Abstract: 【Aim】 As the global climate becomes warmer, the frequencies of transient extremely high temperature have gradually increased. This study aims to understand the thermal adaptation of Athetis lepigone larvae at high temperature. 【Methods】 The survival rate, larval duration, pupation rate, emergence rate, female longevity, fecundity and egg hatching rate of A. lepigone reared at the constant temperature 26℃ and treated with heat stress at 35, 38, and 41℃ for 0.5, 1, 2, 4, and 6 h, respectively, in different larval stages were observed and compared with the untreated control reared at the constant temperature 26℃. 【Results】 Both temperature and duration of exposure to high temperature significantly affected the survival rate and larval duration of A. lepigone. No significant differences were observed in pupation rate, emergence rate, female longevity and fecundity of adults, and egg hatching rate between the heat stress groups and the control. The survival rate of larvae tended to drop and the larval duration prolonged with the increase of temperature and duration of exposure. The 18-day-old larvae were the most sensitive to high temperature. After the larvae were exposed to 38℃ and 41℃ for 6 h, their survival rates were 58.3% and 17.7%, respectively, significantly lower than that of the control, and the larval duration was 25.5 d and 29.2 d, respectively, significantly longer than that of the control.  【Conclusion】 Short-term exposure to high temperature in the larval stage of A. lepigone only affects its larval survival rate and duration, but has no effect on its pupal and adult development and adult fecundity.

Key words: Athetis lepigone, temperature, transient high temperature, growth and development, survival, fecundity