Effects of Chilling of Bemisia argentifolii (Homoptera: Aleyrodidae) Infesting Cabbage

Cold temperatures affected the biology of Bemisia argentifolii Bellows and Perring on cabbage both directly and indirectly. Continuous chilling of 0°C and 4°C significantly increased mortality of adults and eggs. Variable daily chilling of 0°C for 6 h and then greenhouse conditions for the remainder of the day increased adult mortality but did not affect egg mortality for the 10 days of exposure. Prior plant exposure to 0°C resulted in reduced adult B. argentifolii preference and increased adult mortality. Previous 0°C and 4°C plant exposure also had an impact on within plant distribution of adults and eggs. On nonchilled and recently chilled plants, adults and eggs were found on the youngest (highest) leaves. On plants chilled at 0°C and 4°C three and five days before infestation, adults and eggs were found on lower leaves. Lower immature mortality was recorded on the nonchilled plants than on the chilled plants.