Effect of Temperature on Development and Reproduction of Aphis Gossypii(Hom.,Aphididae)

The development,death rate and reproduction of the Aphis Gossypii(Hom., Aphididae) were evaluated on detached cotton leaves at six high constant temperature (26℃,28℃,30℃,32℃,34℃, 36℃) in laboratory. The developmental periods of the immature stage ranged from 5.9 days at 26℃ to 4.4 days at 34℃. A constant temperature of 36℃ was lethal to the immature stage of Aphis Gossypii and death rate was up to 99% in four days. The death rate was estimated to be 17.5%,25.0%,25.5%,22.6% and 22.0% at 26℃,28℃,30℃,32℃,34℃. The age-specific fecundity and net reproductive number were at peak numbers at 28℃ with numbers of 14.0 and 53.0. The intrinsic rate of increase was estimated to be 0.304,0.398,0.385,0.245 and 0.124 at five temperatures. The optimum temperature for development was 29.0℃ and lethal temperature for development of cotton Aphid was 35.5℃. The optimum temperature for reproduction was 28.8℃ and lethal temperature for fecundity of cotton Aphid was 34.9 ℃ based on fitting model. Summer aphid appeared relatively great reproduction from 28℃ to 30℃, and seriously damaged to cotton growth.