Influence of Insecticides on Food Consumption and Utilization Behaviour of Different Leucinodes orbonalis Populations from Punjab

Leucinodes orbonalis Guenee is a monophagous and serious pest causing high damage in the brinjal crop The effect of the different insecticides viz. emamectin benzoate 5 SG, chlorantraniliprole 18.5 SC, deltamethrin 2.8 EC, spinosad 45 SC, fenvalerate 20 EC, cypermethrin 25 EC on food consumption and utilization in different L. orbonalis larval populations of Punjab were observed in a laboratory. Emamectin benzoate showed the most potent effect on the feeding of L. orbonalis larvae and lowest relative consumption rate (RCR), relative growth rate (RGR), the efficiency of conversion of ingested food to body substance (ECI) and efficiency of conversion of digested food to body substance (ECD) with highest approximate digestibility (AD). The nutritional indices value except AD was higher for L. orbonalis larvae fed on untreated food followed by deltamethrin, fenvalerate, chlorantraniliprole, cypermethrin, spinosad and emamectin benzoate treated food. The RCR, RGR, ECI, ECD were maximum for larval populations of the Amritsar region followed by Kapurthala, Malerkotla, Ludhiana and susceptible populations. The approximate digestibility (AD) was higher for larvae of the susceptible population followed by Ludhiana, Malerkotla, Kapurthala and Amritsar populations of L. orbonalis. The findings of present study would be helpful in designing management strategies for L. orbonalis.