果樹的病害

果树的病害和一般植物病害一样可以分为寄生病害和非寄生病害。寄生病害中又有真菌病、细菌病、毒病和微小害虫寄生病害等;非寄生病害中有营养失调引起的病害,温度不当引起的病害,空气中气体成分不当引起的病害,日灼病,药害等。至于我国的果树病害,如苹果腐烂病则为苹果的主要病害(图1)。可是其他国家里苹果     

蓝色农业潜力大

“蓝色农业”即海洋农业。我国濒临黄海、渤海、东海。南海,海岸线绵长,约一万多公里,有着辽阔的海滨、众多的岛屿和优良的港湾。我国的浅海滩涂面积广阔,海藻资源丰富,种类繁多,海藻生产有悠久的历史。海藻作为食用,有其特殊的营养成分,对人类具有一定的营养价值和疗效作用。海藻中主要含有大量的碳水化合物,是藻体的主要部分。①褐藻碳水化合物包括褐藻胶、褐藻淀粉、褐藻糖胶、纤维素、低分子量褐藻糖类、中性单糖及糖苦等;②红藻碳水化合物包括琼胶、卡拉胶、红藻淀粉、低分子量的碳水化合物和其它红藻藻胶等;③绿藻碳水化合…     

食用菌主要病原真菌和细菌

食用菌已成为我国农业产业中的第五大作物。随着食用菌生产规模的扩大,病害日益严重,成为影响食用菌产量和品质的重要因素之一。本文概述了引起食用菌主要病害的病原真菌和细菌的种类、寄主范围、病害发生率以及发病症状,阐明了食用菌病害防治研究现状。同时也总结了一些病害的防治方法,为食用菌栽培、病害防治和抗病育种提供理论依据。     

基于文献信息的食用菌病害研究热点与趋势分析

病害是影响食用菌产量和品质的重要因素之一,目前尚缺少对食用菌病害研究现状与发展方向的直观了解。从2010年以来国内外发表的食用菌病害论文入手,对论文数量、发文期刊、被引率和研究机构进行了分析,展示了国内外食用菌病害的研究概况。此外,对相关论文进行了关键词共现分析,明确了国内外食用菌病害研究的热点。分析显示,绿霉病、褐斑病、蛛网病、病毒感染、湿泡病和软腐病是目前国内外最受关注的6类食用菌病害,干泡病的关注度日趋减少,而蛛网病侵染的食用菌种类持续增加。结合历史发文动态研究了食用菌病害的发生趋势,并认为环境有害微生物检测、消毒剂筛选和食用菌土传真菌病害防控将是未来食用菌病害的重点研究领域。     

马铃薯黄萎病研究现状

马铃薯黄萎病是一种重要的世界性病害之一,为土传兼种传维管束病害,危害大且防治困难。本文将该病害的分布与危害、症状、6种病原的形态学及其生物学特性、发病规律、病原检测技术和病害综合防控措施等方面研究进行了综合概述,可为该病害的相关深入研究提供理论指导。     

辽宁省水稻病害调查研究

这份调查研究,经1954年至近年,逐步采集和鉴定了辽宁省水稻病害约30余种。鉴定后绘制病原菌原图,并对每种病害的症状特点、病原菌、发生分布、防治要点等做扼要附述。以便对我省水稻病害有一概括的了解,和水稻病害诊断鉴定的参考。     

单克隆抗体在植物病理学中的应用及其研究进展

植物病理学家的特殊任务包括植物病害的诊断、病原物的鉴定和检测、病原物的特性研究以及寄主-病原物相互关系的研究。植物病理学家的根本目的在于保持植物健康,也就是防治病害。病害的准确诊断无疑是防治的前提条件。病原物被鉴定得越快速、越准确,就越能快速地实施正确的防治。病害诊断和病原检测的常规方法主要包括病害的症状学、显微镜技术、微生物学技术、生物鉴定技术和血清学技术。免疫化学技术对病害的快速准确的常规诊断极其有用,对植物病原的鉴定和定量分     

生物多样性控制作物病害研究进展

自然资源的合理利用和生态环境保护是人类实现可持续发展的基础, 生物多样性的研究和保护已成为世界各国普遍关注的重大问题。农作物病害是农业生产上重要的生物灾害, 是制约农业可持续发展的主要因素之一, 抗病品种大面积单一化种植导致了农业生物多样性水平严重降低, 因而农业生物多样性的过度丧失已成为可持续农业所面临的主要难题。利用生物多样性持续控制作物病害能减轻作物病害发生和作物产量损失, 达到保护作物多样性, 减少农药过量施用给农业生态环境造成破坏的最终目的, 而揭示生物多样性控制作物病害的机制能有效地指导生产上对不同作物进行合理布局和轮换, 建立作物不同组合的优化搭配和种植模式。文章从分子、生理和生态水平研究农业生物多样性控制作物病害的机制、以及影响作物多样性控制病害的因素、覆盖作物等几方面对生物多样性控制作物病害的研究进展进行概述, 同时对今后生物多样性控制作物病害机制还需加强的研究部分进行了展望。     

烟草苗期病原微生物病害发生及综合防治

烟草苗期主要病原微生物病害(如炭疽病、猝倒病、立枯病和根黑腐病)的发生流行对我国烟草生产的影响逐渐加剧,研究烟草苗期病害的防治措施变得尤为重要.探索烟草苗期主要病原微生物病害的发生规律和流行趋势,以及当前的防治手段,可以保障烟草生产的质量和数量.基于此,本文对烟草病原微生物苗期病害的防治方法进行了概述,为烟苗病害的研究提供了参考和思路.     

人参主要非侵染性病害的预防

长期以来,人参非侵染性病害一直没有得到人参种植户的认识和重视。经过几年的生产实际观察、总结,发现人参非侵染性病害是对人参生长影响比较普遍的病害,必须加以预防。     

江苏省区域农业生态经济的时空变异分析

以江苏省徐连、沿海、宁镇扬、沿江和太湖5个经济区及其9个代表县市区域为研究对象,基于"社会-生态-经济"的系统分析,建立了包括目标层、准则层和指标层3个层次多指标的农业生态经济综合评价指标体系,采用主成分分析方法对评价指标体系进行检验、筛选,并以江苏省为案例,综合分析了农业生态经济系统的时空变异特征。结果表明:江苏省农业生态经济发展水平的时空变异明显,空间上,徐连、沿海、宁镇扬、沿江和太湖5个经济区表现出由北向南逐渐上升的趋势,且随时间的推移逐渐上升;时间上,徐连和太湖经济区农业生态经济发展水平在1999—2008年间呈持续上升,处于良好或优质协调状态。虽然两经济区的农业生态环境-经济发展协调发展水平均较高,但差距较大,徐连和太湖经济区的农业生态环境-经济发展协调度从1999年到2008年呈逐渐下降趋势,但总体上仍处于良好或优质协调状态。     

Regulatory impact on insect biotechnology and pest management

The application of insect biotechnology is promising for the development of environmentally compatible pest management solutions. As we have refined and enhanced genetic engineering techniques in several insect species that cause significant economic loss and public health injury, it has become clear that insect biotechnology will move forward as one of the key tools of pest management in agriculture and in the human environment. Well characterized genetic elements can be manipulated toward specific aims and maintain a viable insect, albeit one with diminished capacity to exchange genetic material, vector a virus or bacterium, or complete its life cycle. Despite this degree of knowledge and precision, there remain unanswered questions regarding environmental fate, release and public acceptance of this technology. The uncertainty surrounding any novel technology inevitably increases the level of regulatory scrutiny associated with its use. Although the term “insect biotechnology” has many connotations, it certainly includes the genetic modification of symbiotic or commensally associated microbes as a means of delivering a trait (e.g. a toxin) to manage plant and human diseases and insect pests. The distinction between this paratransgenic approach and direct genetic modification of insect pests is an important one biologically as well as from a regulatory standpoint. The regulatory framework for microbial applications to agriculture is in many instances in place; however, we must strive to forge the development of guidelines and regulations that will foster deployment of insect biotechnologies.     

慢性代谢性疾病的环境与遗传交互作用以及早期预防

随着我国经济的发展和营养与生活方式的迅速变迁,近年来我国居民肥胖、2型糖尿病等慢性代谢性疾病患病率激增,已成为影响国民健康最主要的威胁。有研究显示:与白种人相比,亚洲人具有较高的2型糖尿病遗传易感性,这可能与"代谢性肥胖"表型和遭遇营养转型中的"致肥胖环境"有关。大量的研究结果表明,此类慢性代谢性疾病是遗传和环境因素交互作用的结果。随着全基因组关联研究开展,目前已发现了20多个肥胖和2型糖尿病易感基因,不仅揭示了不同种族人群在基因结构和效应值方面存在着差异,但同时也发现遗传方面的差异仍无法完全解释东西方人在发病风险方面的不同。膳食、生活方式等环境因素仍被认为是2型糖尿病发病中的重要决定因素。在全基因组关联研究后时代,国际上的研究将更加强调基因—基因、基因—环境、基因—表型之间的交互作用对代谢性疾病的影响和相关的机制。事实上,有研究表明,各种基因多态性、炎性因子和脂肪细胞因子等都可能成为早期诊断的生物标记物,而通过改变膳食和生活方式则是目前国际公认的预防和控制慢性代谢性疾病最有效的方法。然而,我国尤为缺乏在大规模前瞻性流行病学研究中对导致慢性代谢性疾病流行的主要遗传和环境因素,以及基因—环境相互作用对健康的影响方面的系统的研究。而这类研究将为建立适用于中国人群遗传和表型特征的早期诊断生物标记物和有效预防干预策略奠定基础。     

生态条件的多样性变化对蜜蜂生存的影响

蜜蜂在整个生态系统中起着重要的传花授粉作用,是生态链中不可或缺的物种。随着现代农业的发展,蜜蜂赖以生存的环境遭到破坏,继而引发蜜蜂数量大幅减少,影响了蜂种的生存与可持续发展。总结了近年来生态条件的变化,归纳了影响蜜蜂生存的主要因素,分析了蜜蜂生存艰难的原因,提出了蜜蜂生存的关键问题,并展望了未来维持蜜蜂强群的主要研究方向。     

Antimicrobial peptides (AMPs): A promising class of antimicrobial compounds

Antimicrobial peptides (AMPs) are compounds, which have inhibitory activity against microorganisms. In the last decades, AMPs have become powerful alternative agents that have met the need for novel anti-infectives to overcome increasing antibiotic resistance problems. Moreover, recent epidemics and pandemics are increasing the popularity of AMPs, due to the urgent necessity for effective antimicrobial agents in combating the new emergence of microbial diseases. AMPs inhibit a wide range of microorganisms through diverse and special mechanisms by targeting mainly cell membranes or specific intracellular components. In addition to extraction from natural sources, AMPs are produced in various hosts using recombinant methods. More recently, the synthetic analogues of AMPs, designed with some modifications, are predicted to overcome the limitations of stability, toxicity and activity associated with natural AMPs. AMPs have potential applications as antimicrobial agents in food, agriculture, environment, animal husbandry and pharmaceutical industries. In this review, we have provided an overview of the structure, classification and mechanism of action of AMPs, as well as discussed opportunities for their current and potential applications.     

Use of endophytes as biocontrol agents

Plant diseases, caused by various microorganisms, including viruses, bacteria, fungi, protozoa and nematodes, affect agricultural practices and result in significant crop losses. Fungal pathogens are the major cause of plant diseases and infect most plants. Agrochemicals play a significant role in plant disease management to ensure a sustainable and productive agricultural system. However, the intensive use of chemicals has adverse effects on humans and ecosystem functioning and also reduces agricultural sustainability. A sustainable agriculture is achieved through reduction or elimination of fertilizers and agrochemicals, resulting in minimal impact to the environment. Recently, the use of antagonistic endophytes as biocontrol agents is drawing special attention as an attractive option for management of some plant diseases, resulting in minimal impact to the environment. Endophytes that resides asymptomatically within a plant, have the potential to provide a source of candidate strains for potential biocontrol applications. This review addresses biocontrol methods using endophytic fungi such as Colletotrichum, Cladosporium, Fusarium, Pestalotiopsis and Trichoderma species as an attractive option for management of some plant diseases. Potential endophytes are screened in vitro and in vivo to test their antagonistic actions by different mechanisms, including mycoparasitism, production of lytic enzymes and/or antibiotics and induction of plant defenses. Currently, efforts are being made to commercialize these biocontrol agents. A continued research pipeline consisting of screening, in vitro and in vivo testing, biomass production and commercialization of endophytes as biocontrol agents may contribute to sustainable agriculture.     

Verticillium wilt of olive: a case study to implement an integrated strategy to control a soil-borne pathogen

Olive (Olea europaea L.) is one of the first domesticated and cultivated tree species and has historical, social and economical relevance. However, its future as a strategic commodity in Mediterranean agriculture is threatened by diverse biotic (traditional and new/emerging pests and diseases) and abiotic (erosion, climate change) menaces. These problems could also be of relevance for new geographical areas where olive cultivation is not traditional but is increasingly spreading (i.e., South America, Australia, etc). One of the major constraints for olive cultivation is Verticillium wilt, a vascular disease caused by the soil-borne fungus Verticillium dahliae Kleb. In this review we describe how Verticillium wilt of olive (VWO) has become a major problem for olive cultivation during the last two decades. Similar to other vascular diseases, VWO is difficult to manage and single control measure are mostly ineffective. Therefore, an integrated disease management strategy that fits modern sustainable agriculture criteria must be implemented. Multidisciplinary research efforts and advances to understand this pathosystem and to develop appropriate control measures are summarized. The main conclusion is that a holistic approach is the best strategy to effectively control VWO, integrating biological, chemical, physical, and cultural approaches.     

土壤硝化作用的抑制剂调控及其机理

既要保证氮肥在优质高效农业生产中的促进作用,又要保证农业和环境的可持续发展,如何提高氮肥利用率、减轻氮肥污染成了解决问题的关键.从氮素在土壤中的生物化学转化过程入手,通过抑制剂的施用来调控氮素的转化,减缓硝化过程的进行,是解决该问题的一种有效措施.本文从硝化抑制剂的定义、筛选硝化抑制剂的条件、国内外较受关注的硝化抑制剂品种以及硝化抑制机理等几个方面对目前的研究进展进行综述,并提出目前研究中存在的问题及今后的研究方向.