Journal of Scientific & Industrial Research Vol. 76, October 2017, pp. 654-661 Studies on Effect of Grafting Technique on Growth and Yield of Bitter Gourd (Momordica Charantia L.) N A Tamilselvi1* and L Pugalendhi2 *1Department of Vegetable Crops, Horticulture College and Research Institute, Tamil Nadu Agricultural University, Coimbatore-641 003, Tamil Nadu 2Horticultural Research Station, Yearcaud-636 601 Tamil Nadu Received 14 August 2016; revised 17 April 2017; accepted 22 August 2017 The experiment was conducted during 2012-14 to study the effect of grafting technique with different rootstocks on growth and yield of bitter gourd (Momordica charantia L.) by comparing grafted bitter gourd plants with non-grafted (intact) plants under field conditions. The bitter gourd cultivars viz., Palee F1 and CO 1 were grafted onto six cucurbitaceous rootstocks by adopting side grafting method. At 15 days after grafting, the bitter gourd scions grafted with pumpkin (Cucurbita moschata) and sponge gourd (Luffa cylindrica) rootstocks recorded the higher success percentage (89.05 and 85.35) than other graft combinations. The result revealed that, the grafted plants had better vegetative growth and yield than the non-grafted plants (check). Highest vegetative growth (844.26 cm), least node number to first female flower appearance (25.80), narrow sex ratio (17.89) number more fruit number (28.02 fruits) and fruit yield per vine (3.55 kg/vine) were observed in Palee F1 scion grafted onto ‘pumpkin (Cucurbita moschata)’ rootstock than other graft combinations and non-grafted plants. The differences recorded for growth and yield of the tested cultivars might be due to different growth characteristics, graft affinity and compatibility. This evidence indicates that grafting bitter gourd scions onto specific rootstock significantly influences growth and yield without deterioration in the fruit quality. Keywords: Grafting, Bitter Gourd, Rootstocks, Yield, Cucurbita moschata, Luffa cylindrica Introduction Materials and methods Bitter gourd (Momordica charantia L.) is one of Experimental site and growing conditions the important cucurbitaceous vegetable grown in The research was carried out from 2012 to 2014 in India. The crop is cultivated over an area of 80990 ha the experimental farm of the Department of in India with an annual production of 830450 tonnes Vegetable Crops, Tamil Nadu Agricultural University, and the productivity of 10.25 t/ hectare1. The main Coimbatore, India at 110 N latitude, 770 E longitudes problem with bitter gourd production in India is 2 and an altitude of 426.26 m above mean sea level. root knot nematode and Fusarium wilt . Several studies on effects of grafting on plant growth and Rootstocks and scions fruiting characteristics under normal as well as The two bitter gourd cultivars (Palee F1 and CO 1) stress conditions have been conducted in cucurbits. were selected, out of which one is a private hybrid viz., However to our knowledge, there is no published Palee F1 from East West Seeds, Philippines which is scientific research on the effects of grafting on suitable for early and long duration harvest and widely increasing resistance to soil-borne diseases as well as cultivated F1 hybrid in Tamil Nadu, India. Fruits are improving yield and yield related characters in bitter medium long with moderate, but rather thick spines gourd in India. Therefore, the hypothesis of this study which result in less damage during transport. CO 1, a was to determine the effects of grafting technique in variety from Tamil Nadu Agricultural University. bitter gourd (Momordica charantia) cv. Palee F1 and Fruits are dark green, 20-25 cm long, susceptible to CO 1 with pumpkin and sponge gourd as rootstocks root knot nematode and Fusarium wilt. The most and ascertain the plant growth, yield and quality. commonly used rootstocks for bitter gourd are Luffa (Luffa spp.), fig leaf gourd (Cucurbita ficifolia) and pumpkin (Cucurbita moschata) showing good —————— 3 *Author for Correspondence vigour and compatibility . In addition pumpkin exhibit E-mail: [email protected] resistant reaction to Fusarium wilt and improves plant TAMILSELVI & PUGALENDHI: STUDIES ON EFFECT OF GRAFTING TECHNIQUE ON GROWTH OF BITTER GOURD 655 vigour; tolerant to squash borer, root knot nematode, The grafting was done under green house during low temperature and drought through vigorous root morning and evening hours. The grafted plants were system. Whereas Luffa is highly compatible, better transferred immediately to the mist chamber where rootstock for earliness, fruit yields, resistant to Fusarium optimum RH (>95per cent), temperature (25-30° C) wilt and tolerance to heat and flooding and widely used and dark condition prevailed for five to seven days. for summer production. The rootstocks Kumatikai After acclimatization, the plants were then transferred (Citrullus colocynthis) and African horned cucumber to shade house on 7th day after grafting. Stock growth (Cucumis met uliferous) found to be highly resistant to and cotyledonary leaves are removed before planting drought, Fusarium wilt and tolerant to root knot in field. Graft compatibility was assessed in terms of nematode. percent survival of grafted plants at 15 days after Fig leaf gourd (Cucurbita ficifolia) and Zucchini grafting (DAG) squash (Cucurbita pepo) were highly tolerant to low temperature and resistant to Fusarium wilt4,5. Based on Preliminary evaluation of graft combinations under field these reports the following rootstocks were selected for condition bitter gourd grafting. The rootstocks viz., Mithipakal About four graft combinations viz., Palee F1 grafted (Momordica charantia var. muricata), teasle gourd onto pumpkin (C. moschata) rootstock, CO 1 grafted (Momordica dioica), athalakai (Momordica cymbalaria), onto pumpkin (C. moschata) rootstock, Palee F1 kumatikai (Citrullus colocynthis), African horned grafted onto sponge gourd (L. cylindrica) rootstock and cucumber (Cucumis met uliferous), fig leaf gourd CO 1 grafted onto sponge gourd (L. cylindrica) (Cucurbita ficifolia), pumpkin (Cucurbita moschata), rootstock recorded maximum success percentage when zucchini squash (Cucurbita pepo), bottle gourd compared to other graft combinations. These graft (Lagenaria siceraria), ash gourd (Benincasa hispida), combinations and thirty days old seedlings of scions ridge gourd (Luffa acutangula) and sponge gourd (Palee F1 and CO 1) were transplanted in the beds at 2 (Luffa cylindrica) were collected from different x 1 m apart under pandal system. The experimental parts of Tamil Nadu, India and grafted with the design consists of randomized block design (RBD) aforementioned two bitter gourd scions. with four replication. There were 25 plants per treatment per replication. Plants were trained over the Screening of rootstocks and scions against meloidogyne pandal after the development of lateral branches and incognita under in vitro Pot culture experiment was conducted under these were vertically supported by jute threads 10 cm glasshouse condition at the Department of Nematology, from the ground level and tied to iron wires distributed TNAU, Coimbatore. Thirty days old healthy seedlings along each row. The shoots arised below the pandal of rootstocks and scions were planted in earthen was eliminated. Recommended package of practices of TNAU was followed to grow a successful crop of pots containing 2.5 kilogramme of sterilized pot mixture 7 (Red soil: Sand: FYM in 2:2:1 ratio).Each pot was bitter gourd . During the growing season, the following inoculated with second stage juvenile of M. incognita vegetative and yield traits were recorded for each plant; vine length (cm), number of primary branches, days to at the rate of two juvenile (J2)/g of soil.The nematode first female flower appearance, node number to female inoculum (J2) was placed in 2 cm depth near to the rhizosphere and covered with sterile sand. The roots of flower appearance, sex ratio, fruit number per vine, these plants were harvested 45 days after inoculation fruit weight (g), fruit length (cm) and girth (cm), flesh and washed free of soil. The observation viz., Number thickness (cm), fruit yield per vine (kg), total number of galls, number of egg masses, number of root knot of harvest and crop duration. The quality parameters nematode females and root knot index were recorded. viz., total soluble solids of fruit samples at vegetable The root knot nematode index (RKI) was calculated by maturity were estimated using hand refractometer and using standard method6. expressed in ºBrix; Ascorbic acid of fruit was estimated by volumetric method and expressed as mg per Grafting 100 g8. Total chlorophyll content of the leaves was Grafting was performed in 25-30 days old seedlings. estimated and expressed as mg per 100 gram9. All the The grafting method adopted in this experiment was statistical analysis was done using AGRES Version side grafting. The best time for side grafting is when 7.01 software. The test of significance was worked out at the rootstock and scion stems have the same diameter. P = 0.05 level of probability10. 656 J SCI IND RES VOL 76 OCTOBER 2017 Results and Discussion cucurbitaceous species against M. incognita (Table 1). All the rootstocks and scions developed The results revealed that kumatikai (C. colocynthis), characteristic galls caused by M.incognita. Significant African horned cucumber (C. metuliferus) and differences were noticed among the rootstocks for pumpkin (C. moschata) rootstocks had the least count number of galls per five gram root, number of egg of root knot index of 2, attaining a reaction category of masses per five gram root and number of females per ‘resistant’ (R), whereas mithipakal (M.charantia var. five gram of root (Table 1). Kumatikai (C. colocynthis) muricata) and sponge gourd (L. cylindrica) exhibited (3.11, 1.42 and 2.34) followed by African horned higher number of galls and recorded a root knot index cucumber (C. metuliferus) (4.20, 1.54 and 2.56) and of 3 and the corresponding reaction category of pumpkin(C. moschata) (8.93, 3.74, 5.56) recorded the ‘moderately resistant’ (MR). The gall index of 4 was lowest number of galls, number of egg masses and observed in ridge gourd (L.