Life Table Parameters and Age-Specific Mortality of Helicoverpa armigera (Lepidoptera: Noctuidae) on Different Host Plants
Keywords:
Helicoverpa Armigera, Life Table Analysis, Host Plants, Age-Specific Mortality, Population Dynamics, Pest ManagementAbstract
Understanding the population dynamics and survival patterns of insect pests on different host plants is essential for developing effective pest management strategies in agricultural ecosystems. The present study evaluated the life table parameters and age-specific mortality of Helicoverpa armigera (Lepidoptera: Noctuidae) reared on different host plants under controlled laboratory conditions. Larvae were maintained on selected economically important host crops, and observations were recorded on developmental duration, survival rate, fecundity, adult longevity, and reproductive potential. Age-stage, two-sex life table analysis was employed to estimate population growth parameters including intrinsic rate of increase, net reproductive rate, finite rate of increase, and mean generation time. Significant variations were observed in biological performance and demographic characteristics of H. armigera among the tested host plants. Certain host plants supported faster larval development, higher survival, and increased fecundity, resulting in greater population growth potential. In contrast, less suitable host plants caused prolonged developmental periods and elevated mortality during immature stages. Age-specific mortality analysis revealed that early larval instars were more vulnerable to adverse nutritional effects and environmental stress compared to later stages. Differences in nutritional composition and defensive compounds among host plants significantly influenced pest survival and reproductive fitness. The findings demonstrate the strong influence of host plant suitability on the population ecology of H. armigera and provide valuable information for predicting pest outbreaks in cropping systems. The study contributes to the development of integrated pest management strategies through the identification of less favorable host plants and improved understanding of pest population dynamics.
