Temperature effects on development and fecundity of Brachmia macroscopa (Lepidoptera: Gelechiidae)

Abstract

The current study investigated the impacts of temperature on the development and reproductivity of the sweet potato leaf folder, Brachmia macroscopa (Lepidoptera: Gelechiidae), in sweet potato leaves under laboratory conditions. We determined developmental time of B. macroscopa larval, pupal, and pre-adult stage at different temperatures. Male and female longevity, male and female lifespan, mortality of immature stages, oviposition period of B. macroscopa were also investigated under six constant temperatures (21°C, 24°C, 27°C, 30°C, 33°C, 36°C), based on age-stage, two-sex life tables. The results revealed that eggs in 36°C were unable to hatch. At temperatures between 21°C -33°C, the duration of the pre-adult period, as well as the adult lifespan both for males and females, were shortened by increasing temperatures. The lowest larval mortality rate (15.33%) occurred at 27°C. The age-stage-specific fecundity rates with the greatest number were, in order, 30°C, 27°C, 21°C, 24°C and 33°C. The results show that B. macroscopa population levels could reach highest at the temperature of 27℃.