摘要
为了经济有效地在大田应用EgNPV防治灰茶尺蛾 ,在室内进行EgNPV的毒力测定 ,试验表明致死中量LC50 为 1.13× 10 6PIB/mL ,90 %的致死量为 1.83× 10 7PIB/mL ,在 95%置信范围内 ,上限为 1.96× 10 7PIB/mL ,下限为 1.7× 10 7PIB/mL。用 2× 10 7PIB/mL浓度对不同龄期幼虫的感染试验表明 ,1 2龄效果最好 ,达 90 %以上。不同世代感染试验表明 :第 2、3、4、7代防治效果较好 ,高达 90 %以上 ,而第 5、6代效果不好 ,因此病毒增殖与大田防治工作应尽量避免在高温 ,干旱季节进行。另外探讨了适用大田防治的病毒增殖方法。
Aiming to economical and effective control of Ectropis grisescens warren in fields, the bioactivity of Ectropis grisescens Nucleopolyhedrovirus (EgNPV) was determined in laboratory. The medial lethal concentration (LC 50 ) of EgNPV againnst second third instar host larvae was 1.13 ×10 6 PIB/mL, and the 90% lethal concentration (LC 90 ) was 1.83×10 7 PIB/mL with 95% confidence limits from 1.70×10 7 to 1.96×10 7 PIB/mL. When exposed to EgNPV at the concentration of 2×10 7 PIB/mL, Ectropis grisescens larvae in their first and second instars were more sensitive than the individuals in the late instars. Second to third instars of Ectropis grisescens larvae from fifth and sixth field generations in dry and torrid season were less sensitive to EgNPV than the second, third, fourth and seventh generations in moderate seasons. Several methods of multiplication of EgNPV for control of the pest in fields were developed as well.
