Morphological and Biochemical Factors of Resistance in Eggplants against Leucinodes orbonalis (Lepidoptera: Pyralididae)

Abstract

Ten genotypes ofeggplants viz, one resistant (HLB-12), two susceptible (NDB-28-2 and BB-46), five highly susceptible (BB-102, APAU-4, Sel-4, BB-16-3 and CH-157-16-4) to shoot and fruit borer, Leucinodes orbonalis (Guenee 1854) and two cultivated varieties (Hisar Pragati and BR-112) were included to study the influence of morphological and biochemical factors on the infestation of this insect pest. The resistant genotype HLB-12 exhibited significantly (p≤0.05) less fruit damage (29%) by shoot and fruit borer than the highly susceptible genotypes (42.00 to 61.50%). Correlation of thickness of pericarp (r=0.80) and mesocarp (r=0.70) with resistance were positive and significant, while the effect of fruit length was non-significant with the incidence of shoot and fruit borer. The genotypes having compact seed rings with closely arranged seeds in mesocarp of fruits were less damaged by the borer. Among phytochemicals in fruits, moisture (r=0.84), crude protein (r=0.68) and nitrogen (r=0.69) contents manifested positive and significant correlations while total sugars (r= -0.67), fibre (r= -0.76), tannin (r= -0.85) and phenol (r= -0.80) contents showed significantly negative correlations with per cent fruit infestation by shoot and fruit borer. Among mineral constituents, potassium and manganese showed significantly negative effects on the incidence of shoot and fruit borer.