E:Review article-- 20034--Chhavi

Indian Journal of Entomology, Review Article (2020) DoI No.:

ESTIMATION OF DAMAGE AND YIELD LOSSES BY THE LEAF FOLDER MEDINALIS (GUENEE) AT PANICLE INITIATION STAGE

Chhavi*, Pawan K. Sharma and Ajai Srivastava

Department of Entomology, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishwavidyalaya, Palampur 176062 *Email: [email protected] (corresponding author)

ABSTRACT

Rice leaf folder larvae at population levels 0, 2, 4, 6, 8 and 10 larvae/ were released at panicle initiation stage to assess damage and yield loss. The maximum leaf damage was 24.5% with 10 larvae/ hill, and the least (6.9%) at 2 larvae/ hill. The avoidable losses at population levels of 2, 4, 6, 8 and 10 larvae per hill at panicle initiation were 0.9%, 6.4%, 14.8%, 23.4% and 28.9%, respectively. Grain yield at 2 larvae/hill was found to be at par with pest free level. The linear regression equation obtained between grain yield and population levels of larvae revealed that a unit per cent increase in damage resulted in yield reduction to the extent of 0.5 g/ hill. Drastic decrease in yield was observed with increase in population above 4 larvae/ hill, which indicated that economic threshold level for rice leaf folder should be two larvae/ hill.

Key words: Avoidable losses, damaged leaves, grain yield, leaf folder, panicle initiation, population levels, rice, regression, economic threshold

Rice is one of the most important cereal crops, and grown on well prepared raised beds and about 25-30 India with the largest area (43.99 million ha) ranks days old seedlings were transplanted to main field at second in its production with 109.70 mt (Anonymous, a spacing of 20x 15 cm in the plots of 4 x 3 m each 2018a). Himachal Pradesh occupies third position with during 2015 and 2016. There were six treatments production of 135.48 thousand mt (Anonymous, 2018b; including control and replicated five times laid down Anonymous, 2018c). One of the major constraints in in Randomized Block Design (RBD). Different levels obtaining the yield potential from the newly evolved rice i.e. 0, 2, 4, 6, 8 and 10 larvae/ hill released at panicle varieties is the 30% loss caused by pests (Kumar initiation stage constituted the treatments and damage et al., 2013). More than 100 pests attack the rice crop, expressed in %. Chlorpyriphos @ 2.5 ml/ l and fungicide out of which 20 are of major economic significance. (Blitox 50 @ 3g/ l) were applied 20 days before release The rice leaf folder, Cnaphalocrocis medinalis (Guenee) of larvae to avoid other pests. The procedure followed hither to considered as a minor pest, has assumed major by Directorate of Rice Research, Hyderabad was used pest status (Nanda et al., 2000). Its severe infestation for yield loss estimation (Anonymous, 2014). Four rice leads to 60-70% leaf damage with yield loss varying hills selected and marked served as one replication. from 30 to 80% (Nanda and Bisoi, 1990), while These hills were covered with nylon net supported using Shanmugam et al. (2006) reported 11.18% loss. In four bamboo sticks. Pretreatment data were recorded general, yield loss in rice depends on pest population on total number of leaves and number of damaged density and plant growth stage at the time of attack. It leaves before enclosing the hills. Each treatment was is very important to understand the relationship between then infested with indicated population levels at panicle pest population density and yield losses. No work has initiation stage obtained from a mass culture maintained been done in Himachal Pradesh regarding the extent in the laboratory. The cages were removed after 10 of losses incurred due to this pest at varied population days and damage caused observed by counting the total levels. Present studyPREVIEW was conducted to work out the number and damaged leaves on a day immediately after extent of yield losses caused at various population levels the removal of net followed by 10 days after the second of rice leaf folder larval instars. reading i.e. at 60 and 70 days after transplanting (DAT). The panicles from four hills/ replication were harvested MATERIALS AND METHODS at maturity for recording yield. These panicles were Rice nursery was raised at the Rice and threshed, cleaned and weighed. The avoidable yield Research Centre, Malan (Kangra), with variety Kasturi losses were worked out following Atwal and Singh 2 Indian Journal of Entomology, Review Article 2020

(1990). The relationship between yield and damaged larvae/ hill at the damage of 24.9% at 10 larvae/ hill, leaves were subjected to analysis for critical variance or respectively. Drastic decrease in yield was observed difference through CPCS-1 software following Gomez with >4 larvae/ hill (Fig. 1). These results derive support and Gomez (1984). from those of Wareing et al. (1968) and Asghar et al. (2009). Jiang et al. (2014) observed no significant RESULTS AND DISCUSSION differences in rice yield when 1, 2 and 4 larvae/ hill. In The data on damaged leaves revealed significant both the years, grain yield at 2 larvae/ hill was found variations amongst population levels of leaf folder to be at par with pest free level concluding that the larvae (Table 1). During 2015, the damage varied control measures should be adopted at this economic from 5.1 to 25.3%, while in 2016, it was 5.8 to 27.2%. threshold level. Tu et al. (1985) and Arshad et al. (2012) The pooled mean revealed a maximum damage of determined economic threshold level for rice leaf folder 24.4% at the population level of 10 larvae/ hill and equal to 3 and 2 larvae/ hill, respectively. lowest at 2 larvae/ hill (6.9%). Damage during 2016 The linear regression equation given in Fig. 2 was significantly more at 60 and 70 DAT (Table 1). revealed that a unit increase in infestation resulted Between two different intervals of observations, mean in reduction in yield to the extent of 0.5 g per hill. damage was significantly higher at 70 DAT (13.8%) Correlation coefficient ‘r’ value was found to be over 60 DAT (11.0%). While no damage was observed at pest free level, damage increased significantly with the incremental population levels and was the highest at 10 larvae/ hill (Table 1).

The grain yield decreased with increasing population levels (Table 2); it was minimum at 10 larvae/ hill (10.4 g/ hill), where damaged leaves were 23.9%, and the highest yield (15.1 g/ hill) was obtained in the treatment with no infestation. During 2016, similar trend was observed with highest (14.9 g/ hill) and lowest grain yield (10.8 g/ hill) at population levels 0 and 10 Fig. 2. Linear regression analysis between yield and population levels of C. medinalis larvae at panicle initiation

significantly negatively correlated (r= -0.950), which indicated that with increase in infestation levels there was decrease in yield. Similar findings were observed by Ahmad et al. (2010); Mahal et al. (2011) also observed such a positive relationship. The avoidable losses at the evaluated population levels varied from 0.6 to 31.5 and 1.3 to 27.2% during 2015 and 2016, respectively, with the minimum and maximum values corresponding to population levels of 2 and 10 larvae/ hill (Table 2). Thesw findings are in close conformity with the results of Ahmad et al. (2010), who reported that yield loss varied from 2.1 to 23.4%. Leaf damage increased significantly with the increasing population levels of leaf folder. Drastic decrease in yield was observed with increase in population levels above 4 larvae/ hill, which PREVIEWsignifies that control measures should be adopted before this. Management of leaf folder with use of insecticides should be adopted when two larvae/ hill are noticed.

ACKNOWLEDGEMENTS

Fig. 1. Relationship between population levels of C. medinalis The first author acknowledges the help received larvae, damaged leaves and yield from the Professor and Head of the Department of 3 Indian Journal of Entomology, Review Article 2020 - - 0.9 6.4 28.9 14.8 23.4 losses Avoidable Avoidable Mean 0.0 (1.0) 6.9 (15.2) 9.8 (18.2) 14.4 (22.3) 19.4 (25.9) 24.5 (29.5) - q/ ha 50.9 50.5 47.7 36.2 43.5 39.1 g/ hill Grain yield 11.5 15.0 14.9 14.0 10.6 12.8 (3.9) (3.9) (3.9) (3.4) (3.8) (3.5) 2016 0.0 (1.0) 7.4 (15.7) 9.5 (17.9) 14.6 (22.4) 19.3 (26.0) 24.9 (29.9) 12.6 (18.7) - - 1.3 6.0 27.2 15.6 24.1 2016 2015 11.3 14.7 13.9 14.9 13.0 10.9 12.6 (3.9) (3.9) (3.9) (3.8) (3.4) (3.7) (3.6) Damaged leaves (%) 0.0 (1.0) 6.5 (14.7) 10.0 (18.4) 14.3 (22.2) 19.4 (25.7) 23.9 (28.9) 12.2 (18.3) : 0.039 : 0.068 : 0.096 Yield and avoidable loss** Yield - - 0.6 6.8 22.7 31.5 13.9 : 0.014 : 0.024 : 0.034

2015 11.7 15.0 13.2 14.1 15.1 10.4 13.0 (4.0) (3.8) (3.9) (4.0) (3.6) (3.4) (3.7) 0 2 4 6 8 10 Mean CD p= 0.05 A) Year Population (C) A×C Larvae (No./hill) CD (p= 0.05) Years(A) Population levels (B) A×B all 6.9 9.8 0.0 19.4 24.5 14.4 (1.0) Over mean (15.2) (18.2) (25.9) (29.5) (22.3) 7.4 9.5 0.0 12.6 19.3 24.9 14.6 (1.0) Mean (15.7) (17.9) (18.7) (26.0) (29.9) (22.4) 8.9 0.0 10.9 14.0 20.8 27.2 16.1 (1.0) (17.4) (19.3) (19.8) (27.1) (31.4) (23.7) 2016 70 DAT : 0.056 : 0.096 : 0.096 : 0.136 5.8 8.2 0.0 11.3 17.8 22.7 13.0 (1.0) (13.9) (16.6) (17.5) (24.9) (28.5) (21.1) 60 DAT A×B A×C B×C A×B×C 11.0 13.8 Mean (17.3) (19.7) 6.5 0.0 10.0 12.2 19.4 23.9 14.3 (1.0) Mean (14.7) (18.4) (18.3) (25.7) (28.9) (22.2) Damaged leaves (%)* 11.3 14.0 12.6 2016 (17.5) (19.8) (18.7) 70 7.9 0.0 11.5 2015 13.7 21.5 25.3 15.7 (1.0) DAT (16.3) (19.9) (19.5) (27.6) (30.2) (23.3) : 0.039 : 0.039 : 0.068 Table 1. Effect of C. medinalis- larvae at panicle initiation stage, damage and their interactions 1. Effect Table

: : 10.7 13.7 12.2 60 2015 8.5 5.1 0.0 Damaged leaves (%) 0.039 0.039 (17.1) (19.5) (18.3) : 0.056 12.9 10.7 16.3 21.7 (1.0) DAT (16.9) (13.0) (17.1) (23.8) (27.7) PREVIEW(21.1) levels

(No./ hill) Population CD (P= 0.05) 4 2 DAT A×B 6 0 Year (A) Year Mean 8 10 Days after transplanting (B) 60 Population levels C) levels Population 70 Mean CD (p=0.05) (A) Year (B) DAT Interaction – damage x DAT - No. of larvae vs. year Interaction – damage x DAT *Figures in parentheses arc sine transformed values; ** square root transformed values; values; transformed root ** square values; transformed sine arc in parentheses *Figures transplanting after Days DAT: 4 Indian Journal of Entomology, Review Article 2020 - - 0.9 6.4 14.8 23.4 28.9 losses (%) Mean avoidable - 50.9 50.5 47.7 43.5 39.1 36.2 Mean grain yield (q/ha) C. medinalis larvae 11.5 15.0 14.9 14.0 12.8 10.6 (3.9) (3.9) (3.9) (3.8) (3.5) (3.4) Mean grain yield (g/hill) - - 1.3 6.0 (%) 15.6 24.1 27.2 Avoidable losses Avoidable 2016 Yield and Avoidable losses Avoidable and Yield 11.3 13.0 14.9 14.7 13.9 12.6 10.9 (3.8) (3.9) (3.9) (3.9) (3.7) (3.6) (3.4) Yield (g/ hill) Yield - - 0.6 6.8 (%) 13.9 22.7 31.5 2015 Avoidable losses Avoidable

11.7 13.2 15.1 15.0 14.1 13.0 10.4 (3.8) (4.0) (4.0) (3.9) (3.7) (3.6) (3.4) Yield (g/ hill) : 0.014 : 0.024 : 0.034 PREVIEW and per cent avoidable losses obtained at various population levels of Yield 2. Table

Population levels (B) A×B 0 Population levels (No./ hill) Mean (A) Years CD (P= 0.05) 2 4 6 8 10 Figures in parentheses are the square root transformed values Estimation of damage and yield losses by the rice leaf folder Cnaphalocrocis medinalis (Guenee) at panicle initiation stage 5 Chhavi et al.

Entomology and Scientist In-charge of the Rice Atwal A S, Singh B. 1990. Pest population and assessment of crop losses, and Wheat Research Center, Malan at CSKHPKV, Indian Agricultural Research Institute, New Delhi. p. 107. Palampur. Gomez K A, Gomez A A. 1984. Statistical Procedures for Agricultural Research, 2nd ed. John Wiley and Sons, New York. p 680. REFERENCES Jiang L, Zhu Z, Ge L, Yang G, Wu J. 2014. Rice grain damage by combination and sequence infestations by rice leaf folder, Ahmad H, Khan R B, Sharma D, Jamwal V V S, Srivastava K. 2010. Cnaphalocrocis medinalis Guenee (: Pyralidae), and Assessment of yield infestation relationship of Cnaphalocrocis the white backed rice planthopper, Sogatella furcifera Horvath medinalis in rice. Annals of Plant Protection Sciences 18: 489-490. (Hemiptera: Delphacidae). Journal of Integrative Agriculture 13: 2460-2470. Anonymous. 2018a. Pocket book of Agricultural Statistics. Department of Agriculture, Cooperation and Farmers Welfare. Directorate of Kumar A, Singh B, Singh M, Jaglan M S. 2013. Population dynamics Economics and Statistics, Government of India, New Delhi. pp. of rice leaf folder Cnaphalocrocis medinalis (Guenee) under 44-48. agroclimatic conditions of Haryana. Research in Plant Biology 3: 40-45. Anonymous. 2018b. Economic survey of Himachal Pradesh. Economics and Statistical Department. Government of Himachal Pradesh, Mahal M S, Kajal V K, Kaur R, Singh R. 2006. Integration of chemical Shimla. p. 44. and biocontrol approaches for the management of leaf folder, Cnaphalocrocrocis medinalis Guenee and stem borer, Scirpophaga Anonymous. 2018c. Statistical Abstract of Himachal Pradesh. Economics incertulas Walker on Basmati rice. Journal of Biological Control and Statistical Department. Government of Himachal Pradesh, 20: 1-6. Shimla. p. 43. Nanda U K, Mahapatro G K, Sahoo A, Mahapatra S C. 2000. Rice leaf Anonymous. 2014. All India Coordinated Rice Improvement Programme folder: Integrated neem derivatives in its management. Pestology (Entomology Technical Programme), ICAR- Directorate of Rice 24: 31-34. Research, Rajendranagar, Hyderabad. pp. 30-31. Nanda V K, Bisoi R C. 1990. Bionomics of rice leaf folder, Arshad M, Suhail A, Majeed M M, Arif M J, Bilal H, Gogi M D, Abdin Cnaphalocrocis medinalis. Orissa Journal of Agricultural Research Z, Bashir M H. 2012. Determination of economic threshold level 3: 130-135. (ETL) for the chemical control of rice leaf folder, Cnaphalocrocis medinalis (Pyralidae: Lepidoptera). Pakistan Entomologist 34: Shanmugam T R, Sendhil R, Thirumalvalavan V V. 2006. Quantification 79-81. and prioritization of constraints causing yield loss in rice () in India. Agricultura Tropica et Subtropica 39: 194-201. Asghar M A, Suhail M, Afzal, Khan M A. 2009. Determination of economic threshold levels for the stem borers (Scirpophaga sp.) Tu C W, Wang F M, Hu J Z, Chen Y L, Zheng J A, Cao B C. 1985. The and leaf folder (Cnaphalocrocis medinalis) of rice (Oryza sativa) technical practicality of the integrated control of diseases and pests in the Kallar tracts of Punjab, Pakistan. International Journal of of rice. Scientia Agricultura Sinica 2: 85-87. Agriculture and Biology 11: 717-720. Wareing P F, Khalifa M M, Treharne K J. 1968. Rate limiting process in photosynthesis at saturating light intensities. Nature 220: 453-457.

(Manuscript Received: January, 2020; Revised: April, 2020; Accepted: April, 2020; Online Published: April, 2020) Online published (Preview) in www.entosocindia.org Ref. No. 20034 PREVIEW