Antixenotic resistance traits of muskmelon cucumis melo( l.) against fruit fly (Bactrocera cucurbitae (coquillett)) in arid region of India

Abstract

Plant genotypes possess different antixenotic properties, which resultantly induce in them different mechanisms of resistance. Various antixenotic traits including length of pubescence, fruit toughness, rind thickness, flesh thickness, days to first harvest and fruit diameter were studied on eleven genotypes of muskmelon ( L.) in relation to resistance against under field conditions in the hot arid region of India. Significant differences were observed in the tested genotypes for fruit infestation and larval density per fruit. AHMM/BR-1, RM-50 and AHMM/BR-8 were resistant; MHY-5, Durgapura Madhu and Pusa Sarabati moderately resistant; AHMM/BR-13, Pusa Madhuras and Arka Jeet susceptible; while, Arka Rajhans and GMM-3 were the highly susceptible genotypes to fruit fly infestation. Spositive correlation (r = 0.97) was observed between per cent fruit infestation and larval density per fruit. The percent fruit infestation and larval density had significant positive correlations with fruit diameter and days to first harvest and negative correlation with fruit toughness, rind thickness, flesh thickness and length of ovary pubescence. Maximum variation in fruit infestation and larval density was explained by length of ovary pubescence (63.3 and 45.7% respectively) followed by fruit toughness (6.7 and 13.7% respectively) and fruit diameter (8.6 and 10.5% respectively).