Toxicity of Selected Insecticides to Clivina impressifrons

Fifteen insecticides were applied by micropipette to the ventral surface of the adult slender seed corn beetle, Clivina impressifrons LeConte. Some of the same insecticides were evaluated as seed treatments and soil treatments in the laboratory and greenhouse. Diazinon and parathion were the most effective insecticides when applied topically. Dimethoate, carbofuran, phorate, Dyfonate® ( O -ethyl S -phenyl ethylphosphonodithioate), Dasanit® ( O, O -diethyl O -[ p -(methylsulfinyl) phenyl] phospho-rothioate), and Dursban® ( O, O -diethyl O -(3,5,6-trichloro-2-pyridyl) phosphorothioate were slightly to moderately less effective. Diazinon and Dursban were most promising as seed treatments. Field conditions in 1969 were very favorable for germination and growth of corn seed, and the beetles caused only slight damage, even though the adults were relatively abundant.