黒沙蒿提取物对粘虫的生物活性

Bioactivity of extracts from the plants of Artemisia ordosica against the armyworm Mythimna separata

采用室内生物测定方法,测定了黒沙蒿石油醚、氯仿、乙酸乙酯、正已烷和丙酮5种提取物对粘虫的生物活性.结果表明:黒沙蒿乙酸乙酯提取物对粘虫3龄幼虫具有较强的拒食、触杀和生长发育抑制作用,但胃毒作用相对较弱.黒沙蒿乙酸乙酯提取物处理24 h内的拒食率达到93.75%,拒食中浓度为8.4 mg/mL;触杀活性较显著,浸虫法测定的72 h的校正死亡率达89.29%;有较强的生长发育抑制作用,1 d后的生长发育抑制率为91.78%,2 d后是86.32%,平均蛹重169.1 mg,最终化蛹率为43.33%,且生长发育速度较对照缓慢.其它提取物也表现出一定的生物活性.

Bioactivity experiments were conducted with five kinds of extracts from a sand plant,Artemisia ordosica Kraschen, using Mythimna separata Walker as tested species. The results showed that Ethyl acetate extracts of Artemisia ordosica Kraschen had the highest bioactivity mainly in anti-feeding,contacting and inhibiting growth activities of the armyworm, but its stomach poison action was weak：In the treatment with Ethyl acetate extracts,the anti-feeding ratio of 3rd instars larva of the armyworm at 24 h after treatment reached 93.75% ,and the AFCso was 8.4 mg/mL. The extracts also displayed a highest contact efficiency against the armyworm,and the 72 h mortality with a dipping treatment reached 89.29%. Ethyl acetate extracts also had significant inhibition to growth and development of the armyworm,the inhibition rate at 24 h and 48 h after treatment were 91.78% ,86.32% respectively,and a pupation rate was only 43. 33%,the progress of growth and development of the armyworm was delayed. Other extracts,such as petroleum ether, chloroform, n-hexane and acetone,also showed biological activity in certain degree.