水蓼不同提取液对一字纹稻苞虫的生物活性筛选

Bioactivity of various extractions from Polygonum hydropiper against Parnara guttata

基于均匀设计法研究水蓼(Polygonum hydropiper L.)全草的不同提取液对一字纹稻苞虫Parnara guttata Bremenet Grey的触杀和拒食活性。结果表明,乙醇浸提液对一字纹稻苞虫具有较高的触杀活性,48h的致死中浓度(LC50)为23.18mg·mL-1;水蒸汽蒸馏液对一字纹稻苞虫具有较强的拒食活性,24和48h的拒食中浓度(AFC50)分别为26.61和26.18mg·mL-1;丙酮浸提液对一字纹稻苞虫的触杀和拒食活性均不显著。54h的同时触杀和拒食活性浓度筛选的结果表明,乙醇浸提液70.02mg·mL-1和水蒸汽蒸馏液69.12mg·mL-1联合使用对一字纹稻苞虫同时触杀和拒食活性最好,死亡率达100%。

Contact toxicity and antifeedant activity of the extracts from herb Polygonum hydropiper L. against Parnara guttata Bremen et Grey was determined The ethanol extract had high contact toxicity with 48-h LC50 value of 23.18 mg·mL^-1 while the wet distillation liquid had strong antifeeding activity with AFCso values of 26.61 and 26.18 mg·mL^-1 at 24 hours and 48 hours respectively. Acetone extracts showed no obvious effect of contact toxicity and antifeeding activity. The results showed that the combination application of the ethanol extract at the concentration of 70.02 mg·mL^-1 and the wet distillation liquid at the concentration of 69.12 mg·mL^-1 had the best effect with 100% of death rate at 54 hours after application.