Laboratory studies on the effect of temperature and humidity on the life table of the whitefly,Aleurotuberculatus takahashi David & Subramaniam (Hom., Aleyrodidae) from southeastern China

The present paper deals with developmental duration, emergence, longevity and fecundity ofAleurotuberculatus takabashi David & Subramaniam at different temperatures and humidity levels. The developmental time from egg to adult was 81.8, 56.9, 39.6, 29.9, 20.6 days at 15±1, 20±1, 25±1, 30±1, 35±1°C under constant relative humidity (RH) of 70±5%, respectively. At 25±1°C, the total developmental time was slightly affected by humidity, ranging from 46.4 days at 40±5% RH to 39.2 days at 90±5% RH. The developmental threshold and the thermal constant for the stage from egg to adult were 10.1°C and 542.8 day-degrees. It was estimated that the whitefly has about 10 generations a year in Fuzhou region in southeastern China. Lowest mortality rates of 12.4% for the egg, 6.8% for the nymph and 3.1% for the puparium were obtained at 15±1°C, while they were highest with 92.1% for the egg, 48.2% for the nymph and 36.3% for the puparium at 35±1°C. The mortality rates were slightly affected by humidity, ranging from 17.6% at 40±5% RH to 27.9% at 90±5% RH for the egg, 11.2% at 40±5% RH to 19.6% at 90±5% RH for the nymph, and 6.4% at 40±5% RH to 11.6% at 90±5% RH for the puparium. The emergence rate of adults decreased as temperature increased, ranging from 89.1% at 15±1°C to 21.5% at 35±1°C, so did the longevity of adults, ranging from 9.6 days at 15±1°C to 2.9 days at 35±1°C. The number of eggs per female was significantly affected by temperature (P.01), valuing 29.4 eggs per female at 15±1°C, 36.7 at 20±1°C, 52.4 at 25±1°C, 42.9 at 30±1°C, and 6.1 at 35±1°C. The optimal temperature for reproduction was about 25°C.