Effects of Temperature on Development of Myzus Persicae (Sulzer)

The effects of temperature on development of Myzus persicae (Sulzer) was investigated at five constant temperature 17, 20, 23, 26 and 29± 1 °C, 65± 5 % RH, and a photoperiod of 16:8 (L:D) hr fed on cabbage (Brassicae olerasia var. capitata) under laboratory condition using the age-stage, two-sex lifetable approach. The intrinsic rate of increase (r) of this aphid was highest at 29°C (0.3212 d^-1) and lowest at 17°C (0.0.2157 d^-1). The developmental rate of nymphs at different temperatures fit the linear equation, y= 0.005x-0.001 with a coefficient of determination (R²) of 0.98. The thermal summation of the pre-adult, the female, and the total life stages (from birth to death) was 194.6, 241.8 and 430.2 DD, respectively. The developmental threshold of the pre-adult, the female, and the total life stage was 0.29, 10.6, and 5.29°C, respectively. The mean generation time was 18 d at 17°C, which declined to 10.2 d at 29°C. The net reproduction rate (R₀) was 26.6 offspring/individual at 29°C, and it was considerably lower than the rates obtained at other temperatures. The highest net reproductive rate was obtained at 20°C (R₀= 54.2 offspring/individual). In the absence of other limiting factors, populations of M. persicae would be expected to increase faster if introduced into environments having temperature ranging between 23 and 26°C.