تاثیر دماهای مختلف روی پراسنجه‌های جمعیت نگاری دو جمعیت ساقه‌خوار ذرت Sesamia cretica Led. جمع‌آوری شده از ورامین و ری

Pink stem borer, Sesamia cretica Led., is considered as the main pest insect of maize and sugarcane in the fields throughout the world and in Iran. Reproduction and life table parameters of two populations of the pink stem borer collected from Varamin and Rey were studied at 10 constant temperatures (12, 15, 20, 25, 27, 30, 32, 34, 35 and 36 (±1)°C, 50±10% RH and a photoperiod of 0:24 (L:D) h for the larval stage and 16:8 (L:D) h for the other stages). All data were analyzed based on age-stage, two-sex life table theory. At 12°C no eggs hatched and at 15, 35 and 36°C only the incubation period completed, with a significant difference between the studied populations. Male and female longevity was inversely related to temperature so that, with increasing temperature their longevity decreased. The oviposition period was significantly different at these six temperatures and decreased with increasing temperature, only at 20 and 34°C was a significant difference between the studied populations. The intrinsic rate of increase at temperatures 20, 25, 27, 30, 32 and 34°C was 0.0262, 0.0237, 0.0343, 0.0386, 0.0119 and -0.0216 day-1 respectively for Varamin population and 0.0212, 0.0234, 0.0349, 0.0258, 0.0129 and -0.0051 day-1 respectively for Rey population. The intrinsic rate of increase and finite rate of increase (1.0349 and 1.0355 day-1 for Varamin and Rey populations, respectively) were greatest at 27°C. At 30°C all parameters of the life table showed a significant difference between the two populations. As well as, the intrinsic rate of increase, finite rate of increase and mean generation time were significantly different between two populations at 20 and 34°C. Considering the results obtained here, temperature is one of the most important factors affecting life table parameters of pink stem borer and among populations their values would be different significantly.