TOXICITY OF EMAMECTIN BENZOATE FOLIAR DISLODGEABLE RESIDUES TO 2 BENEFICIAL INSECTS

The persistence and residual contact toxicity of foliar dislodgeable e mamectin benzoate residues to Apis mellifera (L.) and Diglyphus isaea (Walker) were studied following applications to foliage at maximum ant icipated labeled use rate (0.0168 kg of active ingredient/ha). Bee mor tality from contact exposure to dislodgeable alfalfa residues aged for 3, 8, and 24 h was 100, 46, and 3%, respectively. This contact toxici ty was directly correlated with the magnitude of dislodgeable residues (9.1, 3.6, and 1.3 ng/cm(2), respectively), with a dissipation half-l ife of about 10 h. Similarly, D. isaea mortality from contact exposure to dislodgeable residues aged for 0.5, 1.0, 3.5, 35, and 60 h was 75, 65, 50, 20, and 15%, respectively; these residues (5.2, 5.0, 4.5, 1.4 , and <0.2 ng/cm(2), respectively) had a dissipation half-life of abou t 15 h. Therefore, these beneficial insects are expected to survive an d colonize treated crops within relatively short intervals (less than or equal to 24 h) after applications of emamectin benzoate.