【作者】 王允场；

【导师】 刘怀； 邓新平；

【作者基本信息】 西南大学 ， 农药学， 2009， 硕士

【摘要】 巴氏钝绥螨是一种对柑桔全爪螨具有较好控制效果的捕食螨。本研究以巴氏钝绥螨为研究对象,在室内条件下分别从生物测定、捕食效能、生命表及酶活性四个方面,主要讨论了巴氏钝绥螨对11种农药的敏感性,哒螨灵、阿维菌素和甲氰菊酯3种药剂亚致死剂量LC₂₀及哒螨灵不同亚致死剂量(LC₂₀、LC₃₀和LC₄₀)对巴氏钝绥螨捕食作用的影响,亚致死剂量药剂对其实验种群发育繁殖及GSTs活性的影响,为进一步保护和利用天敌,进行可持续综合治理,提供一定的理论依据。主要研究内容结果如下:1 11种药剂对巴氏钝绥螨的毒力测定采用叶片残毒法在室内进行了哒螨灵等11种药剂对巴氏钝绥螨雌成螨的毒力测定试验。结果表明,菊酯类的甲氰菊酯对巴氏钝绥螨具有最高的毒力,大于一同参试的有机磷类药剂,其LC₅₀为0.3923 mg/L,阿维菌素对其毒力最小,LC₅₀为173.6564 mg/L。11种供试药剂对巴氏钝绥螨的毒力大小依次为:甲氰菊酯＞辛硫磷＞果圣＞对硫磷＞马拉硫磷＞氧乐果＞甲氨基阿维菌素苯甲酸盐＞水胺硫磷＞三氯杀螨醇＞哒螨灵＞阿维菌素。2哒螨灵、阿维菌素和甲氰菊酯亚致死剂量LC₂₀对巴氏钝绥螨的安全评价采用叶碟法,以柑桔全爪螨若螨为猎物研究了桔园常用药剂阿维菌素、哒螨灵和甲氰菊酯3种药剂亚致死剂量对巴氏钝绥螨功能反应的影响及负效应评价。结果表明,3种药剂中,甲氰菊酯对巴氏钝绥螨捕食功能的影响较大;亚致死剂量药剂对巴氏钝绥螨功能反应模型的基本结构没有改变,但影响了模型的各项参数。药剂处理后巴氏钝绥螨最大日捕食量降低,处理猎物时间延长,捕食速率和寻找效应减弱。同时也发现,甲氰菊酯对巴氏钝绥螨总影响值E最大,严重影响繁殖力,表现为高毒,而阿维菌素影响最小,表现为无毒,相对较为安全。3不同亚致死剂量的哒螨灵对巴氏钝绥螨捕食作用的影响在室内研究了不同剂量的哒螨灵作用下巴氏钝绥螨对柑桔全爪螨的功能反应。结果表明,随着剂量的增加,巴氏钝绥螨的捕食量显著减小,功能反应模型的参数有所改变,寻找效应也明显的降低。以不同剂量的药剂仅处理柑桔全爪螨时,LC₄₀处理组捕食量明显增加。4哒螨灵亚致死剂量对巴氏钝绥螨实验种群发育繁殖的影响在适宜的综合实验条件下通过构建生命表,研究了哒螨灵亚致死剂量对巴氏钝绥螨生长发育及种群动态的影响。结果表明,哒螨灵亚致死剂量对当代巴氏钝绥螨的产卵量和成螨寿命无显著影响;三种剂量对F₁代的幼螨期和整个世代均比对照显著延长;LC₃₀处理产卵期、平均产卵量和日平均产卵量都显著延长或增加;施药前后各项种群参数也有一定的差异,内禀增长率和周限增长率降低,而世代平均历期和种群加倍时间延长,尤其是LC₄₀处理,r_m、R_n和λ明显低于对照,则其对F₁代表现出一定的抑制作用,降低了种群的增长速率。5亚致死剂量哒螨灵对巴氏钝绥螨体内GSTs影响采用微量滴度酶标板法测定了哒螨灵亚致死剂量对巴氏钝绥螨谷胱甘肽-S-转移酶活性的影响。用亚致死剂量的哒螨灵处理巴氏钝绥螨24 h后,药剂处理组的比活力比对照组有所增大,其中LC₄₀显著增高。从GSTs的动力学研究表明,巴氏钝绥螨经药剂处理后GSTs的K_m比对照降低,但差异不显著;LC₂₀处理其不同时间后,对其体内的谷胱甘肽-S-转移酶具有一定的时间效应。更多还原

【Abstract】 Amblyseius barkeri is a common natural enemy in citrus orchard and it plays an important role in control ofPanonychus citri McGregor.The study on the susceptibility of Amblyseius barkeri to 11 insecticides,effects of sublethal doses(LC₂₀ of pyridaben,abamectin and fenpropathrin,LC₂₀,LC₃₀ and LC₄₀ of pyridaben ) on predation of Amblyseius barkeri,influence of sublethal doses of pyridaben on population dynamics and GSTs of Amblyseius barkeri were conducted at the laboratory. The major results are as follows:1 Toxicity of 11 insecticides to Amblyseius barkeriToxicity of pyridaben and ten other insecticides to Amblyseius barkeri was determined using leaf residue method in the laboratory.The results showed that fenpropatbrin of pyrethroid pesticide had the highest toxicity to Amblyseius barkeri with LC₅₀ 0.3923 mg/L.Organophosphorus insecticides had the higher toxicity.And abamectin was safe to adult,with LC₅₀ 173.6564 mg/L.The order of toxicities of the 11 pesticides from high to low against the adult females of Amblyseius barkeri was fenpropathrin > phoxim > guosheng（Tobacco,Matrine） > parathion > malathion > omethoate > emamectin benzoate > isocarbophos > dicofol> pyridaben > abamectin.2 Assessment of the impact of abamectin,pyridaben and fenpropathrin on Amblyseius barkeriLeaf disc bioassay was employed in the laboratory to investigate the effect of sublethal doses of selected pesticides,including abamectin,pyridaben and fenpropathrin,on the functional response of Amblyseius barkeri in preaying the Panonychus citri.Results revealed that,fenpropathrin showed a rather strong influence on the predation function of Amblyseius barkeri in contrast to abamectin and pyridaben.Except some changes of the parameters e.g,the functional response model of Amblyseius barkeri preaying on the Panonychus citri were all conformed to Holling’s typeⅡcurve in spite of pretreated with sublethal doses of these insecticides.The maximal predatory capacities of Amblyseius barkeri that pretreated by the three sublethal of pesticides were reduced.They were changed with prolonged handing time,declined predatory rates and the searching efficiencies than untreated.The E-values of fenpropathrin were severer than the other pesticides,and the fecundity of Amblyseius barkeri was significantly influenced.Therefore,abamectin was a relatively safe pesticide to Amblyseius barkeri and its affects were small to lethality and predation function. 3 Influence of sublethal doses of pyridaben on the function response of Amblyseius barkeri prisoner to Panonychus citriInfluence of the sublethal dose treatment of pyridaben to predatory response of Amblyseius barkeri was studied.The results showed that there were some changes in the parameters of the model and the predatory capacities and the searching capability of Amblyseius barkeri that pretreated by sublethal dose were significantly reduced.The predatory capacities of AmbIyseius barkeri were obviously enhanced when we treated the panonychus citri with sublethal dose.4 Impact of sublethal doses of pyridaben on experimental population of Amblyseius barkeriThe lifetable method was employed under the suitable comprehensive laboratory conditions to study the development and the fecundity of experimental population of Amblyseius barkeri treated by sulethal doses of pyridaben on.The results revealed that there were no significant difference in the life span and the fecundity per female between the treated population and the control.The growth duration of the larve and the total were lengthened after the mites in the nymph were treated with pyridaben.LC30 had obviously stimulated effects on the fecundity per femal,the fecundity per female per day and prolonged oviposition period.The parameters of the laboratory population were different in all treatments,namely intrinsic rate of increase（r_m） and finite rate of increase（2） decreased while the average generation time（T） and population double time（t） increased under the effects of the pesticide.The treatment at LC₄₀ could significantly decrease r_m,Rn andλ,so pyridaben may interfere with the F₁ of Amblyseius barkeri and population growth rate.5 Effects of sublethal doses of pyridaben on the specific activity in Amblyseius barkeriThe effects of sublethal doses of pyridaben on GSTs of Amblyseius barkeri were studied using microplate reader.The specific activity of GSTs of the Amblyseius barkeri were all increased while that of treated by LC₄₀ showed significant change after treated with sublethal doses about 24 hours. On the kinetic study,we found that the K_m value of GSTs decreased indistinctively in Amblyseius barkeri treated with pyridaben compared with that of the control.The GSTs activities were changed with time by LC₂₀ of pyridaben and had an obvious time effect.更多还原