【作者】 贺金；

【导师】 刘永杰；

【作者基本信息】 山东农业大学 ， 农业昆虫与害虫防治， 2009， 硕士

【摘要】 斜纹夜蛾Spodoptera litura（Fabricius）是一种间歇性发生的世界性农业害虫,伴随农药的大量使用,斜纹夜蛾的抗药性问题越来越突出。阿维菌素是一种具有独特作用机制的神经毒剂,对环境友好、人畜安全。本文以斜纹夜蛾为材料,测定了斜纹夜蛾泰安种群对8种杀虫剂的抗性水平、评估了斜纹夜蛾对阿维菌素的抗性风险、比较了斜纹夜蛾不同种群解毒代谢酶的活性。1、用浸叶法分别测定斜纹夜蛾泰安种群对8种杀虫剂的抗性水平。斜纹夜蛾泰安种群对8种药剂产生的抗性倍数为:溴氰菊酯（138倍）>氯氰菊酯（97倍）>毒死蜱（15倍）>锐劲特（4.5倍）>除尽（3.2倍）>抑太保（3倍）>米满（1.9倍）>阿维菌素（1.4倍）。2、采用饲料浸毒法,用5.0mg/L阿维菌素对斜纹夜蛾进行抗性选育。在40～70%死亡率的选择压力下,经过饲养13代10次抗性筛选,得到斜纹夜蛾对阿维菌素的抗性为4.54倍。当抗性遗传h²=0.0505,杀死率80%～90%时,预计抗性增长10倍需要14～18代。斜纹夜蛾对阿维菌素的抗性发展速度相对较慢,产生高水平抗性的风险相对较低。3、测定斜纹夜蛾泰安田间种群、阿维菌素选育种群(F₁₃)及敏感种群羧酸酯酶、谷胱甘肽S-转移酶及多功能氧化酶的活性结果表明,斜纹夜蛾泰安种群和选育种群羧酸酯酶的活性分别是敏感种群的2.2和2.5倍,细胞色素P₄₅₀的含量分别是敏感种群的1.7和2.26倍,细胞色素P₄₅₀ O-脱甲基酶活性分别是敏感种群的1.43和1.76倍,斜纹夜蛾泰安种群和选育种群谷胱甘肽S-转移酶活性分别是敏感种群的1.26和1.08倍。用阿维菌素处理后羧酸酯酶和多功能氧化酶活性明显提高,而谷胱甘肽S-转移酶活性变化不大。结果证明斜纹夜蛾对阿维菌素的低水平抗性与羧酸酯酶和多功能氧化酶有关,与谷胱甘肽S-转移酶无关。更多还原

【Abstract】 The common cutworm, Spodoptera litura （Fabricius）, is a worldwide distributed agricultural pest occuring intermittently. Frequent use of chemical insecticides controlling S. litura had led to the development of insecticide resistance. Avermectin is an environmental friendly and human-animal harmless neurotoxin with special toxicious action. In this paper, the insecticide resistance levels of a field population of S. litura, resisntance risk to avermectin and detoxification enzyme activities were studied. The main results are as follows:1. Resistance levels of a Tai’an field population of S. litura to 8 insecticiedes were determined using leaf-dipping method. The results showed that the resistance levels of the field population were: Deltamethrin （138-fold）> Cypermethrin （97-fold）> Chlorpyrifos （15-fold）> Fipronil （4.5-fold）> Chioefenapyr （3.2-fold）> Chlorfluazuron （3-fold）> Mimic （1.9-fold）> Abamectin （1.4-fold）.2. Based on the bioassay results, 5.0 mg/L of avermectin as initial concentration was used to select first instar larvae of a susceptible population of S. litura by artificial diet dipping method. After 10 times of selection with avermectin during 13 continuous generations, the selection population obtained 4.54 folds of resistance compared with its unselected population. So we may infer from the above results that S. litura have low capability to develop resistance to avermectin. When realized heritability was 0.0505 and killing rate was 80% 90%, S. litura developing l0 folds of resistance to avermectin will need 14 to 18 continuous generations.3. Activities of carboxylesterase （CarE）, glutathione S-transferase （GSTs） and multi-function oxidase （MFO） of three different populations of S. litura were determined. The results showed that the CarE activities of Tai’an field population and the avermectin-selected population were 2.2 and 2.5 times high than that of unselected susceptible population. P₄₅₀ contents and MFO O-demethylase activities.of the field and selected populations were 1.7, 1.43 times and 2.26, 1.76 times high than that of unselected susceptible population, respectively. GSTs activities of the field and selected population were 1.26 and 1.08 folds of the susceptible population. Activities of CarE and MFO O-demethylase of three populations also were significantly increased by abamectin treatments while GSTs activities were almost not affected. Above results demonstrated that low level of resistance of S. litura to avermectin was related to carboxylesterase and multi- function oxidase, and had no relation with glutathione S-transferase.更多还原