定量评价天敌昆虫控害功能的铷元素标记技术

【目的】自然天敌对害虫种群起着重要的生态调控作用,定量地阐明天敌昆虫的取食关系及转移扩散规律,可为客观地评价天敌的控害功能提供依据。【方法】本文以苹果树与蛇床草Cnidium monnieri(L.) Cuss组成的微景观系统为研究对象,以蛇床草-胡萝卜微管蚜-异色瓢虫为研究主线,对植物和昆虫体内的铷元素含量进行检测。【结果】利用铷元素标记手段,结合室内和大田取样两种途径,通过测定天敌昆虫体内铷元素含量,可定量地评价种植功能植物提高果园天敌控害的作用。【结论】铷(Rb)元素标记技术是追溯天敌昆虫在农田生态系统中取食及转移扩散规律的重要手段。     

基于服务功能的昆虫生态调控理论

鉴于昆虫在植物传粉授精、害虫生物控制、土壤有机物分解中提供多种生态系统服务功能,本文在害虫生态调控、区域性害虫生态调控与生境管理的基础上,进一步提出基于多种生态服务功能的农田景观昆虫生态调控理论、方法与实践。认为:昆虫管理不仅仅是害虫的管理,还应包括有益昆虫(如传粉昆虫、天敌昆虫、分解昆虫)的管理,这种管理应从单一农田生态系统扩展到农田景观生态系统,充分考虑农田景观中昆虫的传粉功能、生物控害功能和分解功能,通过对功能植物、作物与非作物生境的空间布局以及时间序列上的生态设计,从空间上明确昆虫(包括害虫、天敌、传粉昆虫、分解昆虫)在不同生境中的转移扩散动态,从时间上掌握昆虫在不同寄主植物与非作物生境上的演替过程,从技术上着重发挥有利于昆虫的传粉功能、生物控害功能和分解功能的综合措施,在研究方法上突出使用稳定同位素、生态能量学、化学生态学等定量分析手段,研究景观区域内中"植物-昆虫"互作过程及其生态调控措施的作用,寻求不同时空条件下控害保益的关键措施,设计和组装出维持多功能的农田景观昆虫生态调控技术体系,创造有利于天敌控害、蜜蜂传粉、土壤分解的环境条件,以发挥昆虫类群在农田景观中最大的生态服务功能。     

农田景观格局对害虫天敌生态控害功能的调控作用

如何提升农田景观的生态服务功能是当前景观生态学和害虫防治学的前沿研究热点.基于区域农田景观格局可显著调节植物-植食性昆虫-天敌之间相互关系的理论基础,本文系统概括总结了农田景观格局及其变化对农田重要天敌多样性与生态控害功能的影响.从不同天敌类群的角度,分析了农田景观格局对捕食性天敌、寄生性天敌、有益微生物及其生态控害功能的调控作用.同时,对优化农田景观作物布局、采取合理的植被生境管理策略进行了展望.本文可为应用植被生境管理提升农田景观中天敌的生态系统服务功能提供参考,进一步促进区域生态农业响应"化学农药减量施用"的战略目标提供理论支撑.     

载体植物在温室作物害虫生物防治中的应用

增补式生物防治是利用天敌昆虫或捕食螨防治害虫最常用的方法,释放的天敌昆虫或捕食螨能否成功建立稳定种群,是决定其持久高效控害的首要关键因素。然而在生产应用中,经常因释放的天敌昆虫或捕食螨不能成功定殖而无法达到理想的防治效果。载体植物系统是天敌饲养和释放的新方法,结合了增补式和保护式生物防治的优点,既能实现天敌昆虫或捕食螨的大量饲养,又能为释放的天敌昆虫或捕食螨提供替代食物和栖息场所,促进其建立稳定的种群,对实现天敌昆虫或捕食螨高效持久控害具有重要的意义。本文系统介绍了载体植物系统的构建、国内外研究现状,指出了现存的问题,并给出相应的建议。     

基于CNKI分析的我国农田捕食性昆虫资源与应用

【目的】了解我国农田捕食性昆虫资源与应用研究态势。【方法】应用文献计量学方法,分析中国知网(CNKI)收录的全部年代的我国农田捕食性昆虫的中文文献。【结果】提取到544篇与农田捕食性昆虫相关文献及包含在这些文献中的1 747条关键信息词,研究内容主要包括以下5个方面:农田节肢动物群落与捕食性优势种;农田重要捕食者;捕食作用、食物网关系与生态服务价值评价;人工繁育、人工饲料与天敌释放应用;主要农作物的重要害虫种群及其综合管理。水稻与棉花生态系统及其中的捕食昆虫与害虫被重点关注。异色瓢虫Harmoniaaxyridis、七星瓢虫Coccinellaseptempunctata、龟纹瓢虫Propyleajaponica、黑肩绿盲蝽Cyrtorhinuslividipennis、青翅蚁形隐翅虫Paederusfuscipes、稻红瓢虫Micraspisdiscolor、尖钩宽黾蝽Microveliahorvathi等是农田中的优势性捕食性昆虫。【结论】在我国主要农田生态系统中,存在着丰富的捕食性昆虫资源,它们扮演着农作物害虫天敌的角色,实现对农作物害虫的生物防治或自然控制。建议加强对重要害虫种群发生机制研究,促进有利于天敌生存、保存的条件与方法研究,提高天敌的生态防控效能。     

农田景观格局变化对昆虫的生态学效应

景观格局变化是全球变化的一个重要内容。农田是由人类赖以生存所种植的人工栽培作物组成的生态系统。在该景观系统中,多种植物-害虫-天敌相互作用、相互制约,形成有机整体。研究农田景观格局对害虫和天敌种群动态影响,不仅在害虫生物防治的实践中有重要意义,而且对于揭示人类活动对生物多样性结构与功能的影响,阐明农田景观中生物多样性整合、维持机理有重大的理论意义。本文从农田景观格局的"质、量、形、度"4个方面,系统地论述了农田景观格局变化对害虫和天敌的作用,分析了农田景观的生物控制服务功能,指出了未来研究发展的方向。     

区域性农田景观格局对麦蚜及其天敌种群的生态学效应

明确农田景观格局对害虫及其天敌种群的生态学效应,是开展区域性害虫生态调控的基础.以前的研究大多集中于小空间尺度下、单个景观因子对昆虫种群的作用,而从省级范围的大空间尺度、多个景观因子的分析很少.本文以山东省区域性小麦种植区为研究对象,基于遥感影像和土地覆盖分类数据以及田间调查的昆虫种群数据,分析了景观组成类型(component type)、构成比例(component proportions)和形状结构(shape structure)多因子对麦蚜及其天敌寄生蜂和瓢虫种群的综合作用.结果发现,农田景观组成类型中斑块类型(patch type)越多,越利于麦蚜和天敌瓢虫种群数量的增长;且斑块密度(patch density)越大,越利于麦蚜寄生蜂和天敌瓢虫数量的增加;景观形状结构中边界密度(edge density)越高,也越利于麦蚜寄生蜂和天敌瓢虫种群数量的增加.进一步定量评估了农田景观组成类型、构成比例和形状结构对麦蚜及其天敌种群影响的作用大小.结果表明,三类景观格局因子对麦蚜影响较小,权重为9.81%;而对麦蚜寄生蜂的影响权重为25.87%;对天敌瓢虫种群高达47.86%.本研究清楚地表明,通过优化农田景观中作物与非作物生境布局,可直接调节和增加天敌昆虫种类与数量,有效控制和减少小麦蚜虫的种群数量,从而提高区域性农田景观中天敌昆虫的生物控害服务功能.     

稳定同位素分析在昆虫生态研究中的应用

综述了稳定同位素分析的原理与方法以及应用于昆虫生态研究的理论基础与进展,并对其发展前景进行初步探讨。该方法的应用以寄主植物同位素组成差异为前提,常用的同位素包括 D,13C,15N和18O,主要涉及确定食物来源,探寻寄主间转移规律及迁移路线、生态系统中物质与能量流动、食物网构建等方面。对长期保存标本与昆虫化石的同位素分析则扩展了研究的时间范围。同位素转化时间的确定、质量平衡方程和混合模型的应用则是验证相关生态问题的重要步骤;生态、生理和生化过程对同位素分馏的影响尚需深入研究。     

天敌昆虫抗药性研究进展

天敌昆虫抗药性研究在协调害虫化学防治和生物防治中有着重要的理论和现实意义,其研究的最终目的在于更好地推进抗性天敌在害虫综合治理(IPM)中的应用。抗药性天敌昆虫具有潜在的巨大价值。鉴于此,本文系统地综述了天敌昆虫抗药性最新研究进展,包括杀虫剂对天敌昆虫的影响、天敌昆虫抗药性现状、抗药性机理和限制天敌昆虫抗药性发展因素等。文章最后还对抗药性天敌昆虫的应用前景进行了展望。     

昆虫学专家介绍

<正>戈峰博士,中国科学院动物研究所研究员、博士生导师。主要从事昆虫生态学与害虫生态调控研究。近期重点:1)研究全球气候变化下"作物-害虫-天敌"的相互作用关系,分析不同类型昆虫对CO2浓度升高的响应机制;2)探讨华北农区棉花、小麦、玉米等主要作物所组成的农田景观中害虫、天敌的发生动态。     

Land‐use effects on terrestrial consumers through changed size structure of aquatic insects

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