To provide the using information of disinfectors dose in the tobacco float seedling system,the efficacies of 90% lethal dose(EC90) of 10 disinfectors were examined by carrier germicidal test on breeding substrates,including polystyrene foam trays,polyvinyl chloride plastic film and stainless blade which were inoculated with Ralstonia solanacearum.

At same time, we also knew the LD100 of konjac is 3KR and LD50 is 1.

Effects of sub-lethal dosages abamectin on food intake and digestive enzyme activities of silkworm Bombyx mori L.;

Toxicity of emamectin to larvae of the diamondback moth, Plutella xylostella, at different temperatures was surveyed, and the effects on survivors of parent generation treated with sub-lethal dosage of the insecticide at 25℃ were studied with life table method.