共查询到16条相似文献,搜索用时 109 毫秒
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落叶松球蚜是严重危害松树的害虫之一,主要以化学农药进行防治。防治时用药面积大、用药量大,因而对防治农药的生态安全性要求高。主要阐述了微生物天然产物农药米尔贝霉素在欧洲对落叶松球蚜的防效及对生态安全的影响,为我国应用米尔贝霉素防治落叶松球蚜提供了理论依据。实验室条件下,把1%米尔贝霉素乳油稀释为0.075%,用药5 d后对初孵若虫、老熟若虫的防效分别为100%和98%。田间应用时,用药5 d、12 d后,防效为100%和98%。此药剂在田间应用后没有引起鸟类死亡;未发现对周围的蜜蜂有明显的影响及引起搬家、离巢现象;在离水域30 m外用药,也未发现对水生生物造成伤亡现象。 相似文献
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东莨菪内酯的纯度与其杀螨活性的相关性 总被引:1,自引:0,他引:1
[目的]以黄花蒿丙酮提取物为载体,采用叶碟浸渍法测定比较不同纯度的东莨菪内酯对朱砂叶螨卵、幼螨和成螨的触杀活性.[结果]不同纯度的东莨菪内酯对朱砂叶螨卵的活性有一定的差异,处理120 h孵化抑制率均低于50%,对幼螨和成螨的活性呈起伏式增加,处理48 h作用效果最佳的含量均表现在73.45%,其LC50值分别为89.63、97.34 mg/L.[结论]东莨菪内酯对朱砂叶螨的生物活性并不是纯度越高越好,在提取物中含有一定的原料杂质反而对药效有一定的增效作用. 相似文献
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丁醚脲防治柑橘红蜘蛛的应用研究 总被引:1,自引:0,他引:1
通过2年4地的田间药效试验,研究了新型硫脲类杀虫杀螨剂丁醚脲防治柑橘红蜘蛛的应用技术。结果表明,50%丁醚脲可湿性粉剂在175~250 mg/kg剂量下对柑橘红蜘蛛的防效与调查时间有关,其1~7 d的防效呈上升趋势,10~15 d防效最佳,20~30 d防效开始下降。50%丁醚脲可湿性粉剂防治柑橘红蜘蛛推荐剂量为200~250 mg/kg,在发生始盛期施药,并因正温度系数的特性,需要在晴天施药。本文还探讨了丁醚脲的应用策略,为该药剂应用的深度开发提供有益参考。 相似文献
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红树植物提取物的杀螨活性试验 总被引:5,自引:0,他引:5
采用叶片残毒法测定了16种红树植物甲醇提取物对柑橘红蜘蛛的杀螨活性。结果表明,海芒果、苦槛蓝、苦榔树和黄槿对柑橘红蜘蛛雌成螨的触杀活性高,药液质量浓度为10g/L时,24h的校正死亡率达90%以上;榄李、海漆和水黄皮有中等杀螨活性,校正死亡率为66.90%~74.19%;其余植物的杀螨活性低,校正死亡率在50%以下。海芒果、苦槛蓝、苦榔树、黄槿和榄李对雌成螨的致死中浓度(LC50值)分别为1.8416、2.8757、2.9218、4.9325、6.5728g/L。红树植物提取物对柑橘红蜘蛛卵也有触杀活性,其中苦槛蓝、苦榔树、木榄、海漆、老鼠簕、海芒果、白骨壤和草海桐的杀卵活性高,药液质量浓度为10g/L时,校正死亡率在80%以上。 相似文献
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Herbivory induces systemic production of plant volatiles that attract predators of the herbivore: Extraction of endogenous elicitor 总被引:7,自引:0,他引:7
Marcel Dicke Peter Van Baarlen Rob Wessels Herman Dijkman 《Journal of chemical ecology》1993,19(3):581-599
It was previously shown that in response to infestation by spider mites (Tetranychus urticae), lima bean plants produce a volatile herbivoreinduced synomone that attracts phytoseiid mites (Phytoseiulus persimilis) that are predators of the spider mites. The production of predator-attracting infochemicals was established to occur systemically throughout the spider mitein-fested plant. Here we describe the extraction of a water-soluble endogenous elicitor from spider mite-infested lima bean leaves. This elicitor was shown to be transported out of infested leaves and was collected in water in which the petiole of the infested leaf was placed. When the petioles of uninfested lima bean leaves were placed in water in which infested leaves had been present for the previous seven days, these uninfested lima bean leaves became highly attractive to predatory mites in an olfactometer when an appropriate control of uninfested lima bean leaves was offered as alternative. The strength of this effect was dependent on the number of spider mites infesting the elicitor-producing leaves. Higher numbers of spider mites resulted in an elicitor solution with a stronger effect. In addition, spider mite density was important. The elicitor obtained from one leaf with 50 spider mites had a stronger effect on the attractiveness of uninfested leaves than the elicitor obtained from three leaves with 17 spider mites each. This suggests that the stress intensity imposed on a plant is an important determinant of the elicitor quantity. While the elicitor has a strong effect on the attractiveness of uninfested leaves, spider mite-infested leaves are still much more attractive to predatory mites than elicitor-exposed leaves. The data are discussed in the context of systemic effects in plant defense and the biosynthesis of herbivore-induced terpenoids in plants. 相似文献