Short-Term Temperature Stress Modulates Fitness Traits in Bactrocera zonata, through Negative Impact on Larval Stage

The frequency and magnitude of climate extremes, especially temperature extremes (TE), are increasing, which are exposing insect populations. However, insect responses to TE are poorly understood. In this study, we investigated the impact of high-temperature (HT: 38 °C) and low-temperature (LT: 3 °C) stresses on demographic parameters and population projections of the peach fruit fly, Bactrocera zonata, a destructive pest of fruits and vegetables. Results show that the larval developmental stage was significantly increased by HT (8.30 d) and LT (8.10 d) compared with control (7.02 d). The preadult stage in the HT and LT stressed flies were 18.56 d and 18.40 d, respectively compared with control (17.37 d). Mean longevities of both males and females were also substantially prolonged in HT and LT treatments. Compared with control, the total pre-oviposition period (TPOP) and oviposition days of B. zonata were significantly increased in both stress conditions. Furthermore, female fecundity of flies significantly increased in both HT and LT (705.48 and 698.38 respectively) treatments compared with control (578.35). These findings show that temperature stresses in the larval stage delayed the larval development and increase the reproduction and life span of B. zonata. The temperature induces alteration in life-history traits that might have significant agricultural impacts on the control strategies for this key pest.