Prey Consumption and Development of Coccinella septempunctata Fed on Aphis fabae Under Variable Temperature Regimes

Abstract

Temperature is a critical environmental factor influencing the feeding behavior, development, and biological efficiency of predatory insects used in biological control programs. The present study evaluated the prey consumption and developmental performance of Coccinella septempunctata fed on Aphis fabae under different temperature regimes under controlled laboratory conditions. Various developmental stages of the predator were reared at selected temperature levels, and observations were recorded on prey consumption rate, larval duration, pupation, adult emergence, survival, and reproductive performance. Results indicated that temperature significantly affected both feeding efficiency and developmental parameters of C. septempunctata. Increased prey consumption was observed with rising temperatures up to an optimum level, beyond which feeding activity and survival declined. Larval and pupal developmental periods were considerably shorter at moderate temperatures, while extreme temperature conditions negatively affected growth and adult emergence. The highest predation efficiency and survival rates were recorded under favorable thermal conditions, indicating improved biological performance of the predator. Age-specific prey consumption analysis revealed that later larval instars consumed substantially higher numbers of aphids compared to earlier stages. Temperature-induced variations in predator development and feeding behavior demonstrated the strong influence of environmental conditions on predator–prey interactions. The findings highlight the potential of C. septempunctata as an effective biological control agent against A. fabae under suitable temperature conditions. The study provides valuable information for optimizing mass rearing and field release strategies of predatory coccinellids in integrated pest management programs targeting aphid infestations in agricultural ecosystems.