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Abstract

Life history parameters of apterous viviparous Myzus persicae reared on qing-geng-cai were measured at constant temperatures of 15, 20, 25 and 30°C under a 16L–8D photoperiod. Mean developmental times from 1st instar to adult emergence decreased as the temperature increased. Survival rates were over 90% at all temperatures and showed no significant difference between each temperature. The lower developmental threshold and total effective temperature were calculated as 5.6°C and 113.1 degree-days. The adult fertility and longevity reached a maximum at 20°C, but the intrinsic rate of population increase was highest as 0.420 at 25°C.