Factors Affecting Egg Hatch, Development, and Survival of Bemisia argentifolii (Homoptera: Aleyrodidae) Reared on an Artificial Feeding System

Improvements in the way Bemisia argentifolii Bellows & Perring is managed have led to reduced whitefly populations in the southwest United States. However, the potential of the silverleaf whitefly to develop new biotypes, as well as its apparently increasing role in virus transmission, makes it a persistent threat in many parts of the world. Characteristics such as biotype formation and vector competency are at least partially explained by the host range of B. argentifolii. Consequently, a better understanding of the factors that play a role in the host acceptance process and subsequent development of this pest could lead to novel control strategies. Here we used a newly developed artificial feeding system that consists of a polycarbonate chamber, equipped with a Teflon membrane, and filled with a sterilized artificial diet, to determine how biotic and abiotic factors influenced egg hatch, crawler establishment, and development of B. argentifolii. Egg age significantly influenced hatch rates, and to a lesser extent survival and development of nymphs reared on the artificial diet. Five- to six-day-old eggs had higher hatch rates, and nymphs survived longer and developed faster than nymphs from younger or older eggs. There were negative associations between the number of eggs placed on the membranes and both hatch rate and establishment of crawlers. Eggs oviposited on and then subsequently removed from plants held under long-day conditions (14:10 [L:D] h) or high light intensity (≈36,000 lux) had higher hatch rates than eggs oviposited under short-day conditions (10:14 [L:D] h) or low light intensity (≈11,000 lux). Long-day conditions during oviposition also significantly enhanced survival of nymphs through day 20 and developmental rate for day 6 counts. Light intensity, at least for the range tested here, did not significantly affect development or survival of whitefly nymphs.