Predatory Efficiency and Prey Preference of Serangium parcesetosum (Coleoptera: Coccinellidae) on Bemisia tabaci Nymphs

Abstract

Predatory efficiency and prey preference of Serangium parcesetosum (Coleoptera: Coccinellidae) were evaluated against Bemisia tabaci nymphs to assess its potential as a biological control agent under controlled laboratory conditions. Experiments were conducted across varying prey densities to determine consumption rate, functional response type, and feeding preference among different developmental stages of the whitefly. Results indicated that both larval and adult stages of S. parcesetosum actively preyed upon B. tabaci nymphs, with larvae exhibiting higher per capita consumption rates compared to adults. Predation increased with prey density up to a saturation point, beyond which handling time limited further consumption, indicating a Type II functional response. Early instar nymphs were preferred over later instars due to their reduced mobility and softer cuticle, resulting in higher feeding efficiency. The predator demonstrated strong numerical response potential under high prey availability, suggesting its suitability for rapid suppression of whitefly outbreaks. Temperature influenced predation rates, with optimal feeding observed under moderately warm conditions typical of greenhouse and field vegetable systems. Continuous prey availability supported sustained reproduction and population buildup of the predator. The study highlights the effectiveness of S. parcesetosum as a specialized whitefly predator and its potential integration into biological control programs targeting B. tabaci in protected and open-field cropping systems. These findings support the development of augmentative release strategies and conservation-based management approaches to enhance natural suppression of whitefly populations and reduce reliance on chemical insecticides in sustainable pest management programs.