Effect of temperature on reproduction, development, and phenotypic plasticity of Drosophila suzukii in Brazil

Temperature is a determining factor for the development and establishment potential of insect pests. The present study describes the impact of temperature (13, 18, 23, 25, 28, 30, and 33 °C) on the life cycle parameters and phenotypic plasticity of South American populations of Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) in the laboratory. Secondary objectives were to determine the lower thermal threshold and thermal constant to estimate the number of annual generations of the insect in small‐fruit‐producing regions in Brazil. The highest egg‐to‐adult survival was recorded at 23 and 25 °C. At 30 and 33 °C, no emergence of D. suzukii was observed. The egg‐to‐adult development time was shortest at 25 and 28 °C (ca. 10 days). The net reproductive rate (R0), and the intrinsic rate of population increase (rm) were highest at 23 and 25 °C. In contrast, temperatures of 13 and 28 °C generated largest and smallest body sizes, respectively, and caused reductions of 99 and 93% in R0. The estimated lower thermal threshold was 7.8 °C for egg‐to‐adult survival. The estimated thermal constant was 185.8 degree days, and the estimated annual number of generations of D. suzukii ranged from 17.1 in cold regions to 27.2 in warm regions. The results of the present study are important for understanding D. suzukii occurrence in the field, contributing to more informed and precise pest management. The effect of temperature on the biology, body size, and thermal requirements of a South American population of spotted wing drosophila, Drosophila suzukii (Diptera: Drosophilidae), was evaluated in the laboratory. Egg‐to‐adult survival, net reproductive rate (R0), and the intrinsic rate of population increase (rm) were highest at 23 and 25 °C. This first study to address the effects of temperature on biological aspects of South American populations of D. suzukii will assist in the development of pest management and breeding techniques.