宁夏罗山不同林分凋落物微生物群落特征

宁夏罗山国家级自然保护区是宁夏重要的天然林区，研究罗山生态系统变化对进一步加强生态保护意义重大。凋落物是连接森林生态系统土壤和植被生态过程的关键纽带。文中以宁夏罗山具有代表性的天然油松林(Pinus tabulaeformis forest)、青海云杉林(Picea crassifolia forest)和油松-山杨针阔混交林(mixed forest of Pinus tabulaeformis and Populus davidaiana)凋落物为研究对象，通过分析不同林分凋落物化学组成、凋落物微生物群落结构及多样性，揭示宁夏罗山不同林分凋落物化学组成差异和微生物群落特征。研究结果表明：罗山三种典型林分凋落物的各化学组分中都是OC含量最高，各林分凋落物OC含量排序为青海云杉林>针阔混交林>油松林。针阔混交林凋落物化学组分中TN含量最高，且差异显著。青海云杉林凋落物化学组分的C/N最高，且差异显著。不同林分凋落物微生物群落结构差异显著，青海云杉林凋落物微生物生态网络较复杂，微生物群落之间联系更紧密。综合分析表明，影响凋落物微生物群落组成和多样性的因素中，OC和TK分别是影...     

微生物降解农药的研究进展

在农药的微生物降解研究中,分离构建一种由天然微生物构成的复合系,将其应用于被污染的环境是消除农药污染的一个有效方法。本文综述了环境中降解农药的微生物种类、微生物降解农药的机理、在自然条件下影响微生物降解农药的因素及农药微生物降解研究方面的新技术和新方法。     

微生物除草剂与生物安全

随着人类环境意识的提高和农业可持续发展的需要,高效、环保微生物除草剂的研究越来越显示其重要的社会意义和经济价值。本文概述了微生物除草剂的种类、剂型及特点,介绍了利用微生物及其天然产物防治杂草的潜在优势和目前国内外的研究进展,尤其是对微生物除草剂的生物安全性进行了评价。     

天然产物除草剂研究进展

本文综述了天然产物除草剂即生物源除草剂的基本概念、特点、分类和研究进展,概括了天然产物除草剂面临的问题及发展方向。主要介绍了植物源除草剂和微生物源除草剂的研究概况,为应用天然产物进行杂草防除提供理论依据,促进天然产物除草剂的研究。     

美国生物农药的主要类别

美国登记注册的生物农药主要分为生物化学农药和微生物类农药,其中生物化学农药包括引诱剂、驱避剂、天然昆虫/植物生长调节剂及除草剂、信息素、其他生化农药等;微生物类农药包括细菌、真菌、病毒、酵母、原生动物、工程菌、转基因植物等。     

我国微生物农药的研发与应用研究进展

病虫草害危害粮食生产，大量施用化学农药导致农药残留、环境污染等问题日益严峻。微生物农药作为生物农药主要类型之一，因其具有残留少、对人畜毒害性低等特点近年来得到迅速发展。本文梳理了我国微生物杀虫剂、杀菌剂和除草剂在生防菌株筛选、产品创制与应用等方面的研究进展，并对微生物农药的发展提出了建议和展望，可为行业相关单位和研究人员提供参考。     

梭梭保护酶活性与土壤微生物量的关系

以准噶尔盆地南缘梭梭(Haloxylon ammodendron)为研究对象,研究其 CAT,POD 和 SOD 活性变化,分析梭梭生境土壤含水量及土壤微生物多样性变化.结果表明:土壤含水量随着土壤深度增加而逐渐减少;在天然样地、交错带样地、人工样地中,交错带样地细菌和放线菌含量最高,说明该区域内土壤微生物活跃.从人工梭梭到交错带梭梭再到天然梭梭,POD 活性没有显著变化,CAT 和 SOD 活性逐渐降低,说明人工种植的梭梭需要经过一段时间适应该区域干旱环境,并逐渐转化为天然梭梭.通过研究发现,人工种植梭梭对梭梭群落恢复和发展有着积极作用.     

微生物蛋白质组学的研究进展

随着蛋白质组学研究技术的发展,微生物蛋白质组学研究具有突破性的进展。简要介绍蛋白质组学的分类,概括5种蛋白质组学技术,综合分析极端微生物、放线菌、病原菌以及群体微生物蛋白质组学研究及应用的最新进展。     

不同利用强度下草原土壤微生物的生物量和数量的动态研究

以内蒙古克什克腾旗西部的典型草原为研究对象,根据对草原利用强度的不同,将其划分三个不同区域,研究了各区域土壤中微生物数量、微生物生物量和土壤呼吸强度的季节动态以及利用强度对他们的影响.结果表明:微生物数量、微生物生物量以及土壤的呼吸作用强度均有较明显的季节性变化,且峰值都出现在8月份.三者之间具有极显著的正相关关系;轻...     

微生物降解磺酰脲类除草剂的研究进展

磺酰脲类除草剂具有高效和高选择性等优点,但其微量残留在土壤环境中就会对敏感作物会产生药害。因此,解决其残留问题便成为当今的研究热点。其中微生物降解是磺酰脲类除草剂降解的最有效方法之一。本文综述了降解磺酰脲类除草剂微生物种类、降解机理及研究现状,并展望了微生物降解磺酰脲类除草剂修复污染土壤的前景。     

昆虫病原真菌在害虫防治中对天敌生物的影响研究进展

昆虫病原真菌是一类重要的微生物杀虫剂,广泛应用于农林害虫的生物防治。由于寄主范围广和主动侵染的特点,昆虫病原真菌在侵染、致死靶标害虫的同时,对包括天敌昆虫在内的非靶标节肢动物等会产生潜在的致病或亚致死风险。本文总结了昆虫病原真菌在害虫防治中的研究进展及对天敌生物的影响,并展望了昆虫病原真菌作为极具潜力的生物农药与天敌生物联合防治害虫的未来发展方向。     

Potential for microbial diuron mineralisation in a small wine‐growing watershed: from treated plots to lotic receiver hydrosystem

BACKGROUND: Since biological degradation processes are known to be a major driver of the natural attenuation of pesticide residues in the environment, microbial communities adapted to pesticide biodegradation are likely to play a key environmental role in reducing pesticide exposure in contaminated ecosystems. The aim of this study was to assess the diuron‐mineralising potential of microbial communities at a small‐scale watershed level, including a diuron‐treated vineyard (pollution source), its associated grass buffer strip (as a river protection area against pesticide runoff) and the lotic receiver hydrosystem (sediments and epilithon), by using radiorespirometry. RESULTS: Comparison of results obtained at different sampling sites (in both soil and aquatic systems) revealed the importance of diuron exposure in the adaptation of microbial communities to rapid diuron mineralisation in the vineyard but also in the contaminated grass strip and in downstream epilithic biofilms and sediments. CONCLUSION: This study provides strong suggestive evidence for high diuron biodegradation potential throughout its course, from the pollution source to the final receiving hydrosystem, and suggests that, after microbial adaptation, grass strips may represent an effective environmental tool for mineralisation and attenuation of intercepted pesticides. Copyright © 2009 Society of Chemical Industry     

微生物农药在俄罗斯的应用进展

微生物农药因其副作用小、对环境兼容性好而日益成为全球农药发展的一种趋势和方向。本文以细菌杀虫剂、真菌杀虫剂、病毒杀虫剂、微生物除草剂、植物生长调节剂、农用抗生素作为微生物农药的代表,介绍了微生物农药的研究、应用现状及其在俄罗斯的研究进展,并对我国与俄罗斯在微生物农药领域的合作进行了展望。     

茄二十八星瓢虫生物防治研究进展

从茄二十八星瓢虫的天敌昆虫、微生物农药、植物提取物3个方面介绍了茄二十八星瓢虫生物防治研究的概况,并提出了今后的研究方向。     

Manipulated precipitation regulated carbon and phosphorus limitations of microbial metabolisms in a temperate grassland on the Loess Plateau,China

Manipulated precipitation patterns can profoundly influence the metabolism of soil microorganisms. However, the responses of soil organic carbon(SOC) and nutrient turnover to microbial metabolic limitation under changing precipitation conditions remain unclear in semi-arid ecosystems. This study measured the potential activities of enzymes associated with carbon(C: β-1,4-glucosidase(BG) and β-D-cellobiosidase(CBH)), nitrogen(N: β-1,4-N-acetylglucosaminidase(NAG) and L-leucine aminopeptidase(LAP)...     

Mineralisation of atrazine, metolachlor and their respective metabolites in vegetated filter strip and cultivated soil

In vegetated filter strips (VFS) the presence of perennial vegetation, rhizodeposition of labile organic substrates and the accumulation of an organic residue thatch layer may enhance microbial numbers and activity, thereby increasing the potential for mineralisation of herbicides and herbicide metabolites retained during run-off events. The objective of this laboratory experiment was to compare the mineralisation of atrazine and metolachlor with that of their respective metabolites in VFS and cultivated soil. With the exception of total bacteria, propagule density of the microbial groups, endogenous soil enzymes and microbial diversity were higher in the VFS soil. This correlated with increased mineralisation of metolachlor and its metabolites in the VFS soil and indicates potential for VFS to curtail the subsequent transport of these compounds. In contrast, the mineralisation of atrazine and the majority of its metabolites was substantially reduced in VFS soil relative to cultivated soil. Consequently, the potential for subsequent transport of atrazine and many of its metabolites may be greater in VFS soil than in cultivated soil if reduced mineralisation is not offset by increased sorption in the VFS.     

长期定位施肥对旱作农田土壤有机碳及其组分的影响

基于田间定位试验,研究了长期施肥对旱作冬小麦农田土壤有机碳及其组分的影响,试验包括4个处理:不施肥(CK)、氮磷配施(NP)、化肥与有机肥配施(NPM)以及长期休闲地(BL)。结果表明:长期持续施肥30年后,在0~30 cm土层,NPM处理土壤有机碳、微生物量碳、潜在矿化碳以及碳库管理指数分别较CK提高了42.2%、55.9%、40.9%和40.0%(P0.05),NP处理土壤有机碳和微生物量碳与CK差异不显著,潜在矿化碳和碳库管理指数分别提高了29.1%和20.0%(P0.05),施肥对两种活性有机碳含量的影响在15~30 cm土层表现更加显著;与种植作物相比,长期休闲显著降低了土壤潜在矿化碳含量,BL处理较CK降低了20.5%(P0.05)。相关性分析表明,土壤有机碳、潜在矿化碳、微生物量碳以及碳库管理指数两两之间存在着显著的相关性,且有机碳组分含量与土壤有机碳含量在处理间变化具有一致性(除NP处理外),两种活性有机碳相对含量在各处理间差异均不显著。总的来说,长期持续施入有机肥能够有效地增加旱作农田土壤有机碳同时增加其活性组分,有助于培肥地力和土壤固碳。     

Factors in the Success and Failure of Microbial Agents for Control of Migratory Pests

Microbial control agents generally kill insects more slowly than chemical pesticides, and fast-moving migratory pests may not at first sight appear to offer the most promising targets for microbial control. Operators responsible for control may need to have recourse to chemical control agents. Nevertheless, there are many occasions when pests breed and feed outside the crop and a microbial control agent can be used. Similarly, immature stages may cause little damage and early treatment in the crop can avoid damage. Microbial control agents are particularly likely to be favoured if the pest breeds in a conservation area, and if a publicly-accountable agency is responsible for control.Other key points of importance are the IPM context, in particular detection, planning and forecasting of outbreaks and the role of natural enemies.With these points in mind, we identify several locust and grasshopper systems where microbial control is becoming established; additionally, Sunn pest of wheat and Armyworm are identified as promising situations forbreak microbials.