Biotic Potential and Life Table of Helicoverpa armigera Hubner on Pigeonpea Pods

Abstract

Studies on the innate capacity for increase in number of Helicoverpa armigera (Hubner) were carried out at a constant temperature of 26 ± 1°C on pigeonpea pod in 1994. The number that survived from egg to adult was 76 individuals. Under a limited space and sufficient food supply, the population of H. armigera increased with an infinitesimal rate (rm) of 0.1365 and finite rate (λ) 1.147 females per female per day. The net reproductive rate (Ro) was 427.94. A generation was completed in 46.06 days. The population was able to multiply 427.94 times per generation on pigeonpea pods. The population on reaching a stable age distribution comprised approximately 99 per cent of immature stages. The expectation of further life at the age interval of 35 to 50 days was reduced to 5.13 days from 16.35 days in the beginning.