Laboratory Tests on the Toxicity of Chemicals for Cutworm (Agrotis Ypsilon Rot.) Larvae

Abstract

As showed in the petri-dish tests and pot tests of this experiment, the toxicity of the insecticides is influenced by the different methods of application, the chemicals used for both contact and stomach poison at the same time are more effective than that of individual In the emulsion form, to the 5th instar larvae, endrin shows the best effectiveness, the order of the decreasing toxicity of the chemicals tested is 0.06% endrin (active ingredient)＞0.06% aldrin＞0.06 dieldrin＞0.12% heptachlor＞0.03% aldrin＞0.03% endrin ＞0.03% dieldrin＞0.12% lindane=0.27% DDT. In the pot test, heptachlor can give better results but 0.24% of its active ingredient is minimum requirement. Still, it is less effective than 0.12% of endrin. In the powder form, endrin is more effective than heptachlor, 5% of endrin and 10% of heptachlor provide the better results.