升华硫配合杀螨剂防治蜂螨效果的比较研究

[目的]比较升华硫配合杀螨剂防治蜂螨效果。[方法]2007~2009年3次于同一个蜂场采用同一种方法对升华硫配合杀螨剂防治蜂螨效果进行了试验。[结果]升华硫配合杀螨剂对于消灭存在蜂脾上及寄生于封盖蛹的蜂螨有明显效果,对于消灭成年工蜂身体上的蜂螨效果不明显。施药后杀灭大蜂螨的效果以第1天最佳,此后逐日减少;杀灭小蜂螨的效果以第2天最佳,此后逐日减少,表明在2~5 d再施治1~2次,可达到理想的防治效果。在小蜂螨大量滋生时,采用升华硫配合杀螨剂有较为理想的防治效果。[结论]该防治技术可为大、小蜂螨严重危害地区的养蜂生产提供服务。     

六点始叶螨对常用杀螨剂的抗药性测定

[目的]测定六点始叶螨对常用杀螨剂的抗药性。[方法]采用玻片浸渍法测定海南省海口市(R1)、儋州市(R2)与乐东县(R3)3地的六点始叶螨对9种杀螨剂的抗药性。[结果]对3个地区六点始叶螨的测定结果表明,始叶螨对9种杀螨剂均已产生抗药性,其中抗性指数较高的药剂是克螨特、哒螨酮和毒死蜱3种药剂,R3种群对克螨特的抗性最高,其抗性指数为39.0205;其次是水胺硫磷、三氯杀螨醇与虫螨腈,抗性指数在7.7441~15.0717;六点始叶螨对阿维菌素与甲氰菊酯抗性最低,仅为轻度抗性。不同地区之间六点始叶螨对同一药剂抗性指数差别不大。[结论]六点始叶螨对9种杀螨剂均已产生较高抗药性,杀螨剂应注意交替使用,同时结合使用一些新型杀螨剂,可达到更好的防治效果。     

Induction of cytochrome P450 monooxygenase activity in the two-spotted spider mite Tetranychus urticae and its influence on acaricide toxicity

Detoxification by cytochrome P450 monooxygenases is an important mechanism involved in pesticide resistance in insects and mites. The activity of these enzymes can be induced by a variety of chemicals. The aim of this study was to evaluate the effect of six P450 inducers (phenobarbital, barbital, 3-methylcholanthrene, geraniol, isosafrole, pentamethylbenzene), known to have an inducing activity in insects and mammals, on the O-deethylation activity in the two-spotted spider mite Tetranychus urticae. Treatment with barbital, phenobarbital and geraniol resulted in a dose-dependent increase in activity. Neither 3-methylcholanthrene, isosafrole nor pentamethylbenzene were effective inducers. Time course studies showed that induction by geraniol and barbital started rapidly within a period of 1-4 h after initiation of the treatment, while maximal activity was reached within 4 and 48 h, respectively. In addition, it was shown that induction with xenobiotic compounds can alter the monooxygenase-mediated acaricide tolerance in a susceptible strain of T. urticae. Although barbital induced higher levels of P450 activity, geraniol proved to be a better compound to decrease toxicity of the tested acaricides.     

Modelling population dynamics and response to management options in the poultry red mite Dermanyssus gallinae (Acari: Dermanyssidae)

The poultry red mite Dermanyssus gallinae is a major pest and widespread ectoparasite of laying hens and other domestic and wild birds. Under optimal conditions, D. gallinae can complete its lifecycle in less than 10 days, leading to rapid proliferation of populations in poultry systems. This paper focuses on developing a theoretical model framework to describe the population dynamics of D. gallinae. This model is then used to test the efficacy and residual effect of different control options for managing D. gallinae. As well as allowing comparison between treatment options, the model also allows comparison of treatment efficacies to different D. gallinae life stages. Three different means for controlling D. gallinae populations were subjected to the model using computer simulations: mechanical cleaning (killing once at a given time all accessible population stages), sanitary clearance (starving the mite population for a given duration, e.g. between flocks) and acaricide treatment (killing a proportion of nymphs and adults during the persistence of the treatment). Simulations showed that mechanical cleaning and sanitary clearance alone could not eradicate the model D. gallinae population, although these methods did delay population establishment. In contrast, the complete eradication of the model D. gallinae population was achieved by several successive acaricide treatments in close succession, even when a relatively low treatment level was used.     

用自助法统计推断炔螨特对桑树朱砂叶螨的防治效果

采用自助法(Bootstrap method)对炔螨特(propargite)防治桑树朱砂叶螨(Tetranychus cinnabarinus)的效果进行了统计推断。将4个试验点获得的田间防治效果数据进行平方根反正弦转换后,采用1000次自助法再抽样并作统计分析。结果表明,73%炔螨特乳油243．33mg/L有效质量浓度处理的第1、3、7天,田间防治效果的点估计分别为78．37%、86．03%和86．36%,置信区间估计依次为78．21%～78．52%、85．83%～86．24%和86．16%～86．55%;365．00mg/L处理的第1、3、7天,田间防治效果的点估计分别为88．14%、91．90%和91．23%,置信区间估计依次为88．01%～88．27%、91．78%～92．02%和91．09%～91．38%;486．67mg/L处理第1、3、7天,田间防治效果的点估计分别为92．82%、95．70%和95．11%,相应的置信区间估计依次为92．72%～92．93%、95．64%～95．76%和95．01%～95．20%。以上述的点估计为测试点,对各浓度处理后的不同天数的防治效果进行游程检测(Monte carlo Sig方法),随机性显著(p＞0．05)。通过Tamhane方法、Dunnett T3方法和Games-Howell方法对上述各处理的不同天数后的防治效果进行统计检测表明：炔螨特对桑园中朱砂叶螨的防治效果在防治后第3天达到高峰(p＞0．05),至第7天,243．33mg/L处理区的防治效果持平(p＜0．0000);而365．00和486．67mg/L处理区的防治效果呈下降趋势(p＞0．05)。以上统计推断结果显示：73%炔螨特乳油对桑树朱砂叶螨具有较好的田间防治效果,推荐使用的有效质量浓度为243．33mg/L。     

14种杀螨剂对不同地区苹果园二斑叶螨的防治效果评价

【目的】针对目前二斑叶螨抗性不断提高的事实,进一步了解二斑叶螨的田间抗性情况,并筛选出可供使用的杀螨剂种类。【方法】选取了14种我国当前农业生产上广泛使用的杀螨剂,分别对不同地区苹果园中的二斑叶螨进行了室内毒力测定试验,并观察其存活率以及后代的存活情况和性比。【结果】14种供试杀螨剂按照田间推荐剂量对二斑叶螨进行毒力测定,多数药剂未能表现出很好的杀虫效果;不同杀螨剂对不同二斑叶螨种群的药效也不同。【结论】二斑叶螨抗性积累比较严重,不同地理种群的抗性积累水平也存在较大差别。     

QuEChERS结合HPLC-MS/MS测定柑橘中5种杀螨剂残留

为了监测柑橘中阿维菌素、哒螨灵、螺螨酯、噻螨酮、乙螨唑残留量,应用Qu ECh ERS处理及高液质联用检测技术,研究建立柑橘中上述5种杀螨剂多残留分析方法。结果表明,琯溪蜜柚、芦柑、脐橙3种柑橘样品经Qu ECh ERS方法处理,净化效果良好。5种杀螨剂在0.5~500.0μg/L范围内线性关系良好(r2均大于0.999),仪器检出限(LOD)为0.01~0.30μg/kg、定量限(LOQ)为0.05~0.90μg/kg。加标回收试验,添加阿维菌素、哒螨灵、噻螨酮、乙螨唑为2.0~200.0μg/kg,螺螨酯为5.0~200.0μg/kg时,符合农药残留分析要求。该方法简便快速、灵敏度高、重现性好、检测浓度低,能够满足中国限量标准及多残留检测的要求。     

几种三氯杀螨醇替代杀螨剂对苹果害螨的防治效果

[目的]研究几种三氯杀螨醇替代杀螨剂对苹果害螨的防效.[方法]研究了3种低毒、低残留杀螨剂对苹果树螨害的防效,并对其田间应用效果进行了评价.[结果]5％唑螨酯、15％哒螨灵乳油和12.15％阿维·三唑锡防治苹果螨害平均防效分别为74.84％、71.22％、58.19％,施药后第7天防效最好,分别为99.46％、99.09％、98.83％,处理间差异不显著,3种杀螨剂对苹果螨害均有较好的防治效果.从速效性分析,15％哒螨灵乳油均优于5％唑螨酯、12.15％阿维·三唑锡,差异性达到极显著,防治后第1天分别为47.60％、45.10％、20.36％.3种杀螨剂施药后对果园害螨天敌均有一定影响,施药后第7天对天敌的消除率分别为31.9％、75.6％、91.8％.[结论]5％唑螨酯悬浮剂对果园天敌影响较小,哒螨灵乳油次之,阿维·三唑锡复方药剂相对影响较大.     

Spiromesifen resistance in Tetranychus urticae (Acari: Tetranychidae): Selection,stability, and monitoring

The two-spotted spider mite, Tetranychus urticae Koch, is an important pest of many agricultural crops. Studies on artificial selections, stability of resistance and monitoring of spiromesifen resistance were carried out to provide basic information for a spiromesifen resistance management program in T. urticae. Artificial laboratory selections for resistance to spiromesifen were performed in a population originating from a mixture of four field populations collected in commercial chrysanthemum fields in the State of São Paulo, Brazil. After 20 cycles of selection for spiromesifen resistance, the resistance ratio (RR₅₀) reached 121. Spiromesifen resistance was shown to be unstable in the absence of selection pressure under laboratory conditions. The frequency of spiromesifen resistance decreased from 75 to 0.15% in six months. The evaluation of 23 T. urticae populations from several crops in the States of Goiás, Mato Grosso and São Paulo in Brazil indicated that the susceptibility of the spider mites to spiromesifen was variable, with percentages of resistant mites ranging from 0.0 to 81.5%. The highest resistance frequencies were observed in ornamental plants (roses and chrysanthemum) in the State of São Paulo. Populations of T. urticae with up to 29.8% resistant mites were also detected in strawberry fields, in the same State. This is the first report on spiromesifen resistance in T. urticae on several crops in Brazil. Strategies for the management of acaricide resistance are discussed.     

9种杀螨剂对草莓二斑叶螨的室内毒力及田间药效试验

为了筛选对防治草莓上二斑叶螨Tetranychus urticae安全有效的杀螨剂,选用9种常用杀螨剂,采用叶片浸渍法测定它们对二斑叶螨的室内毒力及田间防治效果。结果表明:这9种药剂LC_(50)值的大小顺序为:20%甲氰菊酯乳油110 g/L乙螨唑悬浮剂240 g/L螺螨酯悬浮剂25%丁醚脲悬浮剂43%联苯肼酯悬浮剂22.4%螺虫乙酯悬浮剂30%乙唑螨腈悬浮剂0.5%苦参碱水剂1.8%阿维菌素乳油。其中,1.8%阿维菌素乳油的室内毒力最高,24、48、72 h后的LC_(50)分别为0.042、0.013、0.011 mg/L,其次是0.5%苦参碱水剂和30%乙唑螨腈悬浮剂,杀螨活性最低的是20%甲氰菊酯乳油,24、48、72 h后的LC_(50)分别为51.055、37.017、30.016mg/L;在此基础上选用7种药剂进行田间防效试验,30%乙唑螨腈悬浮剂5 000倍液对草莓二斑叶螨的药效最好,药后1、3、7d的防效分别达43.25%、57.75%、73.02%,防效显著高于其他6种药剂,0.5%苦参碱水剂1 200倍液次之,处理7 d后的防效为69.86%,其后是43%联苯肼酯悬浮剂,药后1、3、7d的防效分别为41.82%,54.77%,68.23%;速效性最低的是22.4%螺虫乙酯悬浮剂,药后1 d防效为31.45%;持效性最低的是240 g/L螺螨酯悬浮剂,7 d后的防效为58.44%。室内毒力测定结果最好的1.8%阿维菌素乳油和目前生产上常用的240 g/L螺螨酯悬浮剂的田间防效均不理想,1.8%阿维菌素乳油药后7d的防效为61.34%,仅高于240 g/L螺螨酯悬浮剂,可能与所选试验区域内经常使用这两种农药,导致此区域内的草莓二斑叶螨田间种群已产生抗性有关。因此,防治草莓二斑叶螨时建议在田间交替、轮换使用30%乙唑螨腈悬浮剂5 000倍液、0.5%苦参碱水剂1 200倍液和43%联苯肼酯悬浮剂。