排序方式: 共有86条查询结果,搜索用时 15 毫秒
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通过田间调查,研究了棉铃虫卵和龟纹瓢虫、中华草蛉空间分布的关系。研究表明,棉铃虫卵和龟纹瓢虫、中华草蛉在棉株垂直各层上的数量间相关系数6月分别为0.5696、0.8620,7月为0.8300、0.9282,8月为0.9083、0.8201,除6月龟纹瓢虫外,其余皆达显着或极显着水平;垂直格局上棉铃虫卵和龟纹瓢虫扩散系数和久野指数间相关系数分别为0.8211、0.7791,皆达极显着水平;水平格局上棉铃虫卵和中华草蛉扩散系数和久野指数间相关系数分别为0.7925、0.5228,分别达极显着和显着水平。 相似文献
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王金福 《Entomologia Sinica》1999,(3)
本文对淡色库蚊(Culex pipiens pallens Coquillett)的毒死蜱抗性品系、抗一敏杂交品系及抗性酯酶B_2纯合品系在无杀虫剂压力选择下的抗性水平变化进行了研究。结果表明,在毒死蜱抗性品系中,抗性水平逐代下降,LC_(50)从F_0代的0.2099mg/L快速降至F_8代的0.0262mg/L,然后继续缓慢地降至F_(16)代的0.0207mg/L。从毒死蜱抗性品系中的这种抗性水平下降,可以推断该品系中并不是纯的高抗性酯酶基因扩增个体,在传代中抗性个体的比例由于其生物学方面的不适应性而逐步减少。本研究中的抗性品系与敏感品系的杂交群体的抗性变化趋势也证实了这种推理。在纯的抗性酯酶B_2基因扩增品系中,抗性水平则在后代中基本上保持稳定,并且所有的个体抗性水平和酯酶活力水平更趋集中。本文进一步对蚊虫抗性的演替进行了讨论。 相似文献
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The repellent efficacy of wood vinegar was assessed against mosquitoes under laboratory conditions at 1, 5, 10, 20, 40, 60 and 80% concentrations. The study evaluated whether wood vinegar is able to repel Culex pipiens pallens Coquillet and Aedes togoi (Theobald) from the human body and if so at what concentrations. The tests were conducted using the arm-in-cage method in 80 × 40 × 40 cm screened mosquito cages. The data were analyzed and compared with those of N,N-Diethyl-3-methylbenzamide (deet) at 10.3% concentration. The results showed that wood vinegar provided mosquito repellence of varying degree depending on the concentration used. The observed repellence averaged from as low as 39.6% at 5.0% concentration to as high as 100% at 80% concentration against Ae. togoi. Repellence against Cx. pipiens pallens was high being 90.3% at 20% concentration, 92.2% at 40% concentration, 93.9% at 60% concentration and 100% at 80% concentration. The duration of protection time tests showed that the 40% and 60% concentrations of the wood vinegar give protection from landing of Ae. togoi for a period of up to 7 h, though the lower concentration gave lower protection after the first five hours. The results indicated that wood vinegar has mosquito repellent characteristics that tend to vary with the concentration used and the species of mosquitoes. Wood vinegar in this case was very effective in repelling Cx. pipiens pallens, even at lower concentrations while higher concentrations were required to repel Ae. togoi. 相似文献
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瓢虫和草蛉对小麦挥发物组分的行为及电生理反应 总被引:4,自引:2,他引:4
利用触角电位(electroantennogram, EAG)和嗅觉测定技术,比较分析了4种捕食性天敌昆虫七星瓢虫Coccinella septempunctata、龟纹瓢虫Propylaea japonica、中华通草蛉Chrysoperla sinica和大草蛉Chrysopa septempunctata对麦蚜取食诱导小麦挥发物的行为和电生理反应,揭示了瓢虫及草蛉类天敌昆虫的嗅觉反应特点。4种捕食性天敌昆虫对麦蚜取食诱导挥发物都有较高的EAG反应值,七星瓢虫和龟纹瓢虫对6-甲基-5_庚烯-2-酮、6-甲基-5-庚烯-2-醇的反应值较大;中华通草蛉和大草蛉对6-甲基-5-庚烯-2-醇和水杨酸甲酯的反应值较大,七星瓢虫对6-甲基-5-庚烯-2-醇的反应值最大,为0.96±0.18 mV;4种天敌昆虫对苯甲醛的EAG反应值较低,对反-2-己烯醛无反应。“Y”型管嗅觉测定结果表明,4种天敌昆虫对2-莰烯、6-甲基-5-庚烯-2-酮、6-甲基-5-庚烯-2-醇和水杨酸甲酯具有正趋性。说明4种多食性的捕食性天敌昆虫对麦蚜取食诱导挥发物各组分的嗅觉与行为反应各具特点;寄主麦蚜生境中的嗅觉线索在这4种捕食性天敌昆虫的寄主定位和生境选择中起重要作用。 相似文献
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Adult female green lacewings, Chrysopa quadripunctata Burmeister, were attracted to traps baited with 45% isopropanol in an unsprayed apple orchard in Missouri, USA. No lacewings were attracted to the unbaited traps. To the best of our knowledge this is the first report on a semiochemical that attracts lacewings of this species. 相似文献
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黄蒿挥发油对蚊虫的毒杀活性及其化学成分 总被引:11,自引:2,他引:11
采用培养板浸液法和三角瓶药膜法研究了黄蒿挥发油对蚊虫幼虫和成虫的毒杀效果,采用GC MS-DS联用分析了其化学成分.结果表明,挥发油对淡色库蚊幼虫和成虫具有较高的作用效果,且作用速度较快.对幼虫处理后2 d的LC50值约为12.5 mg·L-1.综合毒力测定显示,挥发油对成虫具有明显的击倒和致死作用,1 μg·cm-2和10 μg·cm-2剂量24 h致死率分别为70%和100%.黄蒿含挥发油0.38%,共鉴定出38种化合物,检出物占总质量87.53%,其中萜烯类12种,占45.04%,为黄蒿挥发油的主要成分. 相似文献
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