A Comparative Analysis of Age-Stage Two Sex Life Tables in Distinct Forms of Callosobruchus maculatus (F.): Insights into Population Dynamics and Reproductive Strategies

Abstract

Callosobruchus maculatus, the bean weevil, is a fascinating insect that showcases remarkable adaptations for survival. Found in tropical and subtropical regions, it has become a global pest due to its adaptability and hitchhiking capabilities, causing substantial grain losses. This small beetle, part of the Chrysomelidae family, serves as a valuable model organism in entomology and agricultural research. One of the key aspects of Callosobruchus maculatus that captures the attention of scientists is its dichotomy between active and inactive forms. These two forms represent distinct survival strategies employed by the beetle to navigate its ever-changing environment. The present study provides a comprehensive overview of the study on Callosobruchus maculatus, highlighting the two distinct forms of the species, their adaptations, and the significance of understanding their lifetable parameters. It emphasizes the ecological, practical, and research-oriented implications of this study, ranging from ecological insights to pest management strategies and the optimization of mass multiplication protocols. These forms exhibited notable differences in various life history parameters and survival characteristics. Flightless-inactive females had longer preoviposition and oviposition period and laid a significantly higher average of eggs per female with higher reproduction potential. Female fecundity (eggs/female) was much lower in the flight-active form (18.6) than in the flightless-inactive form (84.10) and maintained constant survival rate. Life expectancy values were generally lower for the flightless-inactive form compared to the flight-active form across different stages and sexes. Both males and females in the flight-active form exhibited a consistent and relatively high life expectancy, with a 100% chance of survival throughout all age intervals. Overall, these findings provide a comprehensive understanding of the differences in life history traits, reproductive strategies, and survival patterns between the flight-active and flightless-inactive forms of Callosobruchus beetles in a controlled laboratory environment.