43%联苯肼酯悬浮剂防治草莓二斑叶螨药效试验

采用田间试验法评估43%联苯肼酯悬浮剂20、25、30 g·(667 m2)-1对草莓二斑叶螨的防治效果。结果表明:在二斑叶螨盛发初期施药1次,30 g·(667 m2)-1 43%联苯肼酯悬浮剂处理对草莓二斑叶螨的防治效果最佳,速效性好,持效期较长,药后7 d的防效在85%以上,且各处理对草莓生长和非靶标动物均未产生不良影响。     

4种药剂对二斑叶螨的室内毒力和田间防效

采用玻片浸渍法测定了依维菌素等4种药剂对二斑叶螨雌成螨的室内毒力,并进行了防治二斑叶螨的田间药效试验。室内测定结果表明,几种药剂对二斑叶螨的毒力顺序为：依维菌素>甲氰菊酯>高效氯氟氰菊酯>螺虫乙酯,其中依维菌素对二斑叶螨的室内毒力最高,其LC₅₀值为0.01 mg/L。田间试验结果表明,0.5%依维菌素乳油9、18 g/hm ²用量,药后3、7、10天对二斑叶螨的防治效果在90%以上,可作为防治二斑叶螨雌成螨的首选药剂。     

万寿菊提取物对山楂叶螨的触杀活性及酶活性的比较

万寿菊(Tateges erecta)为1年生草本,是分布于许多国家的观赏性植物,在我国已有千年的栽培历史,也是近年来研究较多的杀虫植物之一.万寿菊享有同印楝(Azadirachta indica)、川楝(Melia toosendan)、烟草(Nicotiana tibacum)、鱼藤(Derris trifoliata)同样的地位,成为从2 400种已记载控害植物中挑选出来的43种广谱控害植物之一,被誉为"控害的精华"(Grainge et al.,1988).     

Determination of susceptibility and resistance of some greenhouse populations of Tetranychus urticae Koch to chlorpyrifos (Dursban 4) by the petri dish–Potter tower method

The level of susceptibility of the two-spotted spider mite, Tetranychus urticae Koch, populations collected from greenhouses in Antalya and Isparta regions of Turkey against chlorpyrifos was determined by a petri dish bioassay method. This study consisted of two stages. In the first stage, using a diagnostic dosage (0.026 ml chlorpyrifos in 100 ml distilled water) it was determined whether these populations are resistant or susceptible to chlorpyrifos. Then, different dosages of chlorpyrifos were applied to resistant populations to determine LC₅₀ and LC₉₀ values. Resistant ratios of populations were calculated by dividing the LC₅₀ values of resistant populations by that of a susceptible population of T. urticae strain GSS. The resistance ratio of T. urticae populations collected from greenhouses ranged from 8.00 to 1,774.00. Results show that while three of the populations gathered from the Isparta region, where greenhouse vegetable growing has been increasing since 2000, are susceptible, two of them are only partially resistant to chlorpyrifos. On the other hand, all the two-spotted spider mite populations collected from the Antalya region, the centre of greenhouse vegetable production for many years, were found to be highly resistant to chlorpyrifos.     

光照对截形叶螨生长发育和繁殖的影响

长短光照对截形叶螨的影响有着显著差异，在30度时短光照明显延缓该螨的发育，Rm值相应降低，并且存活率和产雌卵率曲线均滞后于长光照处理。     

Esterase-mediated bifenthrin resistance in a multiresistant strain of the two-spotted spider mite, Tetranychus urticae

A field-collected multiresistant strain of Tetranychus urticae Koch exhibiting high resistance to bifenthrin was investigated in comparison with a susceptible laboratory strain. The esterase inhibitor S,S,S-tributyl-phosphorotrithioate (DEF) was able strongly to synergise bifenthrin toxicity in the resistant strain. Optimal conditions for determining esterase activities in T. urticae were determined, and a higher esterase activity towards several artificial substrates was found in this resistant strain, which had a preference for hydrolysing 4-nitrophenyl butyrate. Bifenthrin was able to bind the active centres of T. urticae esterases in vitro, as was determined after competition experiments by a Dixon plot, revealing a higher affinity of bifenthrin in the resistant strain. Bifenthrin-hydrolysing activity in the resistant and susceptible strains was examined in vitro and quantified with gas chromatography. A 7.2-fold higher metabolising rate was found in the resistant strain.     

欧亚旋覆花提取物对朱砂叶螨生物活性及其体内几种酶活性的影响

植食性害螨是危害农业生产的一个重要生物类群,我国每年用于主要作物的杀螨剂费用约90多亿元(师光禄等,1994)。朱砂叶螨(Tetranychus cinnabarinus)是其中一个重要的种类,可危害粮、棉、油、林木、果树等43科146种植物(李连昌等,     

7种杀虫剂对截形叶螨和二斑叶螨的防效试验

选用7种杀虫荆,采用培养皿叶背喷雾法对截形叶螨和二斑叶螨试验种群进行了药效试验.试验结果表明,0.5%君子剑乳油的药效最好,喷药后1 d就达到100%,表现出了好的速效性和高效性.由于0.5%君子剑乳油不仅药效快、药效高,而且是低毒和低残留的无公害生物农药,因此,是杀螨的首选药剂.