阿维菌素对斜纹夜蛾3龄幼虫的亚致死效应研究

Sublethal Effect of Abamectin on 3rd Instar Larvae of Prodenia litura

采用常规的生物测定方法和酶活力测定方法,研究阿维菌素亚致死剂量对斜纹夜蛾生长发育及解毒酶的诱导效应,以了解阿维菌素对斜纹夜蛾的影响,并为指导其合理使用提供理论依据。结果表明:随着剂量的增大,阿维菌素对斜纹夜蛾的亚致死效应逐渐增强。当剂量达到LC20时,与对照相比,化蛹率降低了13.04%,蛹重减轻了24.56%,羽化率降低了18.22%,孵化率减少了11.90%,成虫寿命缩短了22.65%,单雌产卵量减少了10.62%,但幼虫发育历期却延长了0.57 d,且下一代的发育历期延长了1.02 d。另外,经过不同时间、不同亚致死剂量处理后,斜纹夜蛾3龄幼虫体内的羧酸脂酶活性均出现不同程度的上升。处理36 h后,LC10、LC15和LC20试验组的羧酸脂酶活性比对照分别提高了16.59%、20.24%和22.76%。但谷胱甘肽S-转移酶和多功能氧化酶O-脱甲基活性在试验期间无显著变化。结果说明阿维菌素能够影响斜纹夜蛾的生长发育,且对其体内的解毒酶系产生一些影响。

Effects on the growth, development, fecundity and activities of carboxylesterase, glutathione s-transferase and acetyl cholinesterase by sublethal doses of abamectin were investigated in the 3rd instar of Prodenia litura in the laboratory with conventional methods. Results showed that compared with the control, pupation rate decreased by 13.04%; the weight of pupae reduced by 24.56%; emergence rate reduced by 18.22%; egg hatchability decreased by 11.90%; adult longevity reduced by 22.65% and oviposition numbers of female dropped by 10.62%; development duration of larvae added by 0.57 d; next generation longevity added by 1.02 d were observed when exposed to sublethal doses LC20 of abamectin. Furthermore, the sublethal effects of abamectin on detoxification enzymes were also studied. It had obvious effect on activities of esterase. After exposure to abamectin at LC10 LC15 and LC20 for 36 h, the activities of esterase increased by 16.59%, 20.24% and 22.76% compared with the control. But the activities of glutathione S-transferase and mixed function oxidase were compared between abamectin treated larvae and the control, and no significant difference was observed, suggesting that abamectin at sublethal concentrations had no obvious effect on activities of the two detoxification enzymes. These results suggested that abamectin can disturb the life duration of P. litura, and influence some enzymes in its body.