Residual effects of carbaryl and dicofol on Aphytis holoxanthus Debach (Hymenoptera : Aphelinidae)

Aphytis holoxanthus Debach is an important biological control agent of Flor ida red scale, Chrysomphalus aonidum (L.). Laboratory tests quantified the mortality of this hymenopteran parasite caused by held residues of carbaryl and dicofol. Behavior and mortality of adult A. holoxanthus on carbaryl-tr eated "Hamlin" orange leaves were related to quantities of dislodgeable pes ticide residues over time as held residues weathered. After 24 h, mortality of A. holoxanthus by dicofol was not observed through day 31 when the expe riment was terminated. Our data showed that held-weathered carbaryl residue s killed A. holoxanthus for a period of up to 22 days posttreatment under s pring conditions in Florida. (C) 1999 Academic Press.