Toxicity and Persistence of Foliar Insecticide Sprays Against Black Vine Weevil Adults12

Effectiveness of insecticides against adult Otiorhynchus sulcatus (F.) was evaluated by applying candidate materials to Taxus media Rehder in the field and bioassaying the residues on the foliage in the laboratory. Carbaryl residues, even 1 h old, produced no mortality. Lindane residues, 24 h old, caused 100% mortality, but residues 3 days old were not toxic, Acephate was comparable to lindane in effectiveness but somewhat more persistent. Three-day-old bendiocarb residues caused 100% mortality, and 80% of the adults exposed to 1-wk-old residues were killed. Experimental pyrethroids permethrin and SD 43775 [Benzeneacetic acid (4-chloro-alpha- (1 methylethyl)) cyano-(3-phenoxyphenyl) methyl ester] caused rapid knockdown of adults, but those intoxicated during short-term (24 h) exposure to permethrin residues recovered. Long-term (5 day) exposure to 5-wk-old permethrin residues resulted in 54% mortality, whereas exposure to residues of SD-43775 up to 8-wk-old resulted in 100% kill.