Bioactivity of Five Insecticides Against Diamond Back Moth(Plutella xylostella L.)

Diamond back moth(Plutella xylostella L.)whose badly damage leads to losing so much in agriculture,is the major insect of Cruciferae vegetables. In the present study,dipping methods and ingestion methods were used to determine the bioactivity of five insectides against diamond back moth,respectively. The results indicated that the bioacitivity of 10% Chlorfenapyr EC and 5.44% Butenyl fipronil EC against diamond back moth were good after 72 h with dipping methods treatment,and,the LC50 was 1.758 mg/L and 2.289 mg/L,respectively. Besides,the bioacitivity of 5.44% Butenyl fipronil EC and 5% Fipronil SC against the insect were perfect after 72 h with ingestion methods treatment,the LC50 was 0.165 mg/L and 0.259 mg/L,respectively.