 bJ 15.3 bJ MR MICH PL 09 9.2 b-t 12.7 bJ MR a,t a,t MICH PL 16 37.1 44.2 MS bJ b,t MICH PL 18 40.0 29.2 MS bJ a,t MICH PL 51 42.5 42.0 MS MICH PL 66 10.4 bJ 35.2 b>t MS MICH PL 21 35.0 a>t 27.8 bJ MS MICH PL 80 35.8 a>t 33.8 b,t MS MICH PL 75 39.2 a>t 51.6 at S bJ a,t MICH PL 83 7.5 42.5 MS MICH PL 26 45.8 bJ 16.9 bJ MS MICH PL 42 2.9 b-t 1.5 bJ R MICH 3 27.5 t 41.4 t MS MI 2 29.5 a 53.3 a S Note: Within each column comparison were done with check varieties. The values followed by different letter or symbol superscript are significantly different (P<0.05) where Symbol indicates the comparison with MICH 3 and the letter indicates the comparison with

MI 2. Table5. DSI of chilli parent lines against BLS and ant hracnose in 2015/16 maha season. Parent line BLS Anthracnose Disease severity Reaction Disease severity Reaction index index b>t MICH PL 08 MR 20.7 S MICH PL 09 6.7 bJ MR 15.9 at MS aJ b,t MICH PL 16 20.0 MR 24.0 S MICH PL 18 16.7 aJ MR 8.7 aJ MS a,t b,t MICH PL 51 31.7 MS 20.0 S MICH PL 66 28.3 a>t MS 14.8 a>t MS MICH PL 21 53.3 b,i S 12.2 a>t MS MICH PL 80 15.0 aJ MR 16.7 a>t S a>t a,t MICH PL 75 30.0 MS 23.4 S MICH PL 83 26.7 aJ MS 20.5 b>t S a,t b,t MICH PL 26 38.3 MS 26.0 S MICH PL 42 33.3 a,t MS 18.5 bt S MICH 3 38.3 t MS 19.5 t S a MI 2 23.3 MR 12.6 a MS Note: Within each column comparison were done with check varieties. The values followed by different letter or symbol superscript are significantly different (P<0.05) where Symbol indicates the comparison with MICH 3 and the letter indicates the comparison with MI 2.

CONCLUSIONS

MICH PL 08, MICH PL 09 and MICH PL 42 lines are good sources for CLCV resistant breeding programme. MICH PL 08, MICH PL 09MICH PL 16, MICH PL 18 and MICH PL 80 showed tolerant reactions for BLS disease. All the screened lines were moderately susceptible or susceptible for chilli anthracnose.

SCREENING OF CHILLI PARENTAL LINES FOR DISEASES 211 REFERENCES

Agstat. 2015. Pocket book of Agricultural Statistics. Volume ix. Socio-Economic and Plannig Centre, Department of Agriculture, Peradeniya, Sri Lanka. 16 p. Akhter, A., Qazi, J., Saeed, M. and Mansoor, S. 2009. A Severe Leaf Curl Disease on Chilies in Pakistan is on Associated with Multiple Begomovirus Components. National Institute for Biotechnology and Genetic Engineering (NIBGE), Pakistan. 93: 962. Black, L.L., Green, S.K., Hartmon, G.L. and Poulos, J.M. 1991. Pepper disease: A Field Guide. Asian Vegetable Research and Development Centre, AVRDC publication No. 91-347, 98 pp. Gunawardana, K.N.C. 2002. Assessment of Yield loss due to thrips (Thysanapthera: Thripidae) in Chilli. 2000: Annuals of the Sri Lanka Department of Agriculture. 4:275:280 Montri, P., Taylor, P.W.J. and Mangkolporn, O. 2009. Pathotype of Colletrotricumcapsisi, the Causal Agent of ChilliAntracnose, in Thailand. The American Phytopathological Society Journals 93:17-20. Rajapakse, R.G.A.S., W.A.P.G. Weerarathna and M.G.D.L. Priyantha. 2003. In Fifty Years of Research 1950-2000: Review of Past Findings of Agricultural Research at Mahailluppallama. Eds. By P.B. Dharmasena, H. Samarathunge and M.S. Nijamudeen. Field Crops Research and Development Institute, Department of Agriculture, Mahailluppallama, Sri Lanka. Sanogo, S., Zapata, R., Browning, P.E., Fedio, W.M., Liess, L. and Clary, M. 2008. Characterization of 2000: Bacterial Leaf Spot of Chile Pepper in New Mexico. New Mexico state university, Mexico. Shankar, R., Harsha, S., Bhandary, R. 2014. A practical guide to identification and control of pepper diseases. Tropica seeds private limited, India. 11 p.

Short Communication Annals of Sri Lanka Department of Agriculture 2016. 18: 212 - 215

INVESTIGATION ON BROWN SPOT DISEASE OF RICE (ORYZA SATIVA L.) IN SRI LANKA

H.N.S. FERNANDO 1, Y.J.P.K. MITHRASENA 1, J.N.SILVA 1 AND A.A.W.P.ADIKARI 1

Regional Rice Research and Development Centre, Bombuwela, Sri Lanka

INTRODUCTION

Brown leaf spot of rice caused by Bipolaris oryzae is one of the major fungal diseases of rice which occurs in almost all rice growing areas in the world. Bipolaris oryzae causes seedling blight, necrotic spots on leaves and seeds, and also grain discoloration. Severely infected seeds may fail to germinate. Seedling blight is common on rice in both rainfed lowlands and uplands. Under these rice production eco-systems, brown spot can be a serious disease causing considerable yield loss. In history, the Bengal famine of 1942 was attributed to brown spot (Mew and Gonzales, 2002). Mithrasena et al., (2012) isolated several pathogens from brown spot infected rice leaves and discolored grains in Sri Lanka. They were Fusarium spp, Curvularia spp, Helminthosporium spp., Alternaria spp., Nigrospora spp. and Sarocladium spp. During recent past some leaf spot diseases were reported in Low Country Wet Zone in Sri Lanka, especially, in Galle and Kalutara districts. Some of the paddy cultivated fields in Horana and Galle areas were abandoned due to the disease. Almost 100% yield loss was reported in some fields. Therefore, farmers had suspected that this condition was either blast or bacterial disease. They had even practiced fungicide Tebuconazole to control the disease & claimed that it did not control the disease. Therefore, this study was undertaken ascertain the causal organisms responsible for the disease and the efficacy of fungicide Tebuconazole against this causal organism.

MATERIALS AND METHODS

Sample collection and pathogen isolation: Disease samples were collected from Kalutara and Galle districts during Maha 2015/2016 season. Pathogen isolation was done at the Pathology laboratory of the Regional Rice Research and Development Centre (RARDC), Bombuwela. Pathogen was identified by morphological characters according to Mew & Gonzales,(2002). Pathogenicity was confirmed by Koch's postulates. Morphological characters viz. colour of the culture, growth rate and growth pattern of the isolates were recorded at 1 day interval up to14 days. Spore shape, colour and size were observed under light microscope.

In vitro evaluation of fungicide Tebuconazole against the causal organism of Brown Spot disease: Different fungicide concentrations, namely,100, 200, 300, 400, and 500 ppm were prepared to test the efficacy of the fungicide Tebuconazole. Sterilized 5 mm diameter filter paper disks were dipped in each fungicide concentration. Four disks were placed symmetrically on a Potato Dextrose Agar (PDA) containing in petri dishes. Five mm diameter mycelia plug obtained from

INVESTIGATION ON BROWN SPOT DISEASE OF RICE IN SRI LANKA 213 pure cultures was placed in the centre of the petri dish and incubated at room temperature (30 ± 2 0C). Each fungal isolate were replicated four times. This experiment was conducted in Complete Randomized Design (CRD). Control plates were maintained without adding fungicide dipped filter paper disks. Diameter of the colony was measured when control plate was fully covered with the pathogen and inhibition percentage was calculated. Normality test was carried out to asceratin whether inhibition percentage data follows a normal distribution, according to Anderson - Darling test (pr>0.0679) and it was found that data are normally distributed. Therefore, ANOVA (Analysis of Variance) method was used to analyze the data using SAS and mean separation was done using DMRT (Duncan Multiple Range Test).

RESULTS AND DISCUSSION

Two fungi spp., Bipolaris and Nigrospora were identified in pathogen isolation studies. Identification of fungal isolates was based on the morphological characters given by Mew and Gonzales (2002). Colony characters and microscopic observations of conidia and conidiophores in this study, suggested that isolates were similar to Bipolaris and Nigrospora spp. Therefore, it could be concluded that this disease condition could be probably due to fungal of brown spot disease. According to Mew and Gonzales (2002), Nigrospora spp. are most common in rice cultivations and considered as a saprophytes and it has only a little economic importance in rice production. There were some morphological differences observed within the isolates of Bipolaris spp. Colour of the colonies varied dark grey to greenish grey. All the colonies are zonated with white to grey margins except I-3 which was zonated very clear with white margins. Growth behaviour in the medium of growing was observed in all isolate except I-3. All isolates produced less conidia and abundant mycelia at the room temperature (30 ± 2 0C). Conidia were club shape to cylindrical, curved, and brown in colour with 4-6 pseudosepta. Colony characters and growth behaviour of the collected isolates are described in Table 1. Table 1. Description of colony charact ers and growth behaviour of isolates. Isolate Collected Colony characters Days required to Growth behaviour location reach the edge of petri dish

I-1 Aluthgama- Greenish grey with flat 07 Medium growing Dharga Town growth pattern I-2 Aluthgama- Greenish grey with flat 07 Medium growing Dharga Town growth pattern I-3 Kalutara - Dark grey with flat 10 Slow growing Katukurunda growth pattern with fluffy mycelia growth in edges I-4 Greenish grey with flat Medium growing Kalutara- 08 Bombuwela growth pattern I-5 Galle - Light Greenish grey 07 Medium growing Wewaldeniya with flat growth pattern

214 FERNANDO et al. Response of the isolates for different concentrations of the fungicide was significantly different (p>0.0001). Each isolate behaved differently in each concentration (p>0.0001). There was an interaction effect between concentration and the isolates (p>0.0004). Isolates did not behave in similar manner with the tested concentrations except 500 ppm. Behaviour of each isolate was different in different concentrations. Highest inhibition percentage was observed in 500 ppm as 90%-84.4% (Table 2). There were no significant differences (p>0.05) among the isolates at 500 ppm concentration. According to the investigation, fungicide Tebuconazole was effective for controlling Bipolaris spp. in vitro. Field experiment conducted by Mithrasena et al., (2012) has revealed that fungicide Tebuconazole was effective under field conditions when commencing application at the booting stage. Therefore, application at the correct time is a necessary pre-requisite for proper management of the disease.

CONCLUSION

Disease condition of rice cultivations in Galle and Kalutara disticts which was erroneously identified or suspected as either a blast or bacterial disease is brown spot disease caused by Bipolaris spp. and Tebuconazole was an effective fungicide to control said fungal disease condition. Thus, any outbreak of such disease symptoms in future should be carefully investigated instead of making wrong or immature decisions.

Table 2. Mean radial growth (cm) of Bipolaris spp. at different concentrations of Tebuconazole 250g L-1'

Isolate Mean radial growth of Bipolaris spp. at various concentrations of Tebuconazole 100 Inhib 200 Inhib 300 Inhib 400 Inhib 500 Inhib I nhib pp m . % pp m . % pp m . % pp m . % pp m . % Con. . % I-1 3. 5 61d 3.0 67bc 2.2 75a 1.8 80 a 1.3 85a 9.0 0.00 I-2 3.1 65b 2.9 68b 2.5 72b 2.3 74 b 1.4 84a 9.0 0.00 1-3 2.9 68a 2.6 71a 2.4 73ab 1.8 80 a 1.0 89a 9.0 0.00 I-4 3.6 60d 3.1 65c 2.5 72b 1.7 81 a 1.2 87a 9.0 0.00 I-5 3.3 63c 2.6 71a 2.3 74ab 1.5 83 a 0.9 90a 9.0 0.00 CV 1.4 1.3 1.7 2.4 4.5

(%) P (Isolate) 0.0001 0.0001 0.042 0.0022 0.44 Note: CV=Coefficient of Variation; Mean in each column followed by the same letters are not significantly different by the LSD at p=0.05.

REFERENCES

Mew, T.W. and Gonzales, P. 2002. A Hand Book of Rice Seed Borne Fungi. Science Publisher, Inc. pp 82. Mithrasena, Y.J.P.K., Silva, J.N., Adikari, A.W.P., Weerasingha, W.M.S.K., and Sumanasingha, H.P.D. 2012. Identification and management of Brown Spot and grain discolouration disease of rice in Sri Lanka. Proceedings of the

INVESTIGATION ON BROWN SPOT DISEASE OF RICE IN SRI LANKA 215 Annual Symposium of the Department of Agriculture vol 14: pp 77-86.

Annals of Sri Lanka Department ofAgriculture 2016. 18: 216 - 219

Short Communication

HEAVY METAL CONTENTS OF COMPOSTS MADE USING DIFFERENT RAW MATERIALS

S.P. GUNARATHNE 1, G.A.S.S.L. GUNATHILAKA 2 , K.A.C. KANDEMULLA 2, B. K.KANNANGARA 1, K.K.D. CHANDRASEKARA 1, A.E.MUNASINGHA 1, AND S.D.UMANGE 1

1 Regional Rice Research and Development Centre, Bombuwala 2 Regional Agricultural Research & Development Centre, Makandura, Sri Lanka

INTRODUCTION

As a requirement for intensification of agriculture at present, farmers are increasing the usage of agro-chemicals greater than ever which may escalate soil and water pollution (Kuruppuarachchi and Fernando, 1999; Aponso et al., 2003). It is therefore needed to restore soil health and adopt environmentally benign crop production systems. Organic fertilizers are introduced as an effective tool to rehabilitate the soil and thus use of compost is being promoted. The production of compost from agricultural and industrial wastes, as well as from municipal by products are an important means of recovering organic matter reflecting an essential method of healthy disposal. Generally, heavy metals are considered to be the metallic elements with a density over 5 g/cm3 (Braddy, 1985) or with an atomic weight greater than that of Fe (Pierzynski et al., 2000). Bockman et al. (1990) categorized heavy metals as metallic elements with high specific weight, often toxic to mammals. Heavy metals could be categorized into three groups according to their toxic levels i.e. Toxic (Cd) moderately toxic (Pb, Ni, Hg) and low toxic (Zn, Fe, Mn, Cu) and vulnerability of man to heavy metal toxicity is high when compared to many other animals and plants (Laggerwerff, 1972).

The heavy metals tend to accumulate in human and other animal tissues that enters to the body through the food chain can cause diseases such as heart attack, brain damage, cancer, diseases in digestive system, anemia, gout, chronic nephritis, encephalopathy etc. (Logerwerff, 1972). Cadmium is toxic to human at high levels causing neuropath logical systems and renal dysfunction. In addition the balance of other minerals such as P and Ca in the body could also be disturbed by high intake of Cd (IFDC, 1996). However, limited information is available on heavy metal contents in compost made by using different raw materials in Sri Lanka. In consideration of the ever increasing use of compost as a source of organic fertilizer for crop production it is important to determine exactly the heavy metal contents of different types of composts. Therefore, this study was aimed to determine the heavy metal contents of compost made by municipal solid waste and other common raw materials.

HEAVY METAL CONTENTS OF COMPOSTS 217 MATERIALS AND METHODS

Twenty two compost samples produced by local authorities using municipal solid wastes (MSW) were collected by the Divisions of Soil Science of Regional Agricultural Research and Development Centre (RARDC), Makandura and Regional Rice Research and Development Centre (RRRDC), Bombuwala. Sampled compost were from the units operating in Ja-Ela , Kotikaawaththa , Meerigama, Mathugama, Atthanagalla, Katana, Negombo, Beruwala, Walallawita, Agalawaththa, Bulathsinhala, Kaduwela, Horana, Bandaragama, Seethawaka, Seethawakapura, Hambanthota, Rathgama, Kotapola, Keerikulama, Pannala, Kuliyapitiya. Besides, twenty two compost samples made using plant residues and animal manure (PRAM) were collected from the RARDC, Makandura and another twenty two from household compost (HHW) producers who have attended the compost training programme at RARDC Makandura.

Samples were dried to a constant weight in an oven at 60 0C and dry matter content of manure was determined. Thereafter, samples were ground to a fine powder using a glass mortar and pestle and 1g of ground compost samples were digested with 10ml of 1:1 perchloric acid : nitric acid mixture in a fume cupboard and dissolved in water (Jackson ,1958). Aliquots of the sample extracts were analyzed for Pb, Cd, Zn, Cu, Ni and Cr contents using atomic absorption spectrophotometer (GBC 932 AB) at appropriate wave lengths. Data were analyzed using analysis of variance (ANOVA) procedure and the mean comparison was done by DMRT at p=0.05.

RESULTS AND DISCUSSION

Results revealed that the MSW compost contained significantly higher contents of Cd, Zn, Cr, Pb, Cu and Ni followed by compost made by PRAM and HHW. However contents of these metals in the MSW composts were the acceptable limit when compared that with the maximum permissible level for these metals in composts as per the SLS 2003 (Table 1). Moreover, compost made by PRAM showed significantly higher contents of metals than compost produced by HHP except for Cr. Result indicates considerably higher contents for six heavy metals in MSW composts than the others. Hence, the application of recommended rates of composts for crops is necessary to avoid the buildup of heavy metals in cultivated soils. In order to further understand the degree of the heavy metal contamination of biosphere by the application of compost, it is necessary to conduct more studies in depth in relation to analysis of composts made by different raw materials, with regard to content of organic matter, toxic compound and heavy metals, and the condition of the natural soils where the composts is spread.

218 GUNARATHNE et al. Table l.Metal contents on dry matter basis with respect to the used raw materials. Element Category of Content (mg/kg) Maximum feedstock Range Mean and SD Mode SE . permissible level(SLS)

a (mg/kg) Cd MSW 1.8 - 5.0 3.49 ± 0.838 2.90 0.1786 PRAM 2.0 - 2.9 2.57 ± 0.259 b 2.70 0.0550 10 c HHW 0.1 - 0.8 0.43 ± 0.182 0.30 0.0388 a Zn MSW 155.9 - 450.5 293.82 ± 55.37 275.50 11.8060 PRAM 46.4 - 100.5 70.05 ± 10.42 b 59.40 2.2220 1,000 b HHW 38.7 - 90.48 63.77 ± 12.64 62.54 2.6950

a Cr MSW 21.23 - 85.37 48.79 ± 12.25 45.98 2.6110 PRAM 13.85 - 31.5 22.35 ± 4.28 b 23.50 0.9120 1,000 b HHW 14.10 - 37.8 23.18 ± 16.58 24.50 3.5350

a Pb MSW 24.25 - 38.93 31.49 ± 3.11 31.25 0.6630 PRAM 11.25 - 29.54 18.51 ± 4.66 b 13.25 0.9940 250 c HHW 3.9 - 19.85 10.26±3.23 11.65 0.6890

a Cu MSW 0.10 - 3.6 2.02 ± 0.63 2.40 0.1340 PRAM 0.28 - 2.9 1.37 ± 0.40 b 1.40 0.0850 400 c HHW 0.1 - 0.9 0.42 ± 0.17 0.25 0.0360 a Ni MSW 20.65 - 56.97 39.45 ± 8.64 31.89 1.8420 PRAM 5.5 - 21.35 12.57 ± 4.38 b 5.90 0.9330 100 c HHW 2.4 - 19.54 9.92 ± 4.71 16.54 1.0040

SD=Standard deviation; SE=Standard error of the mean; Values are mean ± SD of 22 samples of compost, analyzed individually in triplicate. Mean values in the same column followed by the same superscript letters are not significantly different at 0.05 level probabilities by DMRT.

Metallic contaminants may occur not only from municipal solid wastes but also from animal manures, sewage sludge and pesticides (Azita Behbahaninia and Ahmad Mirbagheri, 2008). Furthermore, when metals have been bound to the soil, the pH, redox potential, and organic matter content will influence the tendency of the metal to exist in ionic and plant available from (Alina Kabata- Pendias, 2011). Metal uptake by plants depends on the bioavailability of the metal in the water phase, which in turn depends on the retention time of the metal, as well as the interaction with other elements and substances in water (Kabata- Pendias and Adriano, 1995). Hence, the metallic compounds are not degraded during composting but may be converted in to organic combinations that have less bioavailability than mineral combinations of the metals (Barker and Bryson, 2002). Therefore, further information will be required to determine the long term or short term effect of application of different types of composts in to the soil.

CONCLUSIONS

MSW composts contained the highest amounts of Pb, Cd, Ni, Cr Zn and Cu in comparison to others. However, the amounts of heavy metals in the tested types of composts were far lower when compared to the acceptable levels of the heavy metals in composts determined by the Sri Lanka Standards Institution (SLS, 2003).

HEAVY METAL CONTENTS OF COMPOSTS 219 ACKNOWLEDGEMENTS

The authors wish to acknowledge Dr. J. D. H. Wijewardhana, Addtional Secretary (Development), Ministry of Agriculture for the giving financial assistance to develop the soil laboratory of RARDC Makandura and to Professor (Mrs.) S. P. Indrarathna, PGIA Peradeniya for the valuable guidance provided during this study.

REFERENCES

Barker, A.V. and Gretchen M. Bryson. 2002. Bio remediation of heavy metals and organic toxicants by composting. The Scientific World Journal 2, 407-420. Behbahaninia,A. and Seid Ahmed Mirbagheri. 2008. Investigation of heavy metals uptake by vegetable crops from metal contaminated soil World academy of science, Engineering and Technology 43: 56. Brady, N.C.1985. The Nature and Properties of Soils. Macmillan Publishing Company, New York. 750p IFDC. 1996.The basics of Zn in crop production. Technical Bulletin T-43, Intrnational Fertilizer Development Centre, Muscle Shoals, Alabama,USA, 19p. Jackson, M.L. 1958 soil chemical Analysis. Constable and Company Ltd. London. 498p. Kabata-Pendiyas, A. and F. Pendiyas. 1992. Trace Elements in soils and plants, 2 nd Ed, CRC Press Inc., Florida. 365p. Kuruppuarachchi, D.S.P. and W.A.R.N. Fernando. 1999. Impact of agriculture on ground water quality: Leaching of fertilizers to ground water in Kalpitiya Peninsula. Journal of soil Science Society of Sri Lanka. Vol. 11.1999 Lagerwerff, J.V. 1972. Lead, Mercury and Cadmium as Environment Contaminants. In: Micronutrients in Agriculture. Soil Science Society of America, Inc., Madison, Wisconsin, Pp.596-636 Pierzynski,G.M., Sims, J.T. and G.F. Vance.2000.Soils and Environmental Quality. 2 nd Ed., CRC Press LLC, Boca Raton, Florida. SLS 2003. Specification for Compost From municipal solid Waste and Agricultural Waste.sls 1246,Sri Lanka Standards Institution, Colombo, Sri Lanka,11p Wijewardana, J.D.H. and S.P. Gunarathne. 2004. Heavy Metal Contents in Commonly Used Animal Manure. Annals of the Sri Lanka Department of Agriculture. 6:245-253.

Annals of Sri Lanka Department ofAgriculture 2016. 18: 220 - 219 Short Communication

EFFECTIVENESS OF BLACK SOLDIER FLY LARVA (HERMETIA ILLUCENS) IN SOLID WASTE MANAGEMENT AND KITCHEN WASTE COMPOSTING

D.M.P.S. DISSANAYAKE 1 , G.D.R. SILVA 2 , W.J.S.K. WEERAKKODY 2 , K.A.C. KANDEMULLA 1 AND H.M.S.K. HERATH 1

1 Regional Agriculture Research and Development Centre, Makandura, Sri Lanka 2 Faculty of Agriculture and Plantation Management, Wayamba University of Sri Lanka, Makandura, Sri Lanka

INTRODUCTION

Solid Waste Management (SWM) is a fast growing urban environmental issue in Sri Lanka. There are several methods to produce compost such as Vermi composting, Cockroach composting, Bokashi, Compost tea etc. Composting with worms and grubs is a known method of organic waste management. Currently Black soldier fly larvae (BSFL) based composting become new approach in the world. Hermetia illucens is a common fly of the Stratiomyidae family who has complete life cycle with four stages. BSF do not have functional mouth parts; therefore they do not bite nor feed. Adult not be regarded as unsanitary or a vector of diseases (Leclercq, 1997). The female black soldier fly deposits a mass of about 500 eggs in decaying matter such as dung, carrion, garbage and other organic waste (Larde, 1990). Vastly BSFL are used to reduce manure accumulation and harvested pre-pupae can be used as an animal feed (Newton et al. , 1977).

BSFL composting system is more suited for urban households as it is capable of giving acceptable solutions to several problems that associated with conventional compost bins. They are controlling of house fly (Musca domestica) other than the bioconversion of organic waste material (Sheppard 1983; Bradley and Sheppard, 1984) and it is usually not a pest and not attract to human habitation or foods. Due to high efficiency, fresh material conversion is extremely fast and it reduces production of bad odour to a minimum. BSFL is able to consume diets with fat contents (Barry, 2004) and these benefits include reduced green house gas emissions from avoided landfill emissions, decreased commercial fertilizer usage, increased soil carbon storage and decreased soil erosion. This study was to investigate efficiency of BSFL in terms of waste reduction ability and quality of compost produced by them using commonly available solid waste. MATERIALS AND METHODS

This study was carried out at the Regional Agriculture Research and Development Centre, Makandura, in 2015 Yala season. BSFL were collected from Makandura research field and multiplied. BSFL with average length of 1 cm were used to add 5 kg of selected waste materials as T1- vegetable stuff + BSFL, T2 - kitchen

EFFECTIVENESS OF FLY LARVA IN SOLID WASTE MANAGEMENT 221 waste + BSFL, T3 - ‘Pilisaru’ material + BSFL, T4 - vegetable stuff and T- 5 cattle manure + plant materials as vermin composting with earth warms (Easinia sp. ). The treatments were arranged in a Complete Randomized Design (CRD) with three replicates. Plastic containers of 18L volume were prepared providing drainage holes covered with a mesh at the bottom.

Collected data were weight of decomposing materials at weekly intervals during decomposing, temperature inside the bins, mean daily temperature, time taken for complete decomposing and the weight of decomposed material, final weight sieved by 4 mm mesh. Sensory evaluation was done with 20 people (No odour, Moderate odour, High odour). Completely decomposed samples were used for nutrient analysis as organic carbon content (Walky-black method), total Nitrogen (Kjeldahl method), available Phosphorus (using spectrophotometer), available Potassium (flame photometer), pH (1:1 soil: water according to McLean, 1982) and Electric Conductivity (1:5 water). A Pot experiment was conducted to assess the suitability different compost materials growing leafy vegetable “Mukuwenna” (Alternanthera sessilis) as a CRD design and selected treatments were T1 - only top soil, T2 - top soil: normal compost, T3- top soil : BSFL compost and T4 - Top soil : Virmy compost. Harvests were collected in one month intervals. The data were statistically analyzed by using SAS 9.2, (2009) statistical software and means were compared using DMRT.

RESULTS AND DISCUSSION

The highest weight reduction as 87.2% was obtained in kitchen waste + BSFL after four weeks and final weight was 638.3 g from initial weight. Pilisaru material + BSFL, obtained the lowest weight reduction 51.1% after ten weeks with final weight of 2.45 kg. The highest composting efficiency was obtained in vegetable stuff+ BSFL (57.66%) while lowest value was obtained in vegetable stuff only as 18.65. As BSFL chew down waste into uniform small particles T1, T2 and T3 showed higher composting efficiency than the control (T4).

BSFL with Vegetable stuff and BSFL and Kitchen waste gave high potential for avoidance of waste segregation through higher rate of weight reduction. As Pilisaru material + BSFL contained more dried leaves which were unable to break down due to high cellulose content. Sensory evaluation showed 85% - no odour in vermin compost, 80% - no odor in Pilisaru composting, 75% - no odour in vegetable stuff composting and 70% - moderately odor in kitchen waste composting with BSFL. According to Sheppard 1983; Bradley and Sheppard (1984), odour reduction may be due to ability of BSFL to suppress bacterial growth and control oviposition and development of house fly (Musca domestica) which is a critical issue of house hold compost bin.

222 DISSANAYAKE et al.

Figure 1. Weight loss of raw materials of compost with time T1=Veg + BSFL; T2=Kitchen waste + BSFL; T3=Pilisaru material + BSFL; T4=Vegetable stuff only.

The highest N % in compost showed as 3.59 and 3.88% in Kitchen waste + BSFL and Vermi compost respectively which have exceeded the N % of SLS compost standard. Further veg. stuff + BSFL showed low total N than Veg. stuff only. Nitrogen content in dairy manure was reduced probably due to the reduction of larval biomass according to Myers et al. (2008). Among treatments where BSFL were used T2 showed the highest N content as 3.59%. Both in Vermi- compost and kitchen waste + BSFL compost can be recommended as nitrogen rich sources (Table 1).

Table 1. Nutrient analysis of compost (Dry weight basis). N (%) Organic carbon Treatment pH EC P2O5 (%) K2O (ms/cm) (%) (%) a a bc ab c T1 Vegetable stuff + BSFL 9.91 12.90 1.81 b 0.84 1.38 41.42 T2 Kitchen waste + BSFL 5.89 e 11.59 a 3.59 a 1.17 ab 0.88 b 59.43 b T3 Pilisaru material + BSFL 7.09 d 5.80 b 2.09 b 0.62 c 1.90 a 32.12 c T4 Vegetable stuff only 9.09 b 3.43 c 2.09 b 1.19 ab 0.92 b 38.24 c T5 Vermi compost 8.03 c 1.03 d 3.88 a 1.39 a 0.42 c 154.06 a SLS standards 6.5-8.5 >1.0 > 0.5 > 1.0 20 LSD 0.44 0.41 0.24 0.23 0.25 0.30 Means followed by the different letters in each column are significantly different.

Veg. stuff + BSFL compost showed significantly lower value for available P (0.84%) than decayed veg. stuff, but treatments were not significantly different from each other. BSFL + kitchen waste and Veg stuff showed high percentages of P but not significantly different with the Vermi- compost. Pilisaru material + BSFL compost showed the highest percentage of potassium as 1.9%. There were significant differences in pH among all treatments and it proved that BSFL is capable of decreasing concentrations of organic alcohols and acids significantly while processing micro aerobic fermentation leachate (Green and Popa, 2012). As BSFL is capable of reducing acidity, they can be effectively used for compost production with high acidic substrates. When compared the yields of leafy vegetable “ mukunuwenna ”, BSFL, vermi and normal compost gave more or less equal yields which were not significantly different.

EFFECTIVENESS OF FLY LARVA IN SOLID WASTE MANAGEMENT 223 CONCLUSIONS

Waste reduction within short period of time (1-1% months) can be done by using BSFL for various sources of organic matter except rough plant structures that contain more cellulose. Though traditional composting works well with yard waste, BSFL can effectively convert kitchen waste into compost. Therefore BSFL can be an appropriate solution for solid waste management/ kitchen waste management due to its high rate of waste reduction, low time period for decomposing, limited space requirement and low level of odour generation. REFERENCES

Barry, T. 2004. Evaluation of the Economic, Social and Biological Feasibility of Bioconverting Food Wastes with the Black Soldier Fly, University of North Twxas, UNT Digital Library. Bradley, S.W. and Sheppard, D.C. 1984. House Fly Oviposition Inhibition by Larvae of Hermetia illucens , the Black Soldier Fly. Journal of Chemical Ecology, 10, 853-859. Green, T. and Popa, R. 2010. A Simple Assay for Monitoring Cellulose in Paper-Spiked Soil Journal of Polymer and the Environment, 18, 634-637. Hale, O.M. 1973. Dried Hermetia illucens Larvae (Diptera: Stratiomyidae) as a Feed Additive for Poultry. Journal of the Georgia Entomological Society , 8, 16-20. Larde, G. 1990. Recycling of Coffee Plup by Hermetia illucens (Diptera: Stratiomyidae) Larvae. Biological Waster, 33, 307-310. Leclercq, M. 1997. A Propos de Hermetia illucens (Linnaeus, 1758). Bulletin etAnnales de la Society Royale Belged’Entomologie, 133, 275-282. Myers, H.M., Tomberlin, J.K., Lambert, B.D. and Kattes, D. 2008. Development of Black Soldier Fly (Diptere: Stratiomyidae) Larvae Fed Dairy manure. Environmental Entomology, 37, 11-15. Newton, G.L., Booram, C.V., Barker, R.W. and Hale, O.M. 1977. Dried Hermetia illucens Larvae Meal as a Supplement for Swine. Journal of Animal Science, 44, 395-400. Sheppard, D.C. 1983. House fly and Lesser House Fly Control Utilizing the Black Soldier Fly in Manure Management System Using the Black Soldier Fly. Bioresource Technology. 50, 275-279. St-Hilaire, S., Sheppard, D.C., Tomberlin, J.K., Living, S., Newton, G.L., McGuire, M.A., Mosley, E.E., Hardy, R.W. and Sealey, W. 2007. Fly Prepupae as Feedstuff for Rainbow Trout, Oncorhynchus Mykiss. Journal of the world Aquaculture Society, 38, 59-67.

Annals of Sri Lanka Department of Agriculture 2016. 18: 224 - 228 Short Communication

EFFECT OF ROOT PRUNIING AND RE-POTTING AFTER GRAFTING ON GRAFTING SUCCESS, SHOOT AND ROOT GROWTH AND SURVIVAL PERCENTAGE OF DURIAN (DURIO ZEBETHINUS MURR.)

E.R.S.P. EDIRIMANNA, K.M.M.T.U.B. KANGARA, W.T.P. WICRAMARATHNE

AND H.A.K.N. HETTIARACHCHI

Fruit Crop Research and Development Station, Gannoruwa, Peradeniya

INTRODUCTION Durian is mainly propagated by using grafted plants, have a slow growth rate and bear in 5-6 years under good management conditions. Grafting of Durian is practiced for 1-2 months old seedlings as the success rate is high at this stage. However, growers complain that higher percentage of grafted plants prematurely die after transplanting in the field. Tap root of durian grow very rapidly and the length of the tap root is relatively higher compared to other fruit trees (Masri et al, 1998). Bent of tap root towards upward and damage in tip were regularly observed in grafted plants and after transplanting, most of these plants are died. Maximizing the volume of roots at the time of transplanting is critical to successful establishment. Root pruning of fruit, forest and landscape trees has been used to produce sturdier tree, development of more compact, fibrous root system and increase transplant survival and post-transplant growth (Gilman, 1992). However, there were no adequate scientific studies conducted to study the effect of root pruning of fruit crops. Therefore, this study was conducted to study the root pruning at grafting on shoot and root growth and survival rate of Durian.

MATERIALS AND METHODS

Experiment 1: Effect of root pruning at grafting and potting mixture on grafting success and shoot and root growth: Experiment was conducted as a pot experiment under shade house condition at Fruit Crop Research and Development Station, Gannoruwa (FCRDS) during 2015 -2016. Black polythene bags of 10 cm x 8 cm were filled with potting mixture of top soil: compost: sand at 1:1:1 ratio. Selected fresh seeds of similar size were placed in these bags and allowed to grow up to grafting size. Following treatments were practiced and these were arranged in a randomized complete block design with five replicates. There were 10 plants in each treatment. Trt 1=Root pruning after grafting and repotting of top soil: compost and sand 1:1:1 ratio; Trt 2=Root pruning after grafting and repotting of coir dust: compost and sand 1:1:1 ratio; Trt 3 No root pruning after grafting and repotting coir dust: compost and sand 1:1:1 ratio; Trt 4 No root pruning after grafting and repotting of top soil: compost and sand 1:1:1 ratio; and Trt 5 No root pruning after grafting and no re-potting.

EFFECT OF ROOT PRUNIING AND RE-POTTING ON DURIAN 225 Cleft grafting was practiced to 1 'A month old seedlings and Gannoruwa sweet variety was used as scion wood. All plants were uprooted after grafting and repotted according to treatments except treatment 5. In root pruning treatments, tap root was pruned leaving 1.5 cm portion of tap root. All the other management practices were as per the recommendation. Data were recorded on grafting success 3 weeks after grafting, survival percentage of grafted plants, No of leaves and shoot length at bi weekly interval. Root length was measured by uprooting randomly selected two plants in each treatment at 12 weeks after grafting. Data were analyzed by using SAS. Mean separation was done by using LSD.

Experiment 2: Effect of root pruning at grafting and age of the rootstock on survival and growth of grafted plants: Previously developed 10 months old rootstocks and 1.5 month old rootstocks were used for this study. All the plants were in top soil: compost and sand 1:1:1 ratio potting mixture. Following treatments were practiced and these were arranged in a randomized complete block design with five replicates. There were 10 plants in each treatment. Trt 1=10 months old rootstock , without root pruning after grafting and no re-potting; Trt 2=10 month old rootstock root pruning after grafting and repotting of potting mixture of coir dust: compost and sand 1:1:1 ratio; Trt 3=1.5 month rootstock, without root pruning after grafting and no re-potting; and Trt 4=1.5 month old rootstock, root pruning after grafting and repotting of potting mixture of coir dust: Compost and Sand 1:1:1 ratio Cleft grafting was practiced using Gannoruwa Sweet variety as a scion wood. All the other methods are similar to 1 st experiment. Field experiments were established using 5 months old grafted plants in three locations i.e. Gannoruwa, Wattegama and Nawalapitiya in randomized complete block design with 5 replicates. Data were collected on grafting success at 3 weeks after grafting, survival percentage, number of leaves, shoot length at biweekly interval. Root length was measured by uprooting randomly selected two plants in each treatment at 12 weeks after grafting. Data were analyzed by using SAS. Mean separation was done by using LSD.

RESULTS AND DISCUSSION

Experiment 1: Grafting success and survival rate at 12 weeks after grafting of different treatments were ranged 78- 82 % and 89- 95 % respectively and both were not statistically significant. Higher number of leaves was produced by treatment 1 and 2 compared with other two treatments at 12 weeks after grafting (Table 1). Similarly shoot length is significantly higher in root pruned treatments compared to un-pruned treatments. Root length increment is highest in treatment of root pruning and repotting of coir dust: compost and sand 1:1:1 ratio potting mixture compared to other treatments. In root un-pruned plants tap root length was increased and few secondary branches were produced. Initiation of higher number of branches up to 6 from stump of the tap root was observed in root pruned plants. Ghani (1992) showed that root pruning at the time of grafting of durian produced plants with more fibrous and compact roots and significantly increased root: shoot dry weight, plant sturdiness, stem

226 EDIRIMANNA et al. circumference and plant height compared to un-pruned plants. Root is a major vegetative organ involving in the uptake of essential nutrients and other substances for plant growth and development. Therefore, enhanced root growth and nutrient uptake are key factors in increasing shoot growth (Wieble et al. 1992). Table 1: Effect of root pruning and repotting with different media on No of leaves shoot and root growth of grafted plants. Treatments 12 weeks after grafting No of Shoot length Root length leaves increment increment (cm) (cm) a a b 1.Root pruning and repotting of Top soil: 12.5 14.2 13.1 Compost and Sand 1:1:1 ratio a a a 2.Root pruning and repotting of Coir dust : 13.8 15.6 14.8 Compost and Sand 1:1:1 ratio b b c 3.Without root pruning and repotting of 8.9 12.4 12.9 Top soil: Compost and Sand 1:1:1 ratio b c 4.Without root pruning and repotting of 9.1 12.4 12.1 b Coir dust: Compost and Sand 1:1:1 ratio b b c 5.Without root pruning and without 8.7 11.5 12.3 repotting CV% 3.2 2.8 2.5 Note: CV=Coefficient of variation; Mean in each column followed by the same letters are not significantly different at P = 0.05.

Experiment 2: Results showed that grafting success of T1, T3 and T4 are significantly higher compared to T2 treatments. Root pruning of mature seedlings showed detrimental effect to success of grafting. However, percentage survival at 8 and 12 weeks after grafting was not significantly different among different treatments (Table 2).

Root pruned and re-potting of grafted young seedlings showed significantly higher number of leaves, higher shoot length increase and higher root length increase compared to root un -pruned young seedlings and root pruned and un-pruned mature seedlings. Grafted mature seedlings with or without root pruning showed slow growth. Five months after grafting, grafted plants were transplanted in the field. Results showed that 100 % root pruned grafted plants produced by using 10 months old rootstock and young 1.5 months old root stock were survived 3 months after transplanting at Gannoruwa research field (Table 3). In farmers field at Wattegama, plant were transplanted, 2 months late due to drought condition prevailed in the area. Two weeks after transplanting, 100 % survival was observed in all treatments except T3 treatment. In Navalapitiya field, survival rate is high in root pruned plant. However, mature plant without root pruning also showed higher survival percentage. Survival percentage of root un-pruned grafted plants produced by grafting 1.5 months old rootstock were lowest compared to other treatments.

Table 2: Effect of root pruning and rootstock age on percentage grafting success and survival after grafting.

EFFECT OF ROOT PRUNIING AND RE-POTTING ON DURIAN 227 Treatments Percentage 12 weeks after grafting success of Percentag Shoot Root grafting e survival length length increment increment (cm) (cm) a b 1. 10 months old rootstock , without root 96 95.8 11.2 c 12.9 pruning 2. 10 month old rootstock root pruning after 76 b 89.8 12.5 bc 11.2 c grafting and repotting 3. 1.5 month rootstock, without root pruning 90 a 93.4 14.8 b 11.6 c 4 1.5 month old rootstock, root pruning 90 a 95.6 16.5 a 13.7 a after grafting and repotting CV% 1.9 1.4 1.7 2.1 LSD(0.05) ** ns ** ** Note: CV=Coefficient of variation; Mean in each column followed by the same letters are not significantly different at P = 0.05.

Root pruning has the potential for increasing the amount of absorbing roots. This would help to increase water absorption and a potential for increased survival and reduced transplanting shock (Watson and Sydnor, 1987). Results of present study showed that root pruning has positive effect to increase the growth of roots and shoot and survival after transplanting. Effect of root pruning is more prominent in grafting of young seedlings. Success rate of grafting is lower by grafting mature seedlings and root pruning. Therefore, grafting at young stage and root pruning at grafting can be recommended to increase survival rate after transplanting and increase root and shoot growth. Table 3: Effect of root pruning and rootstock age on survival rate after transplanting of Durian. Treatments Survival after transplanting Gannoruwa 3 Wattegam a 2 Navalapitiya month after TP weeks after 3month after TP TP 1.10 months old rootstock , without root a 80 100 60 pruning after grafting 2. 10 month old rootstock root pruning after 100 a 100 a a grafting and repotting 80 00 00 O 00 O

b 3. 1.5 month rootstock, without root pruning 40 after grafting 4. 1.5 month old rootstock, root pruning after 100 a 100 a a grafting and repotting 80 CV% 3.5 2.6 8.3

CONCLUSION

Root pruning after grafting of 1.5 months old durian seedlings and re-potting has shown higher grafting success, shoot and root growth and higher percentage survival after transplanting. Therefore, grafting of young seedlings and root pruning at grafting can be used to production of planting materials of Durian.

REFERENCES

Ghani, M.A. 1992. Effect of root pruning on the quality of Durian (Durio zibethinus

228 EDIRIMANNA et al. Murr.) planting material.Acta Horticulture. 322: 31-32. Gilman, E.F. 1992. Effect of root pruning prior to transplanting on establishment of southern Magnolia in the land scape.Journal of Arboriculture 18 (4). Masri, M., Azizah, H., Mohd. Raz, I. and A. S. Mamat. 1998. Root morphological characteristics in relation to growth of four tropical fruit seedlings J. Trop. Agric. and Food. Sci. 26 (1): 17-24. Watson, G.A. and T. Davis Sydnor 1987. The effect of root pruning on the root system of nursery trees. Journal of Arboriculture 13 (5). Wieble, J., Chacko, E. K. and Downton, W. J. S. 1992. Mangosteen (Garcinia mangostana L.):a potential crop for tropical northern Australia. Acta Horticulture. 321: 132-7.

Annals of Sri Lanka Department ofAgriculture 2016. 18: 229 - 232 Short Communication

DEVELOPMENT OF EMBRYO RESCUE TECHNIQUE FOR WIDE HYBRIDIZATION OF CAPSICUM SPP

H.M.P.S. KUMARI, H.M.S.R.K. HERATH, MENAKA JAYATHILAKA, E.P WIJEWARDHANA, IROSHANI, S. KAHADAWAARACHCHI

Horticultural Crops Research and Development Institute, Gannoruwa, Sri Lanka

INTRODUCTION

Capsicum peppers are native plants of the New World tropics. They belong to the family Solanaceae which also includes potato, tomato and tobacco (Agrawel et al, 1983). Five different specices, Capsicum annuum, C. frutescens, C. chinense, C. baccatum and C. pubescens, are regarded as domesticated peppers (Campos et al., 2006). Interspecific hybridization is essential for introduction of genes from wild and related species into commercial varieties for disease and pest resistance, nutritional quality, yield and adaptation to stresses (Husain et al., 1999, Ramirez et al., 1996). Several interspecific hybrids were obtained within C. annuum complex, such as introducing Tobacco Mosaic Virus (TMV) resistance from C. frutescens to C. annuum , resistance to PVY and TEV from C. chinense to C. annuum partial resistance to CMV from C. baccatum to C. annuum ) or multiple-flower character from C. chinense into C. annuum (Agrawel et al . 1983,1989). Successful crosses between complexes are much more uncommon due to expression of unilateral or bilateral incompatibilities (Campos et al., 2006).

However, diseases namely, (TMV), root rot, Tomato Spotted Wilt Virus (TSWV), etc. leads to a considerable declining in yield in Capsicum annuum varieties; including chilli, bell pepper, capsicum etc. To overcome this problem, wide hybridization could be used to transfer the responsible genes from one species to another, but there has been very little success due to incompatibilities. To bypass these post-fertilization barriers, embryo-rescue, ovule culture and manipulations with protoplasts have been successfully used. The embryo rescue technique have been used with MS (1962) modified medium (Murashige et al., 1962). It is observe that the stage of development of the wide hybrid embryos at the time of culture is utmost importance; and the growth is strongly influenced by the age (Hogenboom, 1973). Therefore the present study was carried out to develop a method to overcome post fertilization barriers using embryo rescue techniques in order to transfer the

230 KUMARI et al. important traits from C. frutescence to C. annuum. Age of the embryo and compositions of the media are the major concerned area for this study.

MATERIALS AND METHODS

The experiment was carried out from September 2015 to February 2016 at the tissue culture laboratory of Horticultural Crops Research and Development Institute (HORDI), Sri Lanka. Wide hybrids were prepared using Capsicum annuum and C. frutescence . Two recommended varieties, Hungarian Yellow Wax (HYW), Lanka Yellow Wax (LYW) and one inbred line (1782) of C. annuum and three accessions of C. frutescence, C-8, C-12, C-17 were used for the study. Plants were established in plant house and inter specific hybrids were made . C. annuum varieties were used as the female parent and the C. frutescence as the male parent. To culture immature embryos, MS media containing different hormone concentrations were used (Table 1)

Table 1: Media composition. MS -A MS -B MS -C MS -D NAA (mg/l) 0.1 0.1 0.1 0.1 GA 3 (mg/l) 0.2 0.3 0.4 0.5 BAP (mg/l) - 0.1 0.2 0.3 Casein hydrolysate (mg/l) 500 500 500 500

Collected mature and immature fruits were washed by using running tap water for 30 minutes. There after pods were exposed to laminar air flow and further sterilized using 10% sodium hypochlorite solution for 10 minutes and dipped in 70% ethanol for 3 to 5 minutes followed by rinsing three times with sterile distilled water. Cultures were placed in a culture room under a controlled temperature (25 ±2°C with 1800-2000 lux, light intensity, (33-37 pE/m 2/s) with 16 hours light/8 hr dark/ day).

Germination was recorded at 14 days after the culture establishment. Germinated plantlets (10-11cm height) were transferred to potting media for further growth. Healthy rooted plantlets were then transplanted to clay pots (10 cm diameter) containing a mixture of sterilized top soil 2: sand 1: coir dust 1 mixture.

EMBRYO RESCUE TECHNIQUE FOR WIDE HYBRIDIZATION OF 231 CAPSICUM

RESULTS AND DISCUSSION

HYW and 1782 successfully produced well developed pods with all the crosses made between selected C. frutescence. However in cross combinations with LYW, successful pod formation was observed only from the LYW X C-8 cross. LYW x C-12 and LYW x C-17 crosses did not produce completely developed pods and immature pod drop was observed at 5 days after pollination. For these incompatible combinations where pod development was observed only for 5 days, embryos were cultured on embryo rescue medium at 5 days after pollination only.

Premature embryo germination percentage in different media combinations were analyzed using SAS (Statistical analysis software) statistical package (version 9.1") to determine the significance of differences between treatments at 0.05% probability. MSA, MS-B and MS-C showed lower germination of immature embryo (less than 10 %) compare to the MS-D (18% -41%) for the embryos collected 10-15 days after pollination. Germination ability at different age of the embryo showed significant difference. MS-A, MS-B and MS-C media did not show any embryo germination ability for embryo collected 5-10 days after pollination. Significantly higher pre mature embryo germination percentage (18% -41%) for all tested ages and embryo rescue ability for 5 days old embryos (18%) were observed only with MS-D medium. Low concentrations of auxins have promoted normal growth, and gibberellic acid has caused embryo enlargement (Agrawal et al, 1989). Selected rescue medium from this study also containing low concentrations of growth regulators NAA, BAP and GA 3 as 0.1 mg/l 0.3 mg/l and 0.5 mg/l, respectively.

CONCLUSION

Immature wide hybridized embryos collected 5-15 days after pollination germinated well in the embryo rescue MS medium, supplemented with Casein hydrolysate 500 mg/l, NAA 0.01 mg/l,GA 3 0.5 mg/l,BAP 0.1 mg/l . Immature embryos at the age of 5 days after pollination from incompatible crosses could be used to produce completely developed plants using selected embryo rescue medium.

This developed embryo rescue technique can be used to overcome incompatible barriers in wide hybridization of C. annuum and C. frutescens.

232 KUMARI et al.

REFERENCES

Agrawal, S. and Chandra, N. 1983. Differentiation of multiple shoot buds and plantlets in cultured embryos of Capsicum annuum L. val'. mathania. Curt. Sci. 52:645-646. Agrawal, S., Chandra, N. and Kothari, S.L.. (1989) Plant regeneration in tissue culture of pepper (Capsicum annuum L. cv. mathania). Plant Cell Tiss. Org. Cult. 16:47-55. Campos, K.P., Pereira, T.N.S., Costa, F.R., Sudre, C.P., Monteiro, C.E.S. and Rodrigues, R. (2006) Interspecific hybridization among cultivated germplasm in Capsicum. In: The 17th. International Pepper Conference. Naples, Florida, p. 20-20. Hogenboom, N.G. 1973. A model for incongruity in intimate partner relationships.Euphytica 22 (2): 219-233. Husain, S., Jain, A. and Kothari, S.L. 1999. Phenylacetic acid improves bud elongation and in vitro plant regeneration efficiency in Capsicum annuum L. Plant Cell Rep. 19:64- 68. Ramirez-Malagon, R. and Ochoa-Alejo, N. (1996) An improved and reliable chili pepper (Capsicum annuum L.) plant regeneration method. Plant Cell Rep. 16:226-231 Rep. 15:536-540. Williams, E.G., I.M. Verry, and W.M. Williams. 1982. Use of embryo culture in interspecific hybridization. In: Plant Improvement and Somatic Cell Genetics. Ed. I.K. Vasil, W.R. Scowcroft, and K.J. Frey. Academic Press, New York. 119-128.

Annals of Sri Lanka Department of Agriculture 2016. 18: 233 - 240

Short Communication

SUBMERGENCE TOLERANT RICE LINE FOR FLOOD PRONE AREAS IN SRI LANKA

M.G.N. R UPASINGHE 1, W.L.G. S AMARASINGHE 2 AND K.M.S. D E SILVA 1

1 Rice Research Station, Bentota,Sri Lanka 2 Plant Genetic Resources Centre, Gannoruwa, Sri Lanka

INTRODUCTION

Rice is mainly grown as a wetland crop due to its semi-aquatic nature and ability to survive in water logged soils. (Mackill et al., 1996; Fukao and Serres, 2008; Pucciariello and Perata, 2013) but sensitive rice cultivars die within a week under complete submerged conditions (Pereta, 2007). Flash floods, a rapid surge of water that subsides after several days and lasts no longer than 10 days, are common phenomena in the some parts ofKalutara, Gampaha, Ratnapura, Colombo, Matara and Galle districts in the Wet Zon (Nawarathna et al., 2014). In Sri Lanka, 0.2 million ha were destroyed in Maha 2010/2011 season due to floods leading to a yield loss of one third of total production. In 2013, approximately 75,000 ha of paddy lands had been affected due to flooding prevailed throughout the Maha season (Samarasinghe et al., 2014).

It was a common practice in the past to cultivate traditional rice varieties like “Ma wee ” in flood prone areas as they can escape from the submerged condition. However, these varieties are poor yielders with a grain yield of 0.75 to 1.0 t/ha (Jayawardena, 1984) while they can be grown only in Maha season as they are photoperiod sensitive. Due to the poor yields and one season cultivation farmers were reluctant to cultivate “Ma wee” varieties over improved high yielding rice varieties. Finally the farmers suffered from regular yield losses when they grow submergence- intolerant improved high yielding rice varieties in flood prone areas. Therefore to enhance the land productivity, improve the livelihood of the farmers in flood prone areas and for the food security in the country, a high yielding and submergence tolerant verities are one of the most appropriate solutions.

Submergence tolerance is regulated by the sub 1 gene and it has been successfully introgressed in to mega varieties and they have proven their submergence tolerance ability in India and Bangladesh. The locally available Bg 96-741 (released as Bg 455 in 2014) is a promising rice line for submergence (Rupasinghe et al., 2014).The present study was carried out to identify the suitable submergence tolerant exotic mega varieties to enhance the land productivity in flood prone rice growing areas in Sri Lanka.

234 RUPASINGHE et al.

MATERIALS AND METHODS

A field experiment was carried out at Rice Research Station, Bentota during Maha 2014/2015 and Yala 2015 seasons. Six rice varieties; Swarna sub 1, Samba mashuri sub1, IR 64 sub1, IRRI 119 sub1 and Bw 364 were checked with the variety Bg455.The flood water depth was maintained at 0.5 minute each experiment unit. Pregerminated seeds were sown in to the 18 m 2 plots. The experiment was laid out in a randomized complete block design with three replicates. Initial plant count in a unit area was randomly taken. At 14 days after seeding, seedlings were submerged to0.5m depth for the period of 10 days. Soil and water pH and electrical conductivity were recorded during the submergence period. At the end of 10 days of complete submergence plots were drained and plants were given 14 days for recovery and the survived plant density was measured in each plot and survival percentage was calculated. The normality of the data was tested. According to the Anderson-Darlin method (Pr>A-sq>0.25) data set is normally distributed. Analysis of variance and mean separation was done using Duncan’s multiple range test (DMRT) according to the randomized block design at the 0.05 significant level using SAS package.

RESULTS AND DISCUSSION

pH and EC values of the soil and water during submerged period is in favourable condition for the crop growth as shown in Table 1. In the tested two seasons, Bg 455 recorded the significantly higher survival % over the others after submergence. In 2014/15 Maha season, when compared to the exotic submergence tolerance rice varieties, Bg 455 and Bw 364 recorded the significantly higher survival percentage. Only 30% of the plants of Bg 455 died during the submergence period. All the exotic varieties had less than 50% survival after drainage. IRRI 119 sub 1 variety recorded a significantly higher survival % than that of IR 64 sub 1, Swarna sub 1 and Samba Mashri sub 1. In 2015 Yala season, 70% of the plants of Bg 455 survived after submergence. All the other varieties recorded less than 50% plant recovery after submergence.

Tested two local varieties have shown a higher level of survival percentage after receding the floods while sub 1 introgressed exotic mega varieties, survival percentage is lower. Toojinda et al. (2003) has shown that the expression of the genes for submergence

235 SUBMERGENCE TOLERANT RICE LINE FOR FLOOD PRONE AREAS

tolerance is also environmentally dependent. The results of this study also confirmed that the genes for submergence tolerance of the tested varieties were not expressed in the tested local environment.

Table 1. pH and EC values in soil and water during the submerged period. 2014/15 Maha 2015 Yala

pH (1:5soil:water) EC(dS/m) pH (1:5soil:water) EC(dS/m) Soil 4.7 0.47 4 0.36 Water 7.1 0.1 6.8 0.72

Table2. Survival percentage of the tested rice varieties after recovery. 2014/15 Maha Mean survival % 2015 Yala Mean survival % Treatments

Bw 364 65a 40b

Bg 455 70a 70a

IRRI 119 sub 1 33b 17c

IR 64 sub 1 18c 40b

Swarna sub 1 22bc 18c

Samba mashuri sub 1 16c 17c

CV % 19.8 29 Within a column, the means followed by the same letter are not significantly different by the Duncan’s Multiple Range Test (p=0.05)

CONCLUSION

The locally developed Bg 455 performed well in submerged environment than the introduced submergence exotic tolerant varieties. Therefore, Bg 455 can be successfully introduced to the flood prone areas and water logged areas in the country.

REFFERENCES

Fukao, T. and Serres, J.B. 2008. Ethylene-A key regulator of submergence responses in rice. Plant Science 175: 43-51.

236 RUPASINGHE et al.

Ismail, A.M., Mackill, D.J., Jackson, M., Ford-Lloyed, B and Parry, M. 2013. Response to flooding: submergence tolerance in rice. Plant genetic resources and climate change-a 21st century perspective. Wallingford, UK: CAB International. Pp 251-269. Mackill, D.J., Coffman, W.R. and Garrity, D.P. 1996. Rainfed lowland rice improvement. 1st Edition. International Rice Research Institute, Manila, Phillipines. 111-125. Perata, P. and Voesenek, L.A.C.J. 2007. Submergence tolerance in rice requires Sub1A, an ethylene-response-factor-like gene. Trends in Plant Science. 12: 43 - 46 Pucciariello, C. and Perata, P. 2013. Quiescence in rice submergence tolerance: an evolutionary hypothesis. Trends in Plant Science 18:377-381. Septiningsih, E.M., Pamplona, A.M., Sanchez, D.L., Neeraja, C.N., Vergara, G.V., Heuer, S., Ismail, A.M and Mackill, D.J. 2009. Development of submergence tolerant rice cultivars: the Sub1 locus and beyond. Annals of Botany. 103: 151-160. Rupasinghe, M.G.N., Samarasinghe. W.L.G. and De Silva, K.M.S. 2014.A promising Rice line Bg 96-741 for submergence prone areas.Annals of the Sri Lanka Department of Agriculture, 16:367. Samarasinghe, W.L.G., Priyandika, M.A.H., Sartaj, A.B., Gunadasa, J.G.D., Rathnayake, K., Kekulandara, D.S., Udawela, K.S. and Alwis, L.M.H.R. 2014. Improvement of Bg 360 for submergence tolerance by morphologically and molecular marker assisted back cross breeding.Annals of Sri Lanka Department of Agriculture 2014. 16: 1-9 Toojinda, T., Siangliw, M., Tragoonrung, S. and Vanavichit, A. 2003. Molecular genetics of submergence tolerance in rice: QTL analysis of key traits. Annals of Botany 91: 243-253.

Annals of Sri Lanka Department of Agriculture 2016. 18: 237 - 240

Short Communication

EFFECT OF MINIMUM TEMPERATURE FLUCTUATION DURING DORMANCY PERIOD ON TOTAL HARVESTABLE YIELD OF PEAR (PYRUS PYRIFOLIA) IN UP COUNTRY INTERMEDIATE ZONE OF SRI LANKA

Y.L.B. PAVITHRANI \ C.J. KARUNARATHNE 1 AND K.P. SOMACHANDRA 2

1 Agriculture Research Station, Rahangala, Sri Lanka. 2 Regional Agriculture Research and Development Centre, Bandarawela, Sri Lanka

INTRODUCTION

Pears have been introduced to Sri Lanka from the West Indies by the Portuguese about five centuries ago. Cultivars that belong to Pyruspyrifolia are known as sand pear due to the presence of stone cells in the flesh. “Rahangala Pear” is a variety recommended by the Department of Agriculture belongs to that group. In temperate climates sub-optimal temperatures restrict or terminate growth of plants. As a consequence, temperate plants have evolved mechanisms to survive low temperature stress during winter (Horvath et al., 2003). This annual rhythm has periods of active meristem growth separated by periods of dormancy or ‘rest’ which avoids low temperature injury. Dormancy minimizes low temperature injury to flowers by delaying bud break and anthesis. Perennial crops have to satisfy their chilling requirements to initiate bud break, shoot meristem elongation, growth and anthesis. Chilling requirements are species and cultivar specific and are genetically determined (Samish, 1954). Recent changes in climate in the Up Country Intermediate Zone (UCIZ) have directly affected the pear production. Therefore the objective of this study was to identify yield fluctuation pattern of Pear with changing minimum temperatures in UCIZ. This information could be used for predicting Pear yield and to find alternative flower induction methods and environment manipulations to continue stable fruiting of pear.

MATERIALS AND METHODS

This study was based on the available weather and Pear yield data collected at the Agriculture Research Station, Rahangala from 2010 to 2015. There are 4 blocks of “Rahangala Pear” variety with the size of one acre (250 plants/Ac) and their yields were separately recorded from year 2010 to 2015. Daily weather data was collected from weather station at Rahangala Research Station. Monthly average minimum temperature (AMT) was calculated by using daily minimum temperature data. AMT of November to March was used for evaluations because they are the coldest months of the year. To fulfil the chilling requirement of

238 PAVITHRANI et al.

pear plant, temperature during dormant period should be below 15 0C. Within period of November to March, the minimum temperature at Rahangala has decreased to below 15 0C. Yield data were analyzed using Analysis of Variance (ANOVA) procedure using Statistical Analyzing System (SAS system for Windows 9.0) computer package. Mean Separation was done by Duncan Multiple Range Test (DMRT) at p<0.05.

RESULTS AND DISCUSSION

Variation in pear yield along with different minimum temperature fluctuations in related chilling periods are given in Table 1. Mean yield of pear was significantly influenced by AMT value of the respective chilling period. Decrease of AMT up to 13.5 0C has increased the mean yield up to 4,093.8 kg/ha. In 2011/12, dormancy period shows gradual reduction of AMT while reaching its minimum in March (Figure 1). It has sufficiently fulfilled the chilling requirement to produce high yield.

Table 1. Mean pear yiel d under different minimum temperatures prevailed from 2010 to 2015. AMT in dormancy period with Standard Error Mean yield (kg/ha) 2009/10 (14.1 0C± SE 0.63) 1,985.6 c 2010/11 (14.7 0C± SE 0.37) 1,285.8 d 2011/12 (13.5 0C± SE 0.78) 4,093.8 a 2012/13 (15 0C± SE 0.35) 2,736.1 b 0 2013/14 (13.7 C± SE 0.75) 2,886.1 b 2014/15 (14.7 0C± SE 0.56) 1,745 c CV% 17.90 R2 0.8825 Note: means denoted by same letter is not significantly different from each other, at p = 0.05

However, in 2012/13 and 2013/14, dormancy period has end up in the month of February while shortening the chilling period. AMT in February has sudden reduction which is positively effect on pear yield in 2013. In 2009/10, AMT in dormancy period shows great reduction but it did not move below 12 0C. It has not satisfied the full chilling requirement to produce good yield.

EFFECT OF MINIMUM TEMPERATURE FLUCTUATION ON YIELD OF 239 PEAR

Figure 1: Minimum temperature changes during dormancy period from November to March During 2014/15 cold season, AMT in January to March was close to 14 0C, which is comparatively high value that had cause a great reduction in yield (1,745kg/ha). Average potential yield of pear is 2,500-3,000 kg/ha in Rahangala area but it can be maximized up 4,093 kg/ha level with the favourable climatic conditions (Average minimum temperature in chilling period). Data has shown that increase of AMT reduces the total yield of pear (Figure 2). Increase of AMT means reduction of chill hours that is necessary for reproductive development and crop yield of pear. Reproductive development in perennial temperate crops occurs prior to and after winter dormancy and involves an extended sequence of morphological, physiological, metabolic and molecular changes. These events include floral development, dormancy itself, the satisfaction of chilling and bud break. All these are linked to the process that induces vegetative meristems to develop into fruits. Most deciduous perennial crops initiate next year’s floral buds in late summer or early autumn, coinciding with final stages of that year’s fruit development (Atkinson et al, 2013).

After low temperature exposure (‘chilling’), followed by satisfaction of the heat sum, to come out of ecto dormancy, bud break is induced and anthesis follows. During these protracted phases the climate is the key to determining perennial crop production. Climate is the dominant factor in many temperate fruit yield models, with variation in temperature, around flowering, showing high statistical significance in explaining year- to-year differences in yield (Atkinson et al., 2013) which confirms the results of the present study.

240 PAVITHRANI et al.

Figure 2: Relationship between minimum temperature and pear yield.

CONCLUSION

Pear yield is highly correlated with minimum temperature at the dormancy period (November to March).Scientists predict that global temperature will gradually increase in near future and it will adversely affect to the Production of Rahangala Pear in UCIZ. When temperature increases, minimum temperature in dormancy period already increases and Pear plant unable to fulfil its chilling requirement to continue reproductive development. Therefore we have to focus on alternative methods to facilitate chilling requirement. Further it is important to identify and introduce new varieties with minimum chilling requirements to overcome these anticipated climatic barriers in the future.

REFERENCES

Atkinson, C.J., Brennan, R.M., Jones, H.G., 2013. Declining chilling and its impact on temperate perennial crops. Journal of Environmental and Experimental Botany 91, 48-62. Horvath, D.P., Anderson, J.V., Chao, W.S., Foley, M.E., 2003. Knowing when to grow: signals regulating bud dormancy. Trends in Plant Science 8, 534-540. Samish, R.M., 1954. Dormancy in woody plants. Annual Review of Plant Physiology 5, 183-204.

Annals of Sri Lanka Department of Agriculture 2016. 18: 241 - 240 Short Communication

AN ACTION THRESHOLD AND A FUNGICIDE SPRAYING SCHEDULE FOR RUST AND ANGULAR LEAF SPOT IN BEAN

E.A.E.S.S. JAYASEKARA, K.P. SOMACHANDRA, W.M.S. GUNASEKARA, K.K.N.N. GUNAWARDHANA AND G A R. SOMASIRI

Regional Agriculture Research and Development Centre, Bandarawela, Sri Lanka

INTRODUCTION

Bean (Phaseolus vulgaris), a popular vegetable worldwide and an excellent source of protein, is cultivated around 7,592 ha in Sri Lanka producing 46,985 mt annually (AgStat, 2013). Up Country intermediate zone, with its average temperature of 18.5-28 0C provides an ideal environment for many fungal pathogens. Angular leaf spot (ALS) (Isariopsis griseola) reduces 7.9% yield for every 10% increment of its severity (Pamela et al, 2014) while rust (Uromyces appendiculatus) can cause 8-100% yield loss (Ariyarathne and Nuwan, 2001) in bean production. Both diseases can be effectively controlled by using resistant cultivars and fungicides. Since no resistant ben cultivar available, and climate is conducive for these diseases in Sri Lanka, fungicides is the one stop remedy. Therefore, identification of action threshold and a fungicide spraying schedule based on yield loss due to these diseases is important.

MATERIALS AND METHODS

Experiments were at Regional Agriculture Research and Development Centre (RARDC), Bandarawela. Experimental plots (6 m 2) were constructed maintaining 1 m spacing between plots to reduce spray drift. The bean variety, Keppetipola nil was used in all experiments. Yield loss assessment experiment (Yala 2014, Maha 2014/2015) included intensive fungicide application started before the onset of diseases (Chlorothalonil 500 g/l SC in 7 days followed by Tebuconazole 250 g/l EW in 21 days up to flowering, then only Chlorothalonil 500 g/l SC up to 7 days before 1 st pick) and water spray (no fungicides). Fungicide spraying schedules evaluated (Maha 2012/ 2013) were, Chlorothalonil 500 g/l SC in 7 days (T1), Tebuconazole 250 g/l EW in 21 days (T2), Hexaconazole 50 g/l EC in 21 days (T3), Tebuconazole 250 g/l EW followed by Chlorothalonil 500 g/l SC in 21 days and 7 days alternatively (T4), Hexaconazole 50 g/l EC followed by Chlorothalonil 500 g/l SC in 21 days and 7 days alternatively (T5), Tebuconazole 250 g/l EW (initial spray only) followed by Chlorothalonil 500 g/l SC in 7 days (T6), Pyraclostrobin 5% + Metiram 55% WP in 14 days (T7) and water spray (T8). Application was started at 10% disease severity and ceased 7 days before 1 st pick. Experiment on determination of action threshold in yala 2014, fungicide spraying was

242 JAYASEKARA et al.

started with the appearance of disease in two lowermost leaves (T1), in four lowermost leaves (T2), in six lowermost leaves (T3), in eight lowermost leaves (T4), in ten lowermost leaves (T5), with the onset of disease (T6) and untreated control (Water spray) (T7). Second fungicide spraying was done when disease progressed to next two leaves, keeping seven days interval between two applications and application continued up to flowering. All experiments were arranged in randomized complete block design. Eight replicates were used for yield assessment while three replicates were used for the other two experiments, respectively. Disease severities were recorded in weekly intervals using diagrammatic scales (Godoy et al., 1997, 2006) with the onset of rust or ALS symptoms, and converted in to measurements of Area Under Disease Progress Curve (AUDPC) (Jesus Junior et al., 2001). Non parametric CATMOD procedure was used for AUDPC values in SAS (Anderson-Darling test statistics p< 0.05). The yield loss percentage was determined using the method described by Pamela et al. (2014).

RESULTS AND DISCUSSION

AUDPC values for rust and ALS in both seasons were low and yield was high in fungicides treated plots with average yield loss of 23.4%. Severity of rust was high in yala 2014 than maha 2014/2015 (Table 1). Low night and high day time temperature coupled with wind during yala may have aggravated the rust because it spreads by windborne inoculums. Photosynthetic capacity of leaves decreased with increase of both diseases. Results revealed that yield was lower in yala than in maha. High temperature disrupts fertilization and ovule development and floral abscission leading to reduced seed set and low and deformed pods (Wasonga, 2010).

All fungicides spraying schedules significantly reduced both diseases compared to untreated control, and yields were higher in all treatments except T1 and T8 (Table 2). Contact fungicides combined with systemic helps to minimize the selection of fungicide resistant races to the pathogen (Melendez et. al., 1986). Although, T1, T2, T3 and T6 effectively suppressed both diseases compared to T4, T5 and T7, there was no significant difference among treatments for yield (Table 3). It may be due to no disease suppression after flower initiation and maximum applications. Table 1: AUDPC values (Rust, ALS) and percentage yield loss in yala 2014 and maha 2014/2015. 2014 Yala 2014/2015 Maha Treatment AUDPC- AUDPC - Yield Yield AUDPC- AUDPC - Yield Yield bean ALS (t/ha) loss bean ALS (t/ha) loss rust (%) rust (%) T 1 112.55 b 84.79 b 6.84 a - 38.55 b 77.35 b 21.06 a - T 2 360.87 a 296.55 a 5.29 b 22.66 95.98 a 177.17 a 16.03 b 23.88 CV% - - 16.70 - - - 12.47 - Note: Disease severities of rust and ALS were assessed by Godoy et al. (1997) method.

ACTION THRESHOLD AND FUNGICIDE SPRAYING SCHEDULE FOR RUST 243 Table 2: AUDPC values for rust and ALS and yield (t/ha) in maha 2012/2013. Treatment AUDPC -bean AUDPC - ALS Yield (t/ha) Number of rust applications T1 3895.85 b c 1206.4 b 11.29 c d 05 T2 2701.65 d 623.85 c d 12.19 b c 02 T3 2977.1 d c 600.65 d 12.85 a b c 02 T4 2661.4 d 573.3 d 14.25 a b 02/03 T5 2780.4 d 715.95 c 14.75 a 02/03 T6 2836.05 d 718.3 c 11.58 c 04 T7 1951.6 e 424.25 e 14.70 a 03 T8 4343.15 a 1514.7 a 9.27 d - CV% - - 9.54 Note: Disease severities of rust and ALS were assessed by Godoy et. al., 2006 method

Table 3: AUDPC for rust and ALS, yield (t/ha) and time of fungicides application in yala 2014. AUDPC - nd a Treatment AUDPC- rust Yield (t/ha) DAS to DAS to 2 pp ALS 1st app T1 98.37 a 71.95 a 7.20 a b 33 44 T2 82.25 a 45.21 a 7.17 a b 41 48 T3 124.83 a 116.80 a 7.99 a 43 50 T4 174.58 b 238.48 b 7.30 a b 50 - T5 212.46 b 164.58 b 7.39 a b 53 - T6 132.88 a 101.48 a 7.81 a 33 48 T7 224.24 b 243.67 b 5.55 b - - CV% - - 18.32 - - DAS=Days after seed establishment; app= application Note: Disease severities of rust and ALS were assessed by Godoy et. al., 1997 method

CONCLUSION

Average yield loss associated with bean rust and ALS in Keppetipola nil under field condition was nearly 23.44%. Two applications of Tebuconazole / Hexaconazole alternatively with three applications of Chlorothalonil were effective for suppression of both diseases when disease progression was observed.

REFERENCES

Agstat.2013. Pocket book of Agricultural statistics. Department of Agriculture. Sri Lanka.Ariyarathne, H.M. and Nuwan E.A.P. 2001. A simple method to screen bean seedlings against bean rust. Annals of the Sri Lanka Department of Agriculture. 3: 1-7. Godoy, C.V., Carneiro, S.M.T.P., Iamauti, M.T., Pria, M.D., Amorimi, L. Berger, R.D. & Filho A.B. 1997. Diagrammatic scales for bean diseases: development and validation. Journal of Plant Diseases and Protection. 104 (4), 336-345. Godoy, C.V., Koga, L.J. and Canteri M.G. 2006. Diagrammatic scale for assessment of soyabean rust severity. Fitopatologia Brasileira. 31(1). 63-68. Jesus Junior, W.C., Vale, F.X.R., Martinez, C.A., Coelho, R.R., Hau B., Zambolim, L. Costa, L.C. and Filho, A.B. 2001. Effects of angular leaf spot and rust on yield

244 JAYASEKARA et al. loss of Phaseolus vulgaris. Epidemiology. 91(11). 1045-1053. Melendez, P.L., Rodriguez, R. and Wessel-Beaver, .L. 1986. Bean rust control under field conditions with systemic and contact fungicides. Journal of Agriculture of University of Puerto Rico. 70(1).45-55. Pamela, P., Mawejje, D. and Ugen, M. 2014. Severity of angular leaf spot and rust diseases on common beans in Central Uganda. Uganda Journal of Agricultural Sciences. 15(I):63-72. Wasonga, C.J. 2010. Combining common bean rust resistance and heat tolerance in snap beans (Phaseolus vulgaris L.) for Eastern Africa. Unpublished Ph.D. Thesis. Cornell University. New York. Pp 88.

Annals of Sri Lanka Department of Agriculture 2016. 18: 245 - 249 Short Communication

RELATIVE WEED COMPETITIVENESS ABILITY OF SOME SELECTED BW RICE VARIETIES IN LOW COUNTRY WET ZONE, SRI LANKA

W.R.K.D.W.K.V. WICKRAMASINGHE, D.C.M. PARANAGAMA, M.K.

KURULUGAMA AND S.D. UMANGE

Regional Rice Research and Development Centre, Bombuwela, Sri Lanka

INTRODUCTION Weeds cause serious yield reductions in rice production worldwide. Losses caused by weeds vary from country to country, region to region depending on the predominant weed flora and the control methods practiced by farmers. Weed control in the past has been carried out through a combination of weeding and water management. However, as a result of labor shortage, herbicide based weed management is becoming the most popular weed control method in rice cultivation in Sri Lanka. Reduction of dependence of farmers on herbicides is desirable to reduce herbicide costs, to minimize environmental pollution, and to delay the evolution of herbicide-resistance weeds (Mahajan et al., 2013). Crop competitiveness against weeds is composed of tolerance to weed infestation which is the ability of crop to maintain high yield under weedy conditions (Fischer et al., 1997). The first objective of this study was to evaluate the weed competitiveness and yield potential of some popular Bw rice varieties to identify superior genotypes that could potentially be used in integrated weed management.

MATERIALS AND METHODOLOGY

This study was carried out at Regional Rice Research and Development Centre, Bombuwela during ‘yala ’ 2015 and ‘maha ’ 2015/16. The experiment was established in a split plot design with three replicates. The main plots included three levels of weed infestation (weed free, partially weed free and un-weeded) and sub plots (5 m x 3 m) included five recommended 3.5 month Bw rice varieties (Bw 372, Bw 367, Bw 363, Bw 361 and Bw 267-3). In the weed free plots, asiumsulfuron (60 g a.i / ha) was applied at 10 days after sowing (DAS), followed by hand weeding to remove all weeds during the season. In the case of plots with partially weed condition, plots were hand weeded only once at the 4 weeks after sowing (WAS) and kept un-weeded throughout the season. Any weed control measures was not practiced in un-weeded plots. Maintenance of plots with

246 WICKRAMASINGHE et al. natural weed growth is helpful to understand the occurrence of weed flora and calculation of yield loss % under un-weeded condition is important to understand the importance of weed control in the Low Country Wet Zone of Sri Lanka.

Weeds were counted at 4 WAS and 6 WAS and categorized to sedges, broad leaf and grasses. Weeds collected at 6 WAS were washed with tap water, sun dried before oven dried at 70 oC until reaches a constant weight. The relative yield loss (YL) and the weed competitive index (CI) of the crop was calculated using the Eq1 and Eq2 as depicted below. Data were analyzed by using portable SAS program. Eq1 YL (%) = 1- (Y cw / Y fw) where, Y cw and Y fw are crop yield in competition with weeds and weed free conditions, respectively.

CI I Y infest fY mean ] Eq2 [W infest fW mean ]

Where, Yin fest is yield of variety ( i ) in terms of weed infested. Y means is the average yield of all varieties in the presence of weed. W,- is weed biomass variety of ( i ) Wmean is the average weed biomass of all varieties.

RESULTS AND DISCUSSIONS

Weed flora and weed density: The weeds presented in the field were Isachne globosa (Batadalla), Leptochola chinensis (Ashwa waligaya), Echinochola crus-galli (Maruk), Ludwiga octoralris (Bim uru) Monochoria vaginalis (Diya habarala), Lymnocharis flava (Diya gova), Commelina bengalensis (Girapala), Cypress rotundus (Kalanduru), Cyperus difformis (Bola thunessa), Fimbristyllis spp (Kudamatta) and Schoenoplectus grossus (Thunhiri). Weedy plots showed a high density of Ischane globosa with low counts of broad leaf and sedges compared to partially weeded plots. The density and the biomass of grasses were higher than those of broad leaf and sedges in all the rice varieties tested in Yala 2015 season (Figure 1). However, the number of grasses/m 2 and weed biomass were significantly (P<0.05) low in Bw 372 and Bw 361 rice varieties compared to other Bw varieties tested. According to Maha 2015/16 there were very low weed density in partially and unweeded plots , because of that, there were no significant yield differences among three different weed conditions, so herein after only discussed yala 2016 results.

_ 120 100 T T 7T J £• ■ Broad T380 60 40 20 0 Bw 267-3 Bw 363 Bw 372 Bw 361 Bw 367 a> leaves Rice variety ■ Sedges RELATIVE WEED COMPETITIVENESS ABILITY OF BW RICE■ GrassesVARIETIES 247

Figure 1:Weed biomass (g /m 2) in response to different varieties at 6 WAS under partially weeded conditions in yala 2015.

Relative Yield losses and Weed Competitive Index: Analysis of variance and mean separation showed that there were significant differences of yield (t/ha) between two different weed pressures (Table 1). The yield and total weed density varied significantly according to the weeding condition and rice variety. However, there was no significant interaction between weeding condition and rice variety.

Tablel: Average total weed density and rice yield of partially weeded and un-weeded conditions. Weeding condition Total number of weed /m 2 Average yield (t/ha) Un -weeded plots 6,148 a 1.33 b Partially weeded plot 2,337 b 2.02 a Values followed by different letters within the column were significantly different at P<0.05

As expected, average grain yield of all genotypes in weedy and partially weedy conditions decreased significantly (P<0.0J) compared to the average yield (3.20 t/ha) in weed free condition. Table 2 shows the average yield of rice varieties tested under three weeding conditions.

The percentage of relative yield loss varied from 42.8 to 75.2% and from 29.4 to 49.4% under un-weeded and partially weeded conditions, respectively. Given the fact that the farmers always apply weed control measures at least once it could be generally expected a partially weeded condition in the field. According to the results of the present study, the yield loss in the Low Country Wet Zone could be expected to be varied from 30 to 50%. In addition, the results of the preset study showed that Bw 372 has recorded

248 WICKRAMASINGHE et al.

the lowest yield loss of 15.2% among the Bw rice varieties tested under partially weeded conditions. Table2: Average yield (t/ha) of the selected rice varieties under three weeding conditions

Rice Variety Weed free Partially Weeded Un -weeded Condition Condition Condition Bw 267 -3 3.14 a 2.25 ab 1.68 a Bw 361 3.52 a 2.37 a 1.45 a Bw 363 3.19 a 1.72 c 0.79 b Bw 367 3.36 a 1.55 c 1.13 ab a Bw 372 2.82 a 2.75 1.60 a CV 23.00 12.76 22.46 Values followed by different letters within the column were significantly different at P<0.05

The highest weed competitive index was recorded in BW 372 (1.99) followed by Bw 367 (1.45). All the other rice varieties tested showed a weed competitive index less than 1.00. Accordingly, Bw 372 and Bw 361 could be considered as the highly weed competitive rice varieties among the Bw varieties tested (Figure 2).

Bw 267-3 Bw 363 Bw 372 Bw 361 Bw 367 Rice variety

Figure 2: Weed competitive index of selected rice varieties

CONCLUSIONS

The two rice varieties, Bw 372 and Bw 361 appeared as the most competitive varieties against weeds. The high yielding rice variety Bw 367 showed very low weed competitiveness. Since, the competitive ability of rice genotypes is a complex trait decided by many factors detail investigations are needed to study the weed competitiveness shown by the BW varieties tested.

RELATIVE WEED COMPETITIVENESS ABILITY OF BW RICE VARIETIES 249 REFERENCESS

Mahajan G., B.S. Chauhan and M.S. Gill. 2013. Dry-seeded rice culture in Punjab State of India: lessons learned from farmers..Field Crops Research, vol. 144, pp. 89-99. Mahajan, G., M.S. Ramesha and B.S. Chauhan. 2014. Response of rice genotypes to weed competetion in dry direct seeded rice in India. The scientific world Journal, Accessed on 5 th May 2016, http://dx.doi.org/10.U55/2014/641589 .

Annals of Sri Lanka Department ofAgriculture 2016. 18: 250 - 253

Short Communication

IMPACT OF USAGE OF AGRO-CHEMICALS ON SOIL BIO DIVERSITY IN VEGETABLE FIELDS AT MANDARAM NUWARA IN NUWARA ELIYA DISTRICT

R.G.S. IROSHANI 1 AND K. MOHOTTI 2

1 Horticultural Crops Research and Development Institute, Gannoruwa, Sri Lanka 2 Tea Research Institute, Thalawakele, Sri Lanka

INTRODUCTION

In new century, most of the developing countries are facing two major problems such as, lack of sufficient food and increasing environmental degrades. To fulfill the increasing demand for food, different innovative technologies have been introduced from time to time and agricultural practices have gone through various stages of transition. Newly improved crop varieties grown on commercial scale are often treated with heavy dressings of agro chemicals, chemical and other mineral fertilizers to enhance growth towards high productivity. Reduction of biodiversity is identified as one of the direct result of these practices.According to the cropping intensity, Nuwara Eliya is recorded to have high intensive cultivation. To maximize profit, farmers practice heavy dressings of agro chemicals, chemical and other chemical fertilizers. But, they practice chemicals with higher frequency and higher amount than recommended. Mandaram Nuwara is a remote village in Nuwara Eliya district which is recorded as highly polluted area with reference to records of UNDP.Therefore, the present study was initiated to study the status of soil biodiversity components under heavy agro chemical usage, and to make a comparison of high intensive agriculture systems and organic farming systems.

MATERIALS AND METHODS

This study was carried out at Mandaram Nuwara in Nuwara Eliya District which comes under WU 2a agro-ecological region. Twenty four different sites, representing different farming systems as forest, organic farms (in conversion), home gardens, vegetable fields were used in the study (Table 1). Twenty four random soil samples were taken from 0-30cm depth of soil and 1 kg of wet soil samples were used to analysis microbial activity, earthworm population and micro arthropods in the soil. The following analyses were made using the soil samples drawn from experimental sites.

CO 2 evolution rate in soil was used to determinethe microbial activity by using in-vivo method (Anderson, 1982). Soil micro arthropods were extracted in water using a simple modification of Berlese apparatus to determine the micro-arthropod density. Earthworm

EFFECTS OF AGRO-CHEMICALS ON SOIL BIO DIVERSITY 251 populations in 1000g of soil in 1/4m 2 in each site were determined at depth of 0-15 cm. Data analysis was done by using SAS statistical package.

Tablet : Description of selected sites for the study.

Treatments Farming system Number of sites T1 Forest 6 T2 Organic farms (in conversion) 6 T3 Home garden 6 T4 Vegetable fields (HIAS) 6

RESULTS AND DISCUSSION

Soil microbial activity was significantly differed among soil types (P<0.05)

(Table 2). Amount of CO 2 evolution represents the number of living organisms including micro organisms and plant roots. According to the analyzed data, the highest microbial activity could be seen in natural forest indicating highest population among tested soil samples. There was a clear depletion pattern from forests to vegetable fields. In home gardens, highest values of CO 2 evolution rate were recorded with the comparison of farming systems. Home gardens are not affected with agricultural practices such as tillage, weeding, fertilizing etc. Chemical fertilizers and pesticides are not used in this farming system and therefore, microbial community is not severely affected with pesticides and chemical fertilizers. Tested soil samples in vegetable fields showed much lower CO 2 evolution rates with a little variation within this farming system. According to Mark (2002), biocides and chemicals affect microbial populations at least temporarily. However, the microbial activity showed significant depletion in conventionally managed soils compared to that in the forest (P<0.05).

Table 1: Soil microbial activity in different farming systems. Treatment CO 2 evolution rate (g/day) T1 11.41 a T2 4.67 c T3 6.05 b T4 2.2 d CV 16.78

252 IROSHANI AND MOHOTTI

Earthworm population differed among soil types (Figure 1). The highest earthworm population was present in natural forest, while the lowest was recorded in vegetable fields. Earthworm population decreased with cultivation due to the reduction in organic matter, with tillage which causes mechanical injuries and upon pesticide application which is toxic in nature.

20 in E = 15 .c o 10 t! 5 w) i rc O 0) 0 O M - ® T1 T2 T3 T4 O '-I o Farming systems

Figure 1: population (Number/1,000g soil) of earthworms in soil.

Among the different farming systems used in this study natural forest system showed the highest diversity with respect to micro arthropods communities. Lowest diversity could be identified in vegetable fields which are conventionally managed farming systems. However, home gardens and organic farms showed higher diversity of micro arthropod communities. Micro arthropods are the most affected part by chemicals due to their soft bodies. All micro arthropod groups showed significant differences among different farming systems (Figure 2). Myriapods as compared to insects, collombolans and mites were present in low densities in all the organically managed soils. Even in the tropical forest soils, densities of myriopodswere lesser compared to insects, collembolan and mites.

■ Insects ■ Collombolan s ■ Mites ■ Miriopedes

Figure 1: Density (Number/100g soil) of micro arthropods in soil

EFFECTS OF AGRO-CHEMICALS ON SOIL BIO DIVERSITY 253 CONCLUSION

In respect of microbial activity, soil micro arthropods and earthworm population, the highest soil biodiversity showed in natural forest system and the lowest in intensive vegetable cultivation systems. Soil biodiversity in organic cultivations and home gardens was higher than conventional farming systems. Intensive cultural operations and indiscriminate usage of agrochemicals are the causes to decrease microbial population and earthworm population which are highly sensitive for operation and chemicals with their soft bodies. Therefore, conserved soil biodiversity was seen in organic cultivations and home gardens than in high intensive agricultural systems.

REFERENCES

Anderson, J.P. 1982. Method of Soil Analysis. Part 2.Chemical and Microbial Properties. Agronomy Monograph no.9, Second Edition. 831-871 Hance, R.J. 1980. Interactions between Herbicides and Soil. European Wed Science Society: London, 255-299 Coyne, M.S. 1999. Soil Microbiology an Exploratory Approach, Delmar Publishers, New York, USA.

Annals of Sri Lanka Department of Agriculture 2016. 18: 254 - 258

Short Communication

EVALUATION OF FRUITING ABILITY AND FRUIT QUALITY THROUGH DIFFERENT TRAINING SYSTEMS OF APPLE

E.K.E.C. NAYANA, D.M.R. DASSANAYAKE, Y.L.B. PAVITHTHRANI AND M.A.L.N. MALLAWAARACHCHI

Regional Agriculture Research and Development Centre, Bandarawela, Sri Lanka

INTRODUCTION

Apple is a popular fruit crop among Sri Lankans which is supplied mainly through importation at a huge expense of foreign exchange. In year 2103 alone, rupees 1.8 billions were spent for importation (AgStat, 2013). Imported fruits with harmful chemicals that are being used for long shelf life is the major issue of faced by Sri Lankan in consuming this fruit. There are some Apple ( Malus domestica ) trees cultivated in a few home gardens in Up Country Intermediate Zone (UPIC) and Up Country Wet Zone (UCWZ) in Sri Lanka. Climatic conditions in both these agro-climatic zones are conducive for flowering and fruit bearing of apple. However, the pruning systems used is not appropriate to obtain quality fruits and an economical yield. Most commonly used tree pruning types are Centre leader and Centre open approach. Hence, new training types and agronomic practices are required to increase the productivity of Apple trees in Sri Lanka. Therefore, this study was carried out to evaluate fruiting ability in UCIZ through different training systems of Apple.

MATERIAL AND METHODS

The experiment was conducted at the Regional Agriculture Research and Development Centre (RARDC), Bandarawela from August 2012 to June 2013. The experiment was carried out with six years old Apple trees with 4.5X 4m spacing. Selected trees for which treatments were imposed has been subject to Centre open pruning. The crop management practices were done according to the DOA recommendations. In the experiment, treatments were taken as Centre open pruning + branches angle 45 0 - 60 0 from vertical (T1), Centre open pruning + excess flowers thinning (T2), Centre open pruning + branches angle 45 0 - 60 0 from vertical + excess flowers thinning (T3) and Centre open pruning (T4) as a control were laid out in a Randomized Completely Block Design (RCBD) with four replicates. Data recording was started from the beginning of flower blooming and continued up to fruit maturity. Aforesaid tree training methods were started at the vegetative stage of the tree.

Fruit quality parameters such as fruit weight, firmness, pH and Brix (TSS) were also measured in the horticulture laboratory. The experiment was arranged according to

FRUITING AND FRUIT QUALITY CHANGE THROUGH TRAINING OF APPLE 255 a Completely Randomized Design (CRD) with four replicates. Data were subjected to ANOVA procedure to obtain treatment means using SAS 9.1.3 statistical software. The statistical differences among treatment means were tested by DUNCAN procedure (P=0.05) test. Sensory evaluation was done by panelist’s evaluation of Apple fruits. The parameters of taste, colour and mouth feel (crispiness) were evaluated. Ten numbers of panelists were involved in the sensory evaluation. Data were analyzed using SPSS statistical software.

RESULTS AND DISCUSSION

Flower blooms and fruit let count: At the beginning of the reproductive stage of tree, flower blooms were counted according to the as per the Table 1. Highest mean value of number of flower blooms was recorded in control (T4). The lowest mean value of number of flower blooms were recorded in T3. However, flower blooms count was not significantly different within treatments. Fruitlets count also showed the lowest mean value in T3. Fruitlets setting were same in T1 and T2. When comparing Table1 and Table 2, treatment 1 showed a failure in fruit set due to the wind damage or problem regarding pollination. However, fruitlet development was not significantly different in between treatments.

Table 1. Flower blooms fruit lets initiated as affected by different plant training systems Treatment Mean value of number of Mean value of number of fruit flower blooms /plant lets /plant T1 11.3 a 2.6b T2 7a 2.6b T3 6.6a 0.3b T4 11.6a 4a CV (%) 12.7 11.3 Note: Means followed by the same letter in each column are not significantly different at p=0.05

Table 2 shows the mean value of fruit yield of Apple from maturity stage to harvesting stage. Highest fruit yield was recorded in plants without use of any training systems. Lowest fruit yield was recorded in Treatment 3. Fruit yield also not significantly different within treatments.

256 NAYANA et al.

Table 2. Apple fruit yield from maturity stage to harvesting stage as affected by different training systems. Treatment Mean value of number of fruits / plant Mean value of number of fruits / plant (May 2013) (June 2013) T1 2a 1.3a T2 1a 1a T3 0a 0a T4 3a 2.3a CV (%) 26.9 24.6 Note: Means followed by the same letter in each column are not significantly different at p=0.05

Table 3 reveals that there is no significant different between treatments with any of the parameters measured in terms of quality of the fruit. In the context of TSS values of Apple fruits, highest value was evident in T3 with a comparatively low value in T4. When considering four treatments, there was a significantly different in brix values among fruits in different training systems. According to the literature, Bruce et al. (2008), reports that sugar content is changing with the different training systems of grapes. TSS formation is different with the amount of sunlight capture during the photosynthesis. The results revealed that higher sweetness can be obtained by adopting different training methods than without use of any training system.

According to the sensory evaluation results, Apple fruit taste was significantly different with each treatment (Table 4). A very clear difference in taste exist from highest to lowest in a sequence of T3, T1, T2 and T4. The results revealed that training systems of branches at angle 45 0 - 60 0 from vertical, excess flowers thinning and Centre open pruning methods are important to improve the Apple fruit taste. Sensory evaluation on colour of the fruit revealed that there is a significant difference between treatments. The T4 reported the significantly lowest mean value for colour (1.85). Greenish back ground with red colour was highest in T4 and other treatments were in golden colour back ground with red colour. The character of crispiness (mouth feel) of Apple fruits was significantly different between treatments. Treatments T3 and T2 reported the highest crispness. T1 and T4 were significantly lower in crispiness. Overall results revealed that the T3 has reported the highest value in taste; colour and mouth feel

FRUITING AND FRUIT QUALITY CHANGE THROUGH TRAINING OF APPLE 257

(crispiness). According to the literature Emily et al. (2009) has reported that flower thinning improves fruit quality by limiting number of fruits per cluster. Table 3. Fruit quality parameters of Apple as affected by different plant training systems. Treatment Mean value of fruit Mean value of fruit Mean pH value Mean TSS weight (g) firmness value T1 134.4a 3.1a 2.8a 15.2a T2 129.7ab 3.4a 2.7a 14.5a T3 93.6ab 3.3a 2.6a 15.5a T4 111.1ab 3.3a 2.7a 12.8b CV (%) 14.6 4.1 2.3 11.3 Note: Means followed by the same letter in each column are not significantly different at p=0.05

Table4. Sensory evaluation of Apple with different treatment. Treatment Taste Colour Mouth feel (Crispiness) T1 3.10b 2.7a 2.1b T2 2.30c 2.55a 2.9a T3 3.55a 2.9a 3.2a T4 1.05d 1.85b 1.8b CV% 10.2 8.3 6.8 Note: Means followed by the same letter in each column are not significantly different at p=0.05.

CONCLUSIONS

AgStat 2012. Pocket book of Agricultural Statistics. Volume X. Socio-Economic and Planning Centre, Department of Agriculture, Peradeniya, Sri Lanka. 42p. Bruce, W.Z., K.W. Tony, L. Pelanne, M.K. Miller and S.S. Birkenmaier 2008. Effect of vertical Shoot -Positioned, Smart Designed and Geneva Double - Curtain Training Systems on Viognier Grape and Wine Composition. Emily, E.H., E.S. Tepe and D. Foulk. 2009. Growing Apples in the homegarden, University of Minnesota. 27-28p.

Annals of Sri Lanka Department of Agriculture 2016. 18: 258-264

Short Communication

MOPHOMETRIC EVALUATION OF EXOTIC AND LOCAL RICE HYBRID

W.S. PRIYANTHA, D.M.O.K.B. DISSANAYAKE AND D.M.N.D.

DASANAYAKE

Rice Research & Development Institute, Batalagoda, Ibbagamuwa, Sri Lanka

INTRODUCTION Rice (Oryza sativa L.) is one of the world’s most important crops and is the staple food for near half the global population (FAO, 2004). Enhancement of rice production is important requirement to meet increasing demand for rice in future. Development of high yielding varieties with having multiple resistant to biotic and abiotic stress are important to cater the present and future changing environment. Hybrid rice technology is one of the options to enhance the productivity of rice. Hybrid rice technology assures the rice farmers with increased yield over improved conventional varieties by 15 to 20 % (Tran, 2002). In Sri Lanka, the research and development(R&D) programme on hybrid rice began in late 1994 at the Rice Research & Development Institute and have been able to identify several hybrids 1.0-1.5 t/h yield advantage over the best inbred grown under similar environments (Iqbal, 2009). However, limited genetic resources of parental lines (the Male sterile lines (CMS), Maintainers (B) and Restorers (R)) of hybrid rice programme was one of constrains at present and it directly affect the development of high heterotic hybrid combinations. Therefore, expansion of genetic diversity is important to develop better hybrid in future. In addition, testing of exotic hybrid combinations to identify their adaptability for local condition is one of options to expand the genetic materials of hybrid. Therefore, objective of this experiment was to study the performance and adaptability of exotic hybrid combinations for local conditions and compare their performance with locally developed hybrid combinations.

MATERIALS AND METHODS

The experiment was conducted to test four hybrid combinations for their yield performance and yield related components in Maha 2015/2016 at Rice Research & Development Institute (RRDI), Batalagoda. Two exotic hybrid combination (CH-1 and CH-2) from China were included along with 2 locally developed hybrid combinations (BgCMS4A/R147 and Bg407H). One high yielding restorer line (R16) and three inbred varieties under 3, 3anda ‘A and 4 months (Bg304, Bg357and Bg403) age group were included respectively as the stranded check. Experiment was established in a well

259 PRIYANTHA et al. prepared paddy field following randomized complete block design with four replicates. Eighteen days old seedlings were transplanted at 20 * 20 cm spacing. Seedling were placed one plant per one hill basis. Plot sizes were maintained 3* 6 m. Other agronomical practices were applied according to the Department of Agriculture (DOA) recommendations. Rainfall and average temperature of experimental field was recorded within the period of experiment was conducted.

RESULTS AND DISCUSSION

In this experiment, nine parameters were measured and presented Table 1 (yield,1000 grain weight (1000GW),fill grain (FG), unfiled grain(UFG), plant height (PH), productive tillers (PT), unproductive tillers (UPT), panicle length (PL), flag leaf length (FLL), flag leaf with (FLW) and days to 50 % flowering). Exotic two hybrid lines compared with 3 and a 3‘A months variety (Bg357). According to the yield data Bg407H obtained comparatively higher yield (4.09 t/h) but it was not significantly higher than its stranded check variety Bg 403. The highest 1000 GW (33.07 g) was shown by the CH-1 and it was significantly higher than all local inbred verities and local hybrid variety Bg407H. However, 1000 GW of CH-1 was similar to that of BgCMS4A/R147. Significantly higher FG obtained by R16 (247.8). But there was no significant difference of FG among CH-1, CH-2, BgCMS4A/R147 compared with their standard check variety Bg357. In addition, Bg407H, Bg304 and Bg 403 did not show significant FG number irrespective of their age. The lowest UFG was obtained (16.8) by Bg 403 and the highest by Bg407H. CH-1, CH-2, Bg CMS4A/R147 had shown significantly higher PH than their check variety Bg357. Meanwhile, the highest PH (111.7 cm) was shown by R16. CH-1 and CH-2 obtained significantly higher (3.95 and 2.44) UPT than the inbred variety, irrespective of their age. CH-1 and CH-2 obtained significantly high PL (24.8 cm and 25.15 cm) compared to stranded check Bg357 (22.1 cm). Meanwhile Bg 407H showed the highest PL (27.95 cm) but was not significantly higher than its stranded check variety Bg403 (26 cm). There was no significant difference of FLW of all the entries except Bg357, which showed the lowest FLL. There was no significant difference in FLL among all the tested entries. This experiment indicated that, tested exotic hybrid combinations (CH-1 and CH-2) did not obtain significantly higher performance on grain yield, FG, UFG, and FLW than the local hybrid and stranded check variety in same age group under local conditions in Maha 2015/2016. Meanwhile, these two hybrids showed significant higher performance of some traits (1000 GW, PH, PT, UPT, PL, and FLL) than stranded check Bg357. But out of these higher performing traits, yield component traits such as 1000 GW, FG, PT and PL, did not show much contribution to obtain higher yield than

MOPHOMETRIC EVALUATION OF EXOTIC AND LOCAL RICE 261 HYBRID the stranded check (Bg357) and local hybrid combination (BgCMS4A/R147) in same age group in tested season (Table 1).

SH = (F1-SC) x 100 SC

Where SH=Stranded Heterosis, F1 = Value of tested traits of hybrid, SC = Value of stranded check.

Stranded heterosis was estimated comparing CH-1, CH-2 and BgCMS4A/R147 with Bg 357(31/2 months) and Bg407H was compared with Bg403 (4 months). According to the estimated heteritic levels of all traits, CH-1 and CH-2 obtained 14.67 %, 3.66 % heterosis levels for yield respectively, not significantly higher than the heterosis level of local hybrid combination Bg CMS4A/R147 (15.8 %). Heterosis value of other yield components not positively affected to obtain the high heterosis such as filled grain, productive tillers and panicle length. Therefore, it indicated that tested exotic hybrid combinations did not perform well under local conditions in Maha 2015/2016 season. But comparison data of CH-1 and CH-2 in their native environment in China, showed highest yield 10.5 t/h and 9.95 t/h, respectively. Those yields are significantly different from that obtained in Sri Lanka (3.54 t/h, 3.27 t/h, respectively). In addition, those two hybrids took significantly longer duration for maturity; 142 days and 155 days, respectively. However, crop duration reduced under Sri Lankan condition (Table 3). Moreover, plant height and days to maturity also reduced in Sri Lankan condition. It indicated that, tested two hybrids showed poor performance out of their native environment and environmental effects highly affect to their performances. However, CH-1 and Bg CMS4A/R147 showed some potential level of heterosis 14.67 %, 15.83 %, respectively than CH-2 and Bg407H. Hence, this experiment should be repeated in next Yala (2016) to further study of these tested lines.

CONCLUSION

This experiment showed that tested two exotic hybrid combinations (CH-1, CH- 2) and local hybrid combinations (BgCMS4A/R147 and Bg407H) did not obtain the significant higher yield than their stranded check varieties (Bg357 and Bg403), respectively. These two exotic hybrid showed poor performance out of their native environment and did not obtain satisfactory level of heterosis (>15-20 %) in Maha 2015/2016 to select them for hybrid production in local conditions. But this experiment should be done to next Yala (2016) to further study and conformation of performance of these hybrid.

Table 1: Means comparisons of tested traits of treatments: Treatment Y(t/h) 1000 GW(g) FG UFG PH(cm) PT UPT PL(cm) FLL(cm) FLW(cm)

CH -1 3.5abc 29.3ab 126.4d 27.5abc 96.2d 5.9d 4a 24.8bc 29.3a 1.7ab

CH -2 3.3bc 33.1a 176.7b 17.3bc 108.4ab 5.9d 2.4ab 25.2bc 32a 1.6abc BgCMS4A/R14 3.6abc 29.8ab 145.7cd 28.3ab 98.9cd 8.5b 1.9bc 24.1bcd 29.4a 1.4bc Bg407H7 4.1a 28.2b 166bc 32.8a 103.6bc 9ab 1.8bc 28a 30.3a 1.5abc R16 3.9ab 23.1c 247.8a 25.1abc 111.7a 6.9cd 0.6c 25.4bc 30.1a 1.8a Bg357 3.2c 22.3c 156.7bc 18.1bc 82.2e 8.0bc 0.4c 22.1d 24.8b 1.5abc d Bg304 2.9c 22.9c 170.3bc 27.1abc 98.3cd 7.6bc 0.6c 23.4cd 30.7a 1.3c Bg403 4.1a 25.6bc 164.5bc 16.8c 99.2cd 10.3a 1.2bc 26.0ab 29.4a 1.5abc CV% 13.907 10.635 12.448 31.153 3.954 12.626 70.559 6.310 9.532 13.566 LSD 0.730 4.189 30.980 11.030 5.802 1.439 1.655 2.307 4.132 0.308 Y- Yield(t/ha), 1000GW- 1000 Grain weight, FG- Filled grain number, UFG- Unfilled grain, PH- Plant height, PT-Productive tillers, UPT Unproductive tillers, PL-Panicle length, FLL-Flag leaf length, FLW-Fag leaf width, 50%F-days to50% flowering

Table 2: Standard Heterosis (%)of tested hybrid combinations in

Combinations Y FG CH -I 14.67a -16.30b CH -2 3.66a 15.85a BgCMS4A/R14 15.83a -5.82ab Bg407H7 1.49a 0.56ab LSD 29.65 25.17

Y- Yield, FG-Filled grain, UFG- Unfilled grain, PH

Table 3: Comparison of some plant characters of CH

In China CH 1 In Sri Lanka CH 1 Plant characters Age 142 Y( t/h) 10.5 DM 30 -35 SH (cm) 124 TT 12 FLL (cm) 27 FLW (cm) 1.5 PL( cm) 27 1000GW( g) 32 Unproductive tillers, PL-Panicle length, FLL

DM-Date to maturity, Y-Yield, SH-Stem height, TT width, PL-Panicle length, 1000 grain weight; * difference.

264 PRIYANTHA et al.

REFERENCES

Dorosti, H. and Monajjem, S. 2014. Gene action and combining ability for grain yield and yield related traits in rice. FAO.2004. the state of food and agriculture 2003-04. Agriculture biotechnology: Meeting the needs of the poor? FAO Agriculture series No. 35.Food and Agriculture Organization of the United Nations, Rome. Iqbal, Y.B. 2009. Analysis of combining ability to identify suitable parents for heteritic rice breeding. Tran, D.V. 2002. Hybrid rice large for food and security: recent progress and large scale production issues. In: Proceedings of the workshop on policy support for rapid adaptation of hybrid rice on large scale production in Asia, Hanoi, Vietnam, 22-23 may 2001.

Annals of Sri Lanka Department of Agriculture 2016. 18: 265 - 269 Short Communication

RESPONSE OF RICE AND WEEDS TO EARLY SUBMERGENCE IN DIRECT SEEDED RICE IN SRI LANKA

H.M.S HERATH 1, R.F. HAFEEL 1, R.S.K. KEERTHISENA 2 AND A.P. BENTOTA 2

1 Rice Research Station, Ambalantota, Sri Lanka 2 Rice Research and Development Institute, Batalagoda, Sri Lanka

INTRODUCTION

Weeds are the major biological constraint to successful rice cultivation and high weed density causes high risk of yield loss in direct-seeded rice (DSR) (Herath et al, 1998; Rao et al., 2007). Herbicides are intensively used to reduce the high weed pressure (Raoet al., 2007; Weerakoon et al., 2011) but dependency on herbicides increases the risk of development of herbicide resistance in weeds (Rao et al., 2007).Poor weed control efficacy of herbicide dominant system is accompanied with the incorrect use, lack of requisite knowledge and skill to use herbicides in Sri Lanka. This has increased interest in the use of alternative weed management approaches to achieve successful weed control in DSR system. Appropriate water management at crop establishment plays a key role in weed management in DSR (Rao et al., 2007).Although flooding is known as a viable tool for weed management in rice, it aggravates the poor crop establishment. One viable strategy to avoid conflict among crop stand establishment and early water management in DSR is to use of submergence tolerant rice varieties. Screening of submergence tolerant rice varieties could offer an opportunity for using them as a component of integrated weed management strategy in DSR. Therefore, this study was conducted to evaluate the submergence tolerant ability and yield potential of popular rice varieties for use in integrated weed management strategies in DSR and to determine weed control percentage under submerged condition.

MATERIALS AND METHODS

Field experiment was conducted in Rice Research Station, Ambalantota during 2015/16 Maha season. The experiment was established in a split-plot design with three replicates. The main plot included two level of submergence depth (0 cm and 5 cm) and sub plot (3m x 3m) withfifteen rice varieties; At 307, At 308, At 354, At 362, Bg 300, Bg 94/1, Bg 379/2, Bg 455, H4, Bg 352, Bg 360, Bw 367, Bw 372, Ld 368 and Ld

266 HERATH et al.

371.Seeds soaked for 48 hours and incubated for 24 hours were sown either to plots with puddled saturated soil without standing water or on to plots with 5 cm water depth and the water depth was maintained for 21 days (submergence treatment). Two quadrates of 0.25m 2 size were placed at random in each plot to determine rice seedling density, weed density and biomass content at 4 weeks after sowing (WAS) and at 6WAS. Weeds were counted and classified into species and grouped into grasses, broad leaves and sedges and oven dried to determine weed biomass. Grain yield was measured from an area of 9 m 2 per plot.

Data were subjected to analysis of variance (ANOVA) using STAR for Windows version 2.1 (IRRI, 2014). Differences among treatments were compared using least significant differences (LSD). Relationships between grain yield (t/ha) and different attributes were determined using linear regression.

RESULTS AND DISCUSSION

Weed density and biomass Grass and sedge weed densities (Figure 1A) and biomass (Figure 1B) were significantly lower in the submerged treatment compared to the saturated treatment at 6 WAS. Biomass reduction of grasses and sedges under submerged conditions at 6 WAS were 84% and 72%, respectively. But, broad leaf weed density and biomass were significantly higher under submerged condition. The reduction of grasses and sedge density might be due to suppressed germination ability under anaerobic conditions. Results showed that submergence to 5 cm flooding is effective to control grasses and emerging problematic sedgessuch as Cyperus difformis and Cyperus irri. Venkataraman and Gopalan (2005) showed that, continuous submergence to 5 cm flooding minimizes the grass weed density in rice field. Further, David (1992) reported that 8 cm water depth declined many grass and sedge weeds densities and 16 cm water depth totally reduced the emergence of above weed groups. Results revealed that saturated condition has favoured the germination and growth of three groups of weeds. Meanwhile submerged condition has significantly reduced the density and growth of grasses and sedges. Therefore, submergence could be suggested as the eco- friendly weed control method which can be included in the integrated weed management package to enhance the weed management in DSR while reducing herbicide dependency.

A200 ■ Saturated □ Submerged B 200 ■ Saturated □ Submerged a

Grass Broadleaf Sedges Group of Grass Broadleaf Sedges weeds Group of weeds RESPONSE OF RICE AND WEEDS TO EARLY SUBMERGENCE 267

Figure.1: Variation of grasses, broad leaf and sedges density (A) and biomass (B) under submerged and saturated condition across varieties at 6 WAS. Different letters indicate significant differences (P< 0.05) according to LSD.05 .

Rice seedling density and yield: Seedling count of all rice varieties had reduced under submergence treatment compared to the saturated condition at 4 WAS (Figure 2). Among them, Bw 367, At 362 and Bg 455 recorded lowest reduction in seedling count of 5, 17 and 27%, respectively. Higher grain yield was recorded under the submerged condition compared to saturated condition (Figure 3). I Submerged 600 I Submerged 6 0

§00 - i = o

0 in as r-- 00

At 362 attained the highest gain yield followed by Bw 367, At 308 and At 307 and Bg 455 under submerged condition. The reduction of grain yield under saturated condition might be due to high weed pressure compared to that under submerged condition. These results were further supported by the significant negative correlations with grain yield and sedges count and dry weight and grass dry weight at 6 WAS under saturated condition (Table 1). These results are in agreement with the results of Ismaila et al. (2015) who reported that significantly higher yield of rice was observed under submerged condition than saturated condition due to less weed competition. In submerged condition, grain yield was positively correlated with rice plant count, whereas,

268 HERATH et al. negatively correlated with the broadleaf weed count. These results show that rice plant count is the main important parameter to increase yield under submerged condition. Table 1. Correlation among different traits in saturated condition. Traits GY GDW BLDW SEDW GC BC GDW -0.086 1 BLDW 0.245 0.262 1 SEDW -0.365* -0.079 -0.362* 1

GC 0.629*** 0.173 -0.282 0.1641 1 BC 0.064 -0.093 0.294* 0.0446 0.011 1

SC 0.556*** -0.006 -0.279 0.385** 0.521*** -0.074

***, **, * significant at P< 0.001, P< 0.01 and P< 0.05 respectively. GY, grain yield; GDW, grass dry weight at 6 WAS; BLDW, broad leaf dry weight at 6 WAS; SEDW, sedges dry weight at 6WAS; GC, grass count at 6 WAS; BC, broad leaf count at 6 WAS and SC, sedges count at 6 WAS.

CONCLUSION

Study shows that rice varieties, At 362, Bw 367, At 308 and At 307 and Bg 455 had higher seedling count and higher yield under submerged condition and those rice varieties are more suitable for submerged condition. Submergence to 5 cm water depth reduces grasses and sedges biomass by 84% and 72%.Therefore, this study highlighted the use of tolerant rice genotypes to ensure the crop establishment under submerged conditions and management of grassy and sedges weed using the early submergence in DSR.

REFERENCES

David, C. 1992. Rice in deep water. IRRI. Macmillan press limited. pp. 441-446. Herath Banda, R.M., Dhanapala, M.P., Silva, G.A.C Hossain, M.1998.Constraints to increase rice production in Sri Lanka. Workshop prioritization of Rice Research. International Rice Research Institute, Philippines, in press. International Rice Research Institute. 2014. IRRISTAR for Windows Version 2.0.1. Los Bano s, Philippines. Ismaila, U., Kolo, M. G. M., Odofin, A. J., & Gana, A. S. 2015. Effects of Water Depth and Seedling Rate on Weed Control and Yield of Late Season Lowland Rice (Oryza sativa L). Journal of Plant Studies, 4(2), 92. Rao, A.N., Johnson, D.E., Sivaprasad, B., Ladha, J.K., Mortimer and A.M.. 2007. Weed management in direct-seeded rice. Advances in Agronomy 93:153-255. Venkataraman, N.S., & Gopalan, M. 1995. Current status of weed problem in rice production in Tamil Nadu, India. Paper presented at a Workshop on Weed Management in Rice Production, 19-23 June 1995, IRRI-MARDI, Pulau Pinang, Malaysia, 24.33.

RESPONSE OF RICE AND WEEDS TO EARLY SUBMERGENCE 269

Weerakoon, W.M.W., M.M.P. Mutunayake, C. Bandara, A.N. Rao, D.C. Bhandari and J.K. Ladha. 2011. Direct-seeded rice culture in Sri Lanka: Lessons from farmers. Field Crops Res. 121: 53-63.

Annals of Sri Lanka Department ofAgriculture 2016. 18: 300

List of Paper Reviewers

Prof. A.N. Jayakody Department of Soil Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Prof. L.H.P. Gunarathne Department of Agriculture Economics, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. S. Kumar Department of Agriculture Economics, Faculty of Agriculture, University of Peradeniya, Peradeniya

Ms. Indra Wahundeniya No. 72/27, Damunupola Mawatha, Kandy

Ms. K.S.W.B.L.D. Galanihe No. 5/12, Gemunu Mawatha, Hantana Place, Kandy

Dr. L. Nugaliyadda 1/75, Batuambe Road, Nugawela, Kandy Dr. Saman Dharmakeerthi Department of Soil Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Prof.(Ms) Devika De Costa Department of Agriculture Biology, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr.(Ms) Warshi Dandeniya Department of Soil Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. K.A. Meththananda 303 C1, Dengamuwawatta, Madarariyagoda, Kadugannawa Dr.(Ms) Janaki Mohotti Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Prof. Janendra De Costa Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. D.B. L. Suriyagoda Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr. Shanthi Wilson 10A 1/1, Skelton road, Colombo 05

301

Prof.(Ms) K.M.S. Wimalasiri Department of Food science, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr.(Ms) Jinadari De Soyza 72/B/1, Malwaththa Road, Asgiriya, Gampaha Prof. S.P. Nissanka Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. W.A.U. Vitharana Department of Soil Science, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr. W.M.A.D.B. 227/4, Wijesiri Mawatha, Dadahogama, Kulugammana Wickramasinghe Prof. (Ms) Janaki Easwara Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. (Ms) Shelomi Krishnarajah Senior Research Officer, National Botanical Gardens, Peradeniya Prof. Buddhi Marambe Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr.(Ms) Ramya Fonseka Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr. Sumith Abesiriwardana CIC Agriculture, Pelwehera, Dambulla Prof. Palitha Weerakkoddy Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. J.P. Keerthisinghe Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. B.D.R. Prasantha Department of Food Science, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr. (Ms) Mangalika Department of Agriculture Biology, Faculty of Wickramasinghe Agriculture, University of Peradeniya, Peradeniya

Dr. Wasantha Chitral 100A, Ganhatha road, Kirinda, Weligalla

302

Prof. (Ms) R.M.C.P. Department of Soil Science, Faculty of Agriculture, Rajapaksha University of Peradeniya, Peradeniya Dr. (Ms) Eresha Mendis Department of Food Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. Niranjan Rajapaksha Department of Food Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. Keerthi Mohotti Deputy Director (Production), Tea research Institute of Sri Lanka, St. Coombs, Talawakelle Prof. R.B. Mapa Department of Soil Science, Faculty of Agriculture, University of Peradeniya Prof. Nimal Adikaram Department of Botany, Faculty of Science, University of Peradeniya, Peradeniya Prof. M.I.M. Mowjood Department of Agriculture. Engineering, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr. H.B. Nayakakorala 89/1, Gampola Road, Meewathura, Peradeniya Prof. (Ms) N.D.K. Dayawansa Department of Agriulture Engineering, Faculty of Agriculture, University of Peradeniya, Peradeniya Mr. S.N. Jayawardena 376/1, 2 nd lane, Othukubura Mawatha, Wilgoda road, Kurunegala Prof. T. Sivananthawal Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. (Ms) Pradeepa Liyanage Tea research Institute of Sri Lanka, St. Coombs, Talawakelle Prof. Nimal Gunawardena Department of Agriculture Engineering, Faculty of Agriculture, University of Peradeniya, Peradeniya

Prof. (Ms) A. Navaratne Department of Chmistry, Faculty of Science, University of Peradeniya, Peradeniya

303

Prof. Nimal Dharmasena Department of Agriculture Engineering, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. W. M. T. Ariyaratne Department of Crop Science, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. Nimal Dissanayake No 10, Preethi Mawatha, Mahaweli Uyana, Watapuluwa, Kandy Prof. V.A. Sumanasinghe Department of Agric. bIology, Faculty of Agriculture, University of Peradeniya, Peradeniya

Mr. R.S. Yahajeewa de Silva Gunamuni Niwasa, Godagama, Kosgoda

Dr. Venura Herath Department of Agriculture BIology, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr. S. Pathmaraja Department of Agriculture Engineering, Faculty of Agriculture, University of Peradeniya, Peradeniya Dr.(Ms) Inoka Kudawithanage Senior Lecturer, Faculty of Applied Science, University of Sabaragamuwa, Belihuloya Dr. T. Madhujith Department of Food Science, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr. Sarath Amarasiri 57 A, Godagandeniya, Pereradeniya Prof. Lasantha Manawadu Department of Geography, Faculty of Arts, University of Colombo, Colombo - 2.

Ms. (Ms) Shiromani Department of Meteorology, Bauddhaloka Mawatha, Jayawardana Colombo-7 Prof. Jeewika Weerahewa Department of Agriculture Economics, Faculty of Agriculture, University of Peradeniya, Peradeniya

Dr. M.P. Dhanapala Vijayathpaya, Owitigama, Pugoda Mr. Ananda Pathirage Managing Director, HJS Condiments Ltd, Block 61, 62, & 63, Biyagama Export Processing Zone, Biyagama,

304

Dr. P. Weerasinghe Additional Director (Research), Horticulture Research and Development Institute, Department of Agriculture, Gannoruwa, Peradeniya Mr. K.M.A. Kendaragama Deputy Director (Research), Natural Resource Management Centre, Department of Agriculture, Peradeniya Dr. (Ms). Lakmini Priyantha Deputy Director (Research), Seed Certification & Plant Protection Centre, Department of Agriculture, Gannoruwa, Peradeniya Mr. D.N. Sirisena Deputy Director (Research), Rice Research and Development Institute, Department of Agriculture, Bathalagoda Dr. R.M. Herath Deputy Director, Socio-Economic & Planning Centre, Department of Agriculture, Peradeniya Dr. Gamini Samarasinghe Deputy Director (Research), Plant Genetic Resources Centre, Department of Agriculture, Gannoruwa, Peradeniya Dr. K. Hettiarachchi Director (Research), Seed Certification & Plant Protection Centre, Department of Agriculture, Gannoruwa, Peradeniya Dr. Jayantha Senanayake Additional Director, National Plant Quarantine Service, Katunayake Dr. R.G.A.S. Rajapakshe Additional Director, Horticulture Research and Development Institute, Department of Agriculture, Gannoruwa, Peradeniya Dr. W.M.W. Weerakoon Director, Field Crop Research and Development Institute, Mahailluppallama Dr. J.A. Sumith Registrar of Pesticide, Office of the Registrar of Pesticide, Gatabe, Peradeniya

305 Dr. K.H. Sarananda Head, Food Research Unit, Peradeniya Mr. A.G.C. Babu District Director of Agriculture, District Secretariat, Nuwara Eliya Dr. (Ms) Samanthi Wasala Assistant Director (Research), Plant Genetic Resources Centre, Department of Agriculture, Gannoruwa, Peradeniya Dr Hemal Fonseka Director, Horticulture Research and Development Institute, Department of Agriculture, Gannoruwa, Peradeniya Dr. (Ms) Amitha Bentota Director, Rice Research and Development Institute, Department of Agriculture, Bathalagoda Dr. S.J. Arsakesary Additional Director, Regional Agriculture Research and Development Centre, Kilinochchi Mr. M.A.K. Munasinghe Additional Director, Natural Resource Management Centre, Department of Agriculture, Peradeniya Dr. S.H.S.A. De Silva Director, Natural Resource Management Centre, Department of Agriculture, Peradeniya

Annals of Sri Lanka Department of Agriculture 2016. 18 : 306

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Bonks (identical author and editor) Dc Datta, S.K. 1981. Principles and practices of rice production. John Wiley and Sons, New York.

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Tltesis Piepcr, R.D. 1963. Production and chemical composition of arctic tundra vegetation and their relation to tire lemming cycle. Unpublished Pbjj. Thesis. University of Peradeniya, Peradeniya, Sri Lanka.

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