阿维菌素对南方小花蝽抑制烟蚜的影响

在室内分别测定了阿维菌素类杀虫剂1% 9512-1乳油和虫螨克对南方小花蝽Orius similis的毒力，研究了无阿维菌素介入后南方小花蝽对烟蚜Myzus persicae捕食效应所受的影响，结果表明：阿维菌素类杀虫剂对南方小花蝽具有一定毒力，不同虫态对阿维菌素的敏感性有差异，卵的敏感性明显低于若虫和成虫；不同的阿维菌素类药剂对南方小花蝽的毒力存在差异，9512-1对南方小花蝽卵、若虫及成虫的LC_５０依次为11.2743±3.8613、2.6584±1.2139、2.4508±1.3266 mg·L^-１，虫螨克则为10.8699±3.7653、6.4422±2.8596、6.4738±3.0124 mg·L^-１；阿维菌素显著降低了南方小花蝽对烟蚜的捕食量和捕食能力，也降低了同种个体间的竞争能力；阿维菌素对南方小花蝽若虫的发育速率有显著的抑制作用，但对发育速率与取食量的线性关系无明显影响，而且对存活个体成虫期的产卵量无显著影响。

Effects of avermectin on the suppression of the peach aphid,Myzus persicae,by Orius similis

The toxicity of avermectins, 1% of 9512-1 EC and 1.8% of Chongmanke, against Orius similis were determined by laboratory bioassay. The effects of avermectins on the functional and numerical responds of O. similis were also studied. The results showed that avermectins were toxic to adults and nymphae of O. similis，while the sensitivity of eggs was much lower than adults and nymphae. Although the main component of 9512-1 and Jiqi Chongmanke was same, their effects on O. similis were different: for 9512-1 the LC_５０ against eggs, nymphae and adults were 11.2743±3.8613, 2.6584±1.2139, and 2.4508±1.3266 mg·L^１, respectively； for Chongmanke， 10.8699±3.7653, 6.4422±2.8596, 6.4738±3.0124 mg·L^１ respectively. The toxicity of 9512-1 on O. similis was higher than Chongmanke. Avermectin decreased the consumption and hunting capacity of O. similis on green peach aphids, and it also decreased individual competition ability of O. similis. Furthermore, it postponed the development of the nymphae, whereas it slightly affected the relationship between the growth velocity and the consumption as well as the oviposition.