Effect of Buprofezin onIcerya Purchasi andPlanococcus Citri

The effectiveness of buprofezin (aqueous suspensions from 25% wettable powder) on cumulative nymph mortality and reproduction of two homopterous pests,Icerya purchasi Maskell (Margarodidae) andPlanococcus citri (Risso) (Pseudococcidae), was investigated under laboratory conditions. Buprofezin was very effective against crawlers of both species. Dipping in concentrations of 0.002%, 0.01% and 0.05% (a. i.) resulted in 91–99% nymph mortality ofP. citri, whereas 100% mortality was recorded whenI. purchasi was treated at 0.05% (a. i.); the 3rd-instar nymphs ofI. purchasi were less susceptible to the chemical. Death of the larval stages occurred mainly during the molting process to the 2nd-instar nymphs. At 0.05%, buprofezin sprayed on adults slightly reduced fecundity and decreased egg hatch to 31% forI. purchasi and, depending on the exposure period of the females, to 49-7% forP. citri. Buprofezin at 0.05% exhibited strong ovicidal activity onP. citri, resulting in inhibition of over 80% egg hatch.