Rearing of Spodoptera litura (Fabricius) on Different Artificial Diets and its Parasitization with Trichogramma chilonis (Ishii)

Abstract

Studies on rearing of Spodoptera litura (Fabricius) on different artificial diets i.e., bean based diet (Diet-1) and gram based diet (Diet-2) and its parasitism with Trichogramma chilonis (Ishii) were conducted under controlled laboratory conditions of 27±2°C, 65±5% RH and 14:10 L:D during 2013. The results showed that feeding the 1 st , 2 nd and 3 rd generations of the immature stage of S. litura on diet-2 resulted in highest % survival rates among all the parameters of immature stages of S. litura, lower total larval duration (15.8 days as against 17.2 days of control) and total duration from egg to adult stage (29.6 days as against 31.9 days for diet-1). The mature adult stage of S. litura showed almost same trend of better performance of S. litura fed on diet-2 in terms of higher oviposition period 5.7 days and higher female fecundity (total number of eggs 1612.3) compared with the oviposition period 5.2 days and female fecundity (total number of eggs 1541.86) recorded for diet-1. No significant difference was observed among the diets in the % parasitism rate of S. litura by T. chilonis. Increased trend of parasitism coincided with the increased time of exposure. Highest parasitism rate of 91.1% and 89.5 % was observed in the egg cards exposed to T. chilonis for 24 h in Diet-2 and Diet-1, respectively, while after 16 h exposure, 90 and 88.6 % was recorded for Diet-2 and Diet- 1, respectively. Diet-2 was found to be better compared with Diet-1 for rearing of S. litura. Comparatively higher parasitism was observed in 16 and 24 h of exposure time of egg cards of S. litura to T. chilonis.