Mixture Ratios Screening of Compound SpltNPV

In order to development spodoptera litura nucleopolyhedrovirus(SpltNPV) compound formulation with efficient and low toxicity,the median lethal concentration(lc50) against 4th-instar spodoptera litura of spltNPV,beta-cypermethrin,emamectin benzoate and chlorfenapyr were testes with bioassay method.Then with co-toxicity factor method,the associative actions of spltNPV and other three chemical pesticides were studied.The results showed that the co-toxicity factor of spltNPV and emamectin benzoate was the highest with 68.23.last the optimal mixture ratios were got 1:1 in combination of spltNPV and emamectin benzoate with quadratic regression rotation composite design method.