当归和蓖麻乙醇提取液对甜菜夜蛾生长发育和繁殖的亚致死效应

Sublethal effects of Angelica sinensis and Ricinus communis extracts on the growth, development and fecundity of Spodoptera exigua Hübner

为探讨植物提取液对甜菜夜蛾的亚致死效应,本文建立了当归和蓖麻提取液毒力回归方程,测定了两种提取液亚致死剂量LC20和LC30对幸存亲代和F1代甜菜夜蛾生长发育和繁殖的影响。结果表明:与对照组相比,这两种提取物的两个亚致死剂量对亲代和F1代甜菜夜蛾2~5龄幼虫历期、亲代和F1代甜菜夜蛾蛹历期和雌雄蛹重均无显著影响;与对照组相比,当归LC20和LC30处理后亲代甜菜夜蛾产卵量分别下降21.4%和26.5%,而F1代分别下降45.4%和61.3%,蓖麻LC20和LC30处理后亲代甜菜夜蛾产卵量分别下降23.5%和27.3%,而F1代产卵量分别下降52.7%和61.0%;蓖麻LC20和LC30处理不会显著影响亲代甜菜夜蛾化蛹率和羽化率,而当归LC30显著降低了其化蛹率和羽化率;与对照组相比,当归LC20和LC30对F1代甜菜夜蛾化蛹率无显著影响,但LC30显著降低了其羽化率,蓖麻LC20和LC30显著降低了其羽化率且LC30显著降低了其化蛹率。这两种提取物的两个亚致死剂量作用后都干扰了甜菜夜蛾性比,当归LC30处理后亲代甜菜夜蛾雌雄性比为1∶0.5,蓖麻LC30处理后F1代甜菜夜蛾雌雄性比为1∶2.1。本文揭示了当归和蓖麻提取液亚致死剂量对甜菜夜蛾生长发育和繁殖有一定抑制作用,可为植物提取液亚致死效应研究提供理论依据。

The toxicity regression equations for Angelica sinensis and Ricinus communis were established,and the sublethal dosage（LC20and LC30） effects of the two extracts on the growth,development and fecundity of beet armyworm（Spodoptera exigua Hübner） and its F1 progeny were determined in this paper.The results suggested that sublethal dosages of the two extracts had no significant effects on development duration of 2nd^5th instar larvae,pupal duration or male/female pupal weight of surviving parent and F1 progeny of S.exigua.The fecundity of parent S.exigua decreased by 21.4% and 26.5% respectively in A.sinensis LC20 and LC30 treatments,compared with the control.Also the fecundity of S.exigua F1 progeny decreased by 45.4% and 61.3% respectively in LC20and LC30treatments of A.sinensis.Similarly,the fecundity of parent S.exigua decreased by 23.5% and 27.3% in LC20while that of the F1 progeny decreased by 52.7% and 61.0% respectively in R.communis LC20and LC30treatments.While pupation and emergence rates of parent S.exigua were not significantly affected by R.communis LC20and LC30treatments,the two indices significantly decreased under A.sinensis LC30treatment.Compared with the control,A.sinensis LC20and LC30 had no significant effect on pupation rate of S.exigua F1progeny,while A.sinensis LC30significantly decreased emergence rate of S.exigua F1progeny.Also R.communis LC20and LC30significantly decreased emergence rate of S.exigua F1progeny and R.communis LC30significantly decreased pupation rate of S.exigua F1 progeny.After treated with LC20and LC30 sublethal dosages of the extracts,adult sex ratio 1136 orders of surviving parent and F1 progeny of S.exigua were severely distorted.Meanwhile A.sinensis and R.communis LC30 dosage largely affected the adult sex ratios of S.exigua parent and F1 progeny,with sex ratios（♀∶♂） of 1∶0.5 and 1∶2.1,respectively.Our study revealed that sublethal dosages of the two extracts had some inhibitory effects on the growth,development and fecundity of S.exigua.The study therefore provided the theoretical basis for studying the sublethal effects of plant extracts.