共查询到10条相似文献,搜索用时 109 毫秒
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Worldwide, grasshoppers and locusts destroy several billion dollars (US) worth of crops every year. The known microbial and protozoan pathogens of grasshoppers and locusts are reviewed. They may be valuable control agents, particularly for some of the economically devastating locust species in Africa and Asia, and grasshopper species in North America and Asia. Aspects of the pathogenic process, if known, of fungi, protozoa, viruses and rickettsia towards acridids are discussed. Finally, production, formulation and application of these biocontrol agents are reviewed. 相似文献
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Dillon RJ Webster G Weightman AJ Dillon VM Blanford S Charnley AK 《Journal of invertebrate pathology》2008,97(3):265-272
The gut bacterial community from four species of feral locusts and grasshoppers was determined by denaturing gradient gel electrophoresis (DGGE) analysis of bacterial 16S rRNA gene fragments. The study revealed an effect of phase polymorphism on gut bacterial diversity in brown locusts from South Africa. A single bacterial phylotype, consistent with Citrobacter sp. dominated the gut microbiota of two sympatric populations of Moroccan and Italian locusts in Spain. There was evidence for Wollbachia sp. in the meadow grasshopper caught locally in the UK. Sequence analysis of DGGE products did not reveal evidence for unculturable bacteria and homologies suggested that bacterial species were principally Gammaproteobacteria from the family Enterobacteriaceae similar to those recorded previously in laboratory reared locusts. 相似文献
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国内外蝗害治理技术现状与展望 总被引:3,自引:0,他引:3
本文首先概述了国内外蝗虫发生与为害的态势,总结了现阶段我国蝗虫发生与为害的主要特点:即农田飞蝗暴发频繁而且严重,草原土蝗的发生时常造成严重的经济损失,而且侵入城市干扰市民生活,我国与周边国家之间蝗虫过境迁移频繁,使用化学农药污染环境和农产品;分析了国内外蝗虫防治对策与技术的发展现状,重点介绍了应急防治和可持续治理对策、... 相似文献
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蝗虫化学信息物质研究进展 总被引:2,自引:0,他引:2
详述了蝗虫主要化学信息物质的种类、功能及主要成分等研究进展。蝗虫化学信息物质包括种内通讯的化学信息素和种间通讯的化学信息物质。其中种内通讯的化学信息素主要有群居信息素、成熟信息素、产卵信息素(含促产卵化学信息素和群集产卵化学信息素)、性信息素、聚集信息素等;种间通讯的化学信息物质主要介绍用于防卫的化学信息物质,包括卵分泌的信息物质、特定腺体分泌的信息物质、粪便挥发的信息物质、口腔分泌物和内部毒素等,对其天敌均有一定的防卫作用。化学通讯是蝗虫种内和种间通讯联系的普遍方式。 相似文献
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Metarhizium flavoviride, a fungal pathogen of grasshoppers and locusts, appears to be an effective, non-chemical insecticide (mycoinsecticide) for control of grasshoppers and locusts. This study, conducted during June and July, 1997, examined the pathogenic potential of this entomopathogenic fungus to non-target avian species that encounter infected insect prey items or contaminated food sources. Ring-necked pheasant (Phasianus colchicus) chicks were exposed to one of three diets, (spore-coated feed, infected insects, or untreated feed), either from 4 to 9 days of age, or, from 35 to 40 days of age. Necropsies were conducted on birds 10 days and 46 days old, respectively. Neither consumption of infected insects, nor of spore-coated feed, resulted in pathological changes, or significant changes in weight, growth rate, behavior, or mortality rate. Histological examination of organs indicated either no changes related to treatment, or normal tissue responses to antigenic challenge. 相似文献
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河北省北部苔藓植物区系与地理分布研究 总被引:9,自引:0,他引:9
基于作者近年来在河北省北部实地考察和采集的2000余号苔藓植物标本,经过研究鉴定,现已知河北省北部有苔藓植物270种(包括4变种、3变型),分别隶属于36科104属。其中,丛藓科为第一大科,含18属49种;紫萼藓属为第一大属,含17种。利用丰富度指数公式,并通过与我国其它9个山地的比较,可以看出河北省北部是苔藓植物物种多样性较为丰富的地区之一。河北省北部苔藓植物区系成分以北温带成分为主(占总种数的54.07%),其次是东亚成分(占总种数的14.81%)。各类温带成分共计227种,占总种数的84.07%,该植物区系具有明显的温带性质。运用主成分分析(PCA)的方法将河北省北部与我国其它12个山地苔藓植物区系所构成的区系谱进行了定量研究。结果表明:河北省北部与小五台山、内蒙古间苔藓植物区系关系最为密切,而与处于南亚热带的九万山关系最远。利用聚类分析的方法,并结合13个采集地的地理位置和不同的生态环境特点,将河北省北部苔藓植物区系划分为两个地带,即:张北高原苔藓植物地带和冀北山地苔藓植物地带。结合13个采集地苔藓植物种数所占总种数的百分比水平分布图,可以比较直观地看出河北省北部苔藓植物种数在纬向上由东向西逐渐减少,在经向上西北部种类较少、东南部种类较多的水平分布特点;通过苔藓生活型分析可以显示出张北坝上高原、冀西北间山盆地气候寒冷、干燥,顶蒴藓类占绝对优势;而承德坝上高原、冀北山地、燕山山地气候较温暖、湿润,侧蒴藓类所占百分比明显增多。这些与河北省北部苔藓植物区划地带是基本一致的。 相似文献
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Ronny Larsson 《Journal of invertebrate pathology》1976,28(1):43-46
A case of spontaneous infection of Malamoeba locustae from a free-living indoor population of Lepisma saccharina is reported. The source of infection was probably a culture of Schistocerca gregaria reared in the same room. Measurements of fixed cysts from L. saccharina are compared with measurements of fixed and unfixed cysts from S. gregaria and with published data from other species of grasshoppers and locusts. 相似文献