Effect of temperature on the life table parameters and high-temperature lethality of Tyrophagus putrescentiae

The effects of five constant temperatures (16, 20, 24, 28, and 32 °C) on the development and reproduction of a serious stored products pest, Tyrophagus putrescentiae, fed on wheat bran were evaluated in the laboratory at 75% relative humidity. In addition, the efficacy of high temperatures (lethal temperatures) ranging from 39 to 49°C on the mortality of mobile stages of T. putrescentiae was investigated. The development time of different stages was decreased with increasing temperature, and total immature stages varied from 55.37 to 11.46 days. The pre-oviposition, oviposition, and post-oviposition periods, and female longevity all decreased with the temperature increasing. The longest oviposition period was 46.12 days at 16 °C. The female ratio increased from 52.4 to 68.8%. With the temperature. From 16 to 32 °C, the mean eggs deposited per day were 0.544, 0.994, 2.055, 3.034, and 1.421, respectively. The maximum fecundity (87.69 eggs per female) and the highest intrinsic rate of increase (rm) (0.194) were at 28 °C. In all mobile stages, mortality increased with the increase in temperature and exposure time. When temperatures ranged from 39.0 to 49.0 °C, the half-lethal time (LT50) of adult T. putrescentiae was 347.47, 124.38, 60.01, 33.66, 22.06, and 13.49 min, respectively, and it was shortened by half when the temperature was increased by 2 °C. The larvae were more sensitive to high temperatures than in other stages. Interestingly, the LT50 of adults was almost twice as LT50 of larvae under each temperature. The study suggests that temperature significantly affects the development, survival, and reproduction of T. putrescentiae, and heat treatment is an effective method to control this pest.