亚致死浓度阿维菌素对荔枝叶螨种群发育的影响

于室内条件下研究了亚致死浓度阿维菌素对荔枝叶螨种群发育的影响。采用Potter喷雾法测得阿维菌素对荔枝叶螨成螨的亚致死浓度（LC10和LC30），并通过生命表方法研究了阿维菌素LC10和LC30浓度处理荔枝叶螨对其生长和繁殖的影响。结果表明:用阿维菌素LC10和LC30浓度处理荔枝叶螨后，与对照相比，其F0代产卵量分别减少79.16%和71.83%，雌成螨寿命亦均明显缩短。F1代幼螨期、产卵前期与对照相比均无显著差异，但卵孵化期、前若螨期、后若螨期均显著延长，其中LC30浓度处理后分别延长41.4%、39.4%和36.1%；F1代产卵量降低、产卵期缩短，其子代雌性比提高；F1代内禀增长率均降低，分别为0.127 3和0.075 8，而对照为0.132 3；世代平均历期缩短，种群倍增时间延长；净生殖率和周限增长率均降低。表明亚致死浓度阿维菌素对荔枝叶螨种群增长有一定的抑制作用。

Effects of sublethal concentrations of abamectin on development of Oligonychus litchii

In order to investigate the sublethal effects of abamectin on the development of Oligonychus litchii, Potter-spraying method was employed to test the sublethal concentrations (LC₁₀ and LC₃₀) of abamectin to adults of O. litchii, and analyzed the effects of sublethal concentrations (LC₁₀ and LC₃₀) of abamectin on the growth and reproduction of O. litchii by means of lifetables in laboratory. The results showed that the fecundity of female adults treated with abamectin at concentrations of LC₁₀ and LC₃₀ were reduced by 79.16% and 71.83%, respectively, and their longevities were also reduced significantly. The duration of larval and preoviposition stages of F₁ generation were not significantly different from that of the control. But the duration of egg, proto-nymph, deuto-nymph of F₁ generation were longer than that of the control, Which of the LC₃₀ treatment samples were increased by 41.4%, 39.4%, 36.1%, respectively. In addition, both the fecundity and egg laying period of female adults decreased,and the sex ratio of progeny of O. litchii was improved. After treated by sublethal concentrations (LC₁₀ and LC₃₀) of abamectin, the intrinsic rates of increase were decreased from 0.132 3 to 0.127 3 and then to 0.0758. The mean generation time was shorter than that of the control and the population doubling time was longer than that of the control. The net reproductive rate and finite rate increase were both decreased compared to the control. These results indicated that abamectin at sublethal concentrations had a negative effect on the population development of O. litchii.