【作者】 李辉；

【导师】 缪勇；

【作者基本信息】 安徽农业大学 ， 农业昆虫与害虫防治， 2015， 硕士

【摘要】 本文通过室内毒力测定和田间试验,研究了几种杀虫剂及其混剂对春甘蓝田菜青虫及捕食性天敌群落的影响。主要结果如下:1菜青虫对几种药剂的敏感性试验结果表明,菜青虫对阿维菌素和氯虫苯甲酰胺的敏感性较高,LC50分别为1.4085mg/L和2.9981mg/L,敏感性倍数分别是毒死蜱的57.98倍和27.23倍。在3种混剂中,菜青虫对阿维菌素+氯虫苯甲酰胺混剂的敏感性最高,LC50仅为0.7882mg/L,敏感性倍数是毒死蜱的103.59倍,共毒系数达233.7898,具有明显的增效作用。根据室内毒力测定结果和试验统计得出的毒力回归直线,得出菜青虫3龄幼虫对几种杀虫剂的敏感性大小顺序为:阿·氯混剂>阿维菌素>氯虫苯甲酰胺>氯·毒混剂≥阿·毒混剂>毒死蜱。2几种药剂对春甘蓝田菜青虫的防治效果试验结果表明,阿维菌素和氯虫苯甲酰胺对菜青虫均有很好的控制效果。毒死蜱对菜青虫的防治效果显著低于阿维菌素和氯虫苯甲酰胺,持效性较差。3种混剂对菜青虫均有很好的控制效果,尤其是阿·氯混剂和氯·毒混剂速效性和持效性都比较理想,通过药剂混用既减少了每种单剂的使用量,有助于延缓害虫抗药性的产生和发展,又可以兼治其它害虫以及解决了氯虫苯甲酰胺药效慢及毒死蜱药效较短的缺点,在生产上具有应用价值。3几种药剂对春甘蓝田天敌群落主要特征指数的影响研究结果表明,与空白对照处理相比,毒死蜱、阿维菌素、氯·毒混剂和阿·毒混剂处理对捕食性天敌个体数量有明显的负面影响,其中以毒死蜱的负面影响最大;氯虫苯甲酰胺和阿·氯混剂处理对天敌安全。毒死蜱和阿维菌素处理对天敌群落的物种丰富度有明显的负面影响,其他药剂处理无明显影响。各药剂处理对天敌群落的均匀度均无明显影响。毒死蜱处理对春甘蓝田捕食性天敌群落的多样性有一定的负面影响,其他药剂处理对天敌群落的多样性均无明显影响,氯虫苯甲酰胺处理对天敌群落的多样性略有提升作用。4几种药剂对春甘蓝田天敌-害虫益害比的影响试验结果表明,与对照处理相比,毒死蜱处理对春甘蓝田天敌-害虫益害比有较大的负面影响,平均值比仅为0.59,这与毒死蜱对甘蓝害虫防效不理想及对天敌影响较大有关。阿维菌素处理及阿·毒混剂处理对春甘蓝田益害比略有正面影响。氯虫苯甲酰胺处理及氯·毒混剂、阿·氯混剂处理春甘蓝田益害比较对照处理大幅上升,表明使用氯虫苯甲酰胺及氯·毒混剂、阿·氯混剂防治春甘蓝田菜青虫等害虫有助于保护加强天敌对害虫的自然控制作用。更多还原

【Abstract】 The effects of several insecticides on cabbage caterpillar(Pieris rapae)and the predatory natural enemy community in spring cabbage fields were studied based on the methods of insecticide bioassay in laboratory and the field experiment.The main results are as follows:1 Susceptibility of Pieris rapae to several insecticides in laboratoryThe results of toxicity tests in laboratory show that cabbage caterpillar is relatively sensitive to abamectin and chlorantraniliprole with LC50 of 1.4085 mg/L and 2.9981 mg/L respectively and their susceptibility is 57.98 and 27.23 times as much as that of chlorpyrifos respectively.Among the three insecticide mixtures,cabbage caterpillar is most sensitive to abamectin+ chlorantraniliprole mixture with LC50 of 0.7882mg/L and sensitive times of 103.59 as much as that of chlorpyrifos.The mixture of abamectin+chlorantraniliprole has obvious synergistic effect on cabbage caterpillar with co-toxicity coefficient of 233.7898.According to the results of toxicity tests in laboratory and the toxicological regression line of several insecticides against cabbage caterpillar,the susceptibility of 3 instar larvae of Pieris rapae to the insecticides is in order of abamectin+chlorantraniliprole mixture > abamectin > chlorantraniliprole > chlorantraniliprole+chlorpyrifos mixture ≥ abamectin+ chlorpyrifos mixture >chlorpyrifos.2 Control effects of several insecticides on Pieris rapae in spring cabbage fieldsThe results of field experiments show that both abamectin and chlorantraniliprole have excellent control effects on cabbage caterpillar.The control effects of chlorpyrifos on cabbage caterpillar are significantly lower than those of abamectin and chlorantraniliprole and its persistent control effect is not satisfactory.All the three insecticide mixtures have excellent control effects on cabbage caterpillar,especially the mixture of abamectin +chlorantraniliprole and the mixture of chlorantraniliprole + chlorpyrifos have both excellent fast and persistent control effects on cabbage caterpillar.The use of the insecticide mixtures can reduce the application dosage of single insecticide,is helpful to delay the emergence and development of resistance of insect pests to insecticides and is able to control other insect pests in the meantime.They have practical value in agricultural production.3 Effects of several insecticides on natural enemy community in springcabbage fieldsThe research results show that compared with the control treatment,the treatments of chlorpyrifos,abamectin,chlorantraniliprole+ chlorpyrifos mixture and abamectin+chlorpyrifos mixture have evident negative influence on the total individuals of predatory natural enemies and the treatment of chlorpyrifos has the greatest negative impact.The treatments of chlorantraniliprole and abamectin+ chlorantraniliprole mixture are safe to natural enemies.The treatments of chlorpyrifos and abamectin have evident negative impact on the species richness of natural enemy community and the other insecticide treatments have no evident influence.All the insecticide treatments have no significant effects on the evenness of natural enemy community.The treatment of chlorpyrifos has certain negative effects on the diversity of predatory natural enemy community in spring cabbage fields while other insecticide treatments have no evident negative influence and the treatment of chlorantraniliprole has some promotive effects on the diversity of natural enemy community in spring cabbage fields.4 Effects of several insecticides on the ratio of natural enemies to insect pests of natural enemy community in spring cabbage fieldsThe research results show that compared with the control treatment,the treatment of chlorpyrifos has relatively great negative impact on the ratios of natural enemies to insect pests in spring cabbage fields and the ratio of means is only 0.59,which is related to the unsatisfactory control efficacy of chlorpyrifos on major insect pests and the negative impact on natural enemies.The treatments of abamectin and abamectin+ chlorpyrifos mixture have a little positive impact on the ratios of natural enemies to insect pests in spring cabbage fields.Compared with the control treatment,the ratios of natural enemies to insect pests in spring cabbage fields under the treatments of chlorantraniliprole,chlorantraniliprole+ chlorpyrifos mixture and abamectin+ chlorantraniliprole mixture rise greatly and this indicates that the use of chlorantraniliprole,chlorantraniliprole+chlorpyrifos mixture and abamectin+ chlorantraniliprole mixture to control the insect pests such as cabbage caterpillar etc.is helpful to protect and increase the natural control effects of natural enemies on insect pests in spring cabbage fields.更多还原