杨树黄叶螨不同药物防治试验

通过对朝阳市杨树黄叶螨进行不同药物不同浓度防治试验,结果表明:喷洒不同药物对杨树黄叶螨杀虫效果差异显著,以杀螨醇和敌螨丹2种农药杀虫效果最好,杀螨率分别为99.3%~100%和99.4%~100%;不同浓度的杀螨醇杀虫效果差异极显著,以400倍浓度效果最好,叶螨死亡率在99.7%以上。     

扑利旺防治柑橘红蜘蛛的应用技术研究

为探索扑利旺在柑橘红蜘蛛上的应用效果，开展了扑利旺防治柑橘红蜘蛛卵室内试验以及在不同虫口基数和不同温度条件下的田间试验。结果表明：扑利旺可明显抑制柑橘红蜘蛛卵的孵化，且孵化后幼螨存活率降低，并对幼螨、若螨和成螨均有较好的防治效果。生产使用中，在虫口基数低（2-3头/叶）或春季红蜘蛛发生期，推荐扑利旺200-300倍喷雾处理或扑利旺500倍+24%螺螨酯5000倍喷雾处理；而在虫口基数高（9-10头/叶）或秋季红蜘蛛繁殖高峰期，推荐扑利旺200-300倍+ 24%螺螨酯5000倍喷雾处理来控制柑橘红蜘蛛的危害。     

73%炔螨特乳油防治苹果全爪螨效果研究

73%炔螨特乳油防治苹果全爪螨效果研究结果表明,该药剂对苹果全爪螨有较好的防效,且对果树安全、持效期长,具有一定的推广应用前景。生产上建议使用浓度为2 000～3 000倍液,施药间隔期7～10 d。     

浏阳霉素对两种螨的室内毒力测定与田间防效

为评估浏阳霉素对柑橘全爪螨和棉二斑叶螨的毒杀活性,测定了该药剂对他们的生物活性。结果表明:浏阳霉素对柑橘全爪螨成螨的LC50值为0.19 mg/L,95%置信区间为0.13～0.45 mg/L,毒力回归方程为:y=0.978 31 x+2.863 7;浏阳霉素对棉二斑叶螨的LC50値为0.36 mg/L,95%置信区间为0.24～0.66 mg/L,毒力回归方程为:y=1.269 3 x+2.948 1;浏阳霉素使用浓度为2.00 mg/L时对柑橘全爪螨和棉二斑叶螨的螨卵有一定的杀伤力;当使用浓度为2.00 mg/L和1.00 mg/L时,处理36 h后对柑橘全爪螨和棉二斑叶螨具有较强的趋避作用。10%浏阳霉素EC使用量为30～40 mL/667m2,对柑橘全爪螨和棉二斑叶螨的防治效果最好,药后1～7 d防效分别达87.1%～95.5%和91.2%～94.4%。其效果与15%哒螨灵15 mL/667m2的效果相近。     

二甲氧香酯对柑橘全爪螨的毒力测定及田间防效

利用玻片浸渍法测定了二甲氧香酯对柑橘全爪螨的室内毒力,并严格按照田间药效规范,开展田间药效试验评价了5%二甲氧香酯EC对柑橘全爪螨的防治效果。结果表明,处理48 h后,二甲氧香酯及其制剂LC 50分别为174 mg/L和114 mg/L,其对柑橘全爪螨的毒力是螺螨酯原药的1.61倍和2.46倍。田间药效结果表明,施药后1~14 d,5%二甲氧香酯EC 125~250 mg/kg处理可达到最大防效94.0%,显著优于或与对照药剂240 g/L螺螨酯SC 60 mg/kg的防效相当。5%二甲氧香酯EC可有效防治柑橘全爪螨,且持效期长,对柑橘生长安全,值得推广应用。     

Synthesis and acaricidal activity of phenylpiperazine derivatives

We synthesized 33 new phenylpiperazine derivatives and assessed their acaricidal activity. These derivatives were synthesized through sequential reactions consisting of the sulfonylation of 2-substituted 4-methylaniline with chlorosulfonic acid, reduction with red phosphorus and iodine, alkylation by alkyl halide, cyclization with bis(2-chloroethyl)amine hydrochloride, and N-substitution reaction of phenylpiperazines with various reagents. All phenylpiperazines synthesized were evaluated for acaricidal activity and their structure–activity relationships discussed, it was found that 4-substituted 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]piperazine derivatives exhibited good acaricidal activity. Among them, 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]-4-(trifluoromethylsulfonyl) piperazine showed the highest level of activity against Tetranychus urticae and provided a high level of activity against Tetranychus kanzawai and Panonychus citri. In addition, studies on the effect at various stages of T. urticae exhibited that this compound showed good activity against both adults and eggs.     

辐照结合不同温度处理对柑橘红蜘蛛成螨的影响

【目的】研究辐照结合不同温度处理对柑橘红蜘蛛(Panonychus citri Mcgregor)成螨的影响,以寻求提高辐照处理柑橘红蜘蛛成螨效果的方法。【方法】以0,100,200,300和400Gy的剂量辐照处理柑橘红蜘蛛成螨后,分别置于5,10,15,20和25℃条件下饲养,观察成螨死亡率及其后代繁殖情况。【结果】同一剂量下,柑橘红蜘蛛成螨死亡率随温度升高而增大,辐照后置于低温条件下可抑制成螨的死亡;用400Gy剂量辐照处理柑橘红蜘蛛成螨后置于25℃条件下15d,可使成螨死亡率达到100.00%。低温对柑橘红蜘蛛成螨产卵量及卵的孵化率有显著抑制作用,成螨经100和200Gy辐照处理后置于5℃条件下,产卵量为0;成螨经300Gy处理后置于温度低于20℃(包括20℃)条件下,可100%抑制卵的孵化。【结论】当温度为5℃时,100Gy辐照处理柑橘红蜘蛛成螨即可达到100%不育。     

榆叶象甲在西宁地区生物学特性研究

榆叶象甲是西宁地区垂榆上的主要害虫之一,该虫在西宁地区每年发生一代,每头雌虫平均产卵量为14.8粒,产卵部位集中于叶背,卵期8d左右,幼虫历期25d左右,老熟后在叶柄基部作茧化蛹,蛹期16d左右,从9月下旬起成虫在枯枝落叶层内进入越冬状态。     

苦楝油防治桔全爪螨的研究

本文认为苦楝(Melia azedarach L.)油对桔全爪螨Panonychus Citri(McG.)的毒杀作用,可能是因油剂堵塞螨的气门造成窒息而死亡。用电镜扫描的方法比较了桔全爪螨和捕食螨的气门结构,指出气门结构的差异是产生选择毒性的主要原因。本文提出了乳化苦楝油的经济、简易、有效的配方和方法。室内测定,苦楝油对桔全爪螨LC_(50)为0.27％;大田防治试验的效果达93.7％,是一种优良的高效杀螨剂。利用植物油防治柑桔叶螨具有广阔的前途。     

Monitoring of spirodiclofen susceptibility in field populations of European red mites, Panonychus ulmi (Koch) (Acari: Tetranychidae), and the cross-resistance pattern of a laboratory-selected strain

BACKGROUND: Phytophagous mites such as the European red mite, Panonychus ulmi (Koch), are serious pests in European fruit tree orchards, and a number of acaricides are frequently used to control them. Spirodiclofen (Envidor^®) has been a commonly used acaricide for several years. In the present study, European field populations collected in 2009 and 2010 were checked for their susceptibility to spirodiclofen by using discriminating dose and full dose response bioassays. RESULTS: In 2009 and 2010, a total of 63 field populations (including winter eggs) of European red mites were collected in different European countries, and in several populations from south‐western Germany a shifting in susceptibility against spirodiclofen was observed. Full dose response bioassays on different developmental stages of field‐collected strains suggested an age‐dependent expression of resistance because eggs remain fully susceptible to spirodiclofen. Artificial selection with spirodiclofen of one of the field strains resulted in resistance ratios of > 7000. Synergism studies suggest a possible role of cytochrome‐P450‐dependent monooxygenases in spirodiclofen detoxification. Most of the other acaricides from different chemical classes displayed no or low cross‐resistance in a spirodiclofen‐selected strain. CONCLUSION: In order to preserve spirodiclofen as an important tool in spider mite resistance management, the efficacy situation should be continuously monitored, and it is suggested that spirodiclofen be alternated with acaricides coming from different mode‐of‐action classes. An observed age‐specific expression of resistance revealed full susceptibility of eggs, so targeting spirodiclofen particularly against eggs is likely to reduce the selection pressures imposed on other life stages. Copyright © 2011 Society of Chemical Industry