5种中草药提取物对菇蝇的毒杀活性

采用药膜法,以清水为阴性对照,测定了5种中草药提取物对菇蝇的毒杀活性,结果显示:在供试的5个浓度下,百部和苦参对菇蝇的毒杀活性显著,在50 mg/mL质量浓度下,处理12 h后,百部、苦参对菇蝇的毒杀活性分别是85.00%和81.67%,处理24 h,均达到了100.00%.川楝子、龙胆草、透骨草次之.通过LC₅₀的测定,结果显示,百部、苦参24 h毒杀LC₅₀分别是13.790 mg/mL和18.668 mg/mL.田间防效试验表明:百部和苦参提取物对菇蝇具有良好的药效,用药3天的防效分别达到73.66%和71.27%,用药7天后维持在75.00 %左右,与清水对照相比防效显著.建议在生产中轮流使用50 mg/mL的百部提取物和75 mg/mL的苦参提取物,在菇蝇发生初期及时喷雾防治.

Insecticidal acticity of the botanical extracts from 5 Chinese herbs against phorid flies

Using the residue method,with water as the negative control,we measured the insecticidal acticity of the botanical extracts from 5 Chinese herbs against phorid flies.The results showed that in the selected five concentrations,the insecticidal activity of Stemona japonica and Sophora flavescens is significant,under 50 mg/mL mass concentration,12 h after treatment,the insecticidal activity were 85.00%,81.67%,after 24 h,reached 100.00%.Melia toosendan、Gentiana scabra,Phryma leptostachya,take second place.Through LC₅₀ determination,the results showed that the 24 h LC₅₀ of St.japonica and So.flavescens were 13.790 mg/mL and 18.668 mg/mL.Field control effect test showed that the extract of St.japonica and So.flavescens has good efficacy against phorid flies,the control effect is 73.66% and 71.27% after three days,around 75.00% after 7 days,compared with clear water control.We recommend in production to use 50 mg/mL St.japonica and 75 mg/mL So.flavescens alternatively, at the beginning of the phorid flies season.