PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

The present study was conducted at the AICRP on Vegetable Crops, Department of Horticulture, MPKV, Rahuri, to evaluate graft compatibility of muskmelon hybrids on different cucurbit rootstocks. Three commercial muskmelon hybrids (S₁, S₂, S₃) were grafted onto six rootstocks, pumpkin (Arka Chandan, Arka Suryamukhi), bottle gourd (Arka Bahar, Samrat), and sponge gourd (Phule Komal, Phule Prajakta). Parameters studied included rind thickness, biochemical traits (βeta-carotene, ascorbic acid, TSS), and pest–disease incidence. The highest TSS was recorded in R₂S₂ (13.50 °Brix) during kharif and R₁S₂ (14.50 °Brix) in summer. Ascorbic acid content was maximum in R₅S₃ (35.53 and 38.73 mg/100 g), while the highest βeta-carotene content occurred in R₁S₂ (0.187 and 0.213 mg/100 g) across seasons. Maximum rind thickness was observed in R₅S₁ (0.44 cm) during kharif and R₅S₂ (0.54 cm) in summer. The lowest downy mildew incidence (7.48%) was in R₆S₂, and the least powdery mildew (6.56%) in R₆S₁ during kharif. The lowest leaf miner infestation (7.65% and 5.24%) was noted in R₂S₃ during both seasons. The main goal of this study is to assess the effectiveness and compatibility of grafting muskmelon hybrids (S₁, S₂, S₃) onto several cucurbit rootstocks in terms of resistance to main diseases and pests and fruit quality (rind thickness, βeta-carotene, ascorbic acid, and TSS).  Fruit quality and resistance to pests and diseases were greatly impacted by graft combinations. R₅S₃ had the most ascorbic acid, R₅S₂ had a thicker rind, and R₁S₂ and R₂S₂ had higher levels of TSS and βeta-carotene. The effectiveness of rootstocks R₆ (Phule Prajakta) and R₂ (Arka Suryamukhi) in lowering disease and pest incidence suggests that they may be suitable for muskmelon grafting during both the summer and kharif seasons.