Impact of numerous larval diets on biology of pink bollworm Pectinophora gossypiella (Lepidoptera: Gelechiidae) under laboratory conditions

Abstract

Abstract Pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) has become a potential pest of cotton by causing substantial yield losses around the world including Pakistan. As a limited past research investigations on dietary aspect of P. gossypiella are available, the present study was conducted. A number of biological aspects of P. gossypiella were studied by rearing on different larval diets that were prepared using indigenous elements. The standard/laboratory diet comprised of wheat germ-meal 34.5, casein 30.0, agar-agar 20.0, sucrose 10.0, brewer’s yeast 5.0, α-cellulose 1.0, potassium-sorbate1.5, niplagin 0.5, decavitamin 0.01, choline-chloride 0.06, maize-oil 3.30, honey 2.0, and water 730.0 g/ml/kg. Alternative natural diets cotton, okra seed sprouts, cotton bolls and okra fruit was also included in the study. Among artificial diets, larval development was completed in 19.68±0.05 days with weight of 20.18±0.20 mg at fourth instar fed on cottonseed meal-based diet instead of wheat germ-meal based diet. On same diet, 84.00±4.00%, 17.24±0.03 mg and 7.76±0.06 days was recorded as pupation period, pupal weight and pupal duration, respectively. Adult emergence, 76.00±1.00% was recorded from pupae collected larvae those raised on cottonseed meal based diet. These adults (males and females) lived for 40.25±0.10 and 44.34±0.11 days, respectively. Female moths deposited 21.28±0.04 eggs/day with 65.78±0.14% viability. The larval mortality was 37.20±1.36% was recorded while remaining (62.80±1.36%) larval population successfully pupated. Mal-pupation 12.00±1.41% was also documented. This research is of novel nature as it provides concise, objective oriented and practical interventions for economic and successful rearing of P. gossypiella.