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通过室内毒力测定与大田药效试验,对以水胺硫磷为主的10种复配杀螨剂进行筛选,结果表明,水胺硫磷加巴沙的混剂对桔全爪螨具有增效作用,其共毒系数为370,防治效果在90%以上,比水胺硫磷的防效提高了10%以上。 相似文献
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In determining the overall γ-diversity within a land use type or when assessing the impact of a land use on biodiversity one has to consider the hierarchically nested nature of the γ-diversity. In this study we used a hierarchical approach to examine the diversity of mites, Oribatei and Mesostigmata, in various forest types in Ireland. The study included sampling at regional, stand, individual tree and microhabitat scales. α- and β-diversity (species richness) was examined at each of these scales and the proportional contribution to the variation accounted for by each level of the hierarchy was quantified. β-Diversity generally accounted for at least 50% of the γ-diversity at all levels of the habitat hierarchy with average values varying from 34% between regions, to 57.5% between forest types within region, to 63% between trees within forest type and 63% between microhabitats within a forest type. Differences between the fauna of microhabitats within a forest type accounted for approximately 30% of the total variation while that of forest types within regions accounted for 10.5%. These results are similar to those reported in several other studies but the study quantifies the variation by examining the relative contributions of α- and β-diversity to species richness. Redundancy Analysis allowed the identification of the proportional contribution of the hierarchical components to the variation in community structure in a manner which has not been used before for these systems. 相似文献
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《Pedobiologia》2014,57(3):147-154
Fumigation is a common practice to control soil pathogens, but little is known about the impacts of fumigation on other soil biota groups. The purpose of this study was to investigate the effects of fumigation on soil biota, including microorganisms, nematodes, and microarthropods. Bacteria were the most resistant group and some survived following treatment with 2000 mg kg−1 dazomet. Some soil fungi survived 100 mg kg−1 dazomet, although they were mainly Trichoderma. The fungi pathogenic to ginseng were all killed at 100 mg kg−1, and showed both inter- and intra-species variation with respect to dazomet susceptibility. Among the nematodes, Aphelenchus was relatively resistant. The results suggested that susceptibility of soil organisms to dazomet differs between species, and that tolerant organisms may engage in recolonisation. In microcosm experiments, the microbial biomass and community were assessed using phospholipid fatty acid (PLFA) analysis while recolonisation of soil organisms was controlled by mesh size. The bacterial PLFA levels were changed little after fumigation, whereas the fungal PLFA levels gradually increased after fumigation. Principal analysis of the PLFA levels and the ratio of gram-negative to gram-positive bacteria showed that fumigation altered the microbial community. The number of nematodes did not recover even at 12 weeks after fumigation. The increased Collembolan numbers suggest that fumigated soil could be recolonised by specific organisms that have adapted to the conditions. In field experiments, we tested the ability of organic materials to enhance the recolonisation of fumigated soil by soil organisms. Bean powder and rice bran increased the microbial PLFA levels and nematode numbers at 6 weeks and 12 weeks after treatment, and the abundance of nematodes continued to increase 42 weeks after fumigation. The abundance of microarthropods was only slightly affected by the presence of the organic materials. We suggest that treating fumigated soils with organic materials is an effective technique to promote soil organism numbers. In addition, Trichoderma was observed to be relatively resistant to fumigation, and therefore, we propose that the fumigation effect can be improved by using a combination of resistant Trichoderma and dazomet. 相似文献
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为了明确柑橘始叶螨[Eotetranychus kankitus (Ehara)]及其天敌在茶园中的发生规律,为防治策略的制定提供参考数据。本研究针对重庆发生柑橘始叶螨的茶园进行为期1年的系统调查,并在室内测定了优势天敌捕食螨的捕食功能反应。结果表明:柑橘始叶螨在田间的种群数量少于茶跗线螨,但其主要在4—5月发生危害,对茶产业的影响较大;茶园天敌主要有巴氏新小绥螨和尼氏真绥螨,其中尼氏真绥螨对柑橘始叶螨有明显的跟随现象,在柑橘始叶螨的盛发期为优势天敌;室内测定尼氏真绥螨对柑橘始叶螨各螨态的捕食功能反应属于HollingⅡ型,取食幼若螨所需时间最短为1.08 h,且1天内取食高达55头。 相似文献
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2013年,新疆尼勒克养蜂受到了小蜂螨的危害,加之采蜜季节阴雨天气过多,导致蜂农养蜂受到沉重打击,给新疆尼勒克养蜂生产造成了很大影响,同时也对新疆黑蜂的保种、育王等工作造成一定的困难。针对这样的病害,新疆伊犁州尼勒克县种蜂场蜂业有关人员联系蜂农,讨论并制定了一系列的措施来预防下一年螨害继续危害新疆伊犁州尼勒克县种蜂场蜂群。 相似文献
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A·H植物杀螨剂的研究 总被引:1,自引:0,他引:1
筛选13种植物的根、茎、叶、种子提取物,组成14种不同的单方和复方,配制成喷雾和熏蒸剂型的杀螨剂。喷雾剂型复方植物杀螨剂,杀螨效果达到“杀螨剂一号”的95.2%;熏蒸剂型复方植物杀螨剂,杀螨效果达到“螨扑”的96.2%。A·H植物杀螨剂,在蜂群繁殖期防治蜂螨效果达到86%,在断子期达到94%。 相似文献