Abstract：Testing result in laboratory showed that the toxicity of azadirachtin to Henosepilachna vigintioctopunctata was deducted with the increase of instars.The larva in 1-2 instar was the most sensitive,both of LC50 values were less than 0.2 mg·L-1. LC50 of azadirachtin to the 3-4 instar larva was less than 1.0 mg·L-1.The toxicity to the adult was decreased obviously,it’s LC50 was 2.122 7 mg·L-1 in 24 h.In the field,the effect of azadirachtin against larva was over 91.17 % at the 7th day at 400-800 times,it suggested the insecticide could be applied at 600-800 times in farming practice,the effect of azadirachtin against adult was over 81.20 % at the 7th day at 400-600 times,it suggested the insecticide could be applied at 400-600 times.
李兆防. 印楝素对不同龄期茄二十八星瓢虫的毒力及田间防效[J]. 中国蔬菜, 2009, 1(10): 55-58.
LI Zhao-fang. Laboratory Toxicity and Field Efficacy of Azadirachtin to Henosepilachna vigintioctopunctata (Fabricius) in Different Instars. , 2009, 1(10): 55-58.
