应用虫生真菌防治烟粉虱的现状

烟粉虱Bemisia tabaci属世界性分布的大害虫.在一定条件下虫生真菌是控制烟粉虱种群的最有效天敌.本文就几种常见虫生真菌:蜡蚧轮枝菌Verticilliumlecanii、座壳孢Aschersoniaspp.、玫烟色拟青霉Paecilomycesfumosoroseus、球孢白僵菌Beauveria bassiana等防治烟粉虱的应用现状以及它们与其它天敌的关系进行了综述,以期对烟粉虱虫生真菌的合理利用提供参考.     

虫生真菌分子致病机理及基因工程改造研究进展

虫生真菌侵染寄主昆虫的复杂过程可分为体表附着、体壁穿透及体内定殖和致死等不同阶段。近年来, 以金龟子绿僵菌(Metarhizium anisopliae)和球孢白僵菌(Beauveria bassiana)为代表的基因功能研究取得了长足的进展, 从不同角度阐明了虫生真菌的分子致病机理; 同时, 基因工程技术的应用为昆虫病原真菌的遗传改良和选育高毒力杀虫菌株开辟了新的途径。对近年来昆虫病原真菌侵染寄主的分子对策及基因工程改造的研究进展进行了综述, 并就进一步研究虫生真菌的毒力基因及功能进行了探讨。     

利用虫生真菌生物防治柑橘木虱的研究进展

柑橘木虱是柑橘黄龙病的重要传播虫媒。目前对柑橘黄龙病的防治尚缺有效的药剂和抗病品种,加强对柑橘木虱的防治,对控制柑橘黄龙病的蔓延具有重要意义。目前防治柑橘木虱多采用化学防治,杀虫剂的频繁使用造成了农药残留、环境污染、生物多样性被破坏和害虫产生抗药性等诸多问题,生物防治以其高效、低毒、低残留、不易产生抗药性等优点逐渐受到重视。昆虫病原真菌能侵入昆虫寄主体内,导致昆虫发病死亡,具有良好的病害流行潜力及生产应用便利性,利用昆虫病原真菌防治柑橘木虱具有广阔的发展空间。本文总结了用于柑橘木虱生物防治的虫生真菌种类,重点介绍了国内外利用球孢白僵菌、玫烟色棒束孢、淡紫紫孢菌、宛氏拟青霉、蜡蚧菌等虫生真菌在防治柑橘木虱中的应用,并对虫生真菌防治柑橘木虱的发展前景进行了展望,以期为柑橘黄龙病的防控提供借鉴。     

虫生真菌分子致病机理及基因工程改造研究进展

虫生真菌侵染寄主昆虫的复杂过程可分为体表附着、体壁穿透及体内定殖和致死等不同阶段.近年来,以金龟子绿僵茵(Metarhizium anisopliae)和球孢白僵菌(Beauveria bassiana)为代表的基因功能研究取得了长足的进展,从不同角度阐明了虫生真菌的分子致病机理;同时,基因工程技术的应用为昆虫病原真菌的遗传改良和选育高毒力杀虫菌株开辟了新的途径.对近年来昆虫病原真菌侵染寄主的分子对策及基因工程改造的研究进展进行了综述,并就进一步研究虫生真菌的毒力基因及功能进行了探讨.     

西花蓟马高毒力虫生真菌筛选及其生防应用潜力的研究进展

西花蓟马是一种外来入侵的世界性害虫,对农林业危害巨大。查阅国内外相关文献,综述了当前防治西花蓟马的虫生真菌的种类、高毒力菌株的筛选及防治现状。现已知西花蓟马的寄生病原真菌有5种,包括蜡蚧轮枝菌(半知菌:丝孢目)、球孢白僵菌(半知菌:丝孢目)、金龟子绿僵菌(半知菌:丝孢目)、玫烟色棒束孢(半知菌:束梗孢目)和小孢新接霉。其中,球孢白僵菌、金龟子绿僵菌在西花蓟马的生物防治中应用最广,具有良好的开发应用潜力,部分防效好的虫生真菌已申请专利及实现工厂化生产。     

浅谈虫生真菌致病机制及昆虫活体防卫功能

昆虫真菌学是一门新兴学科，其中关于虫生真菌致病及昆虫抗病机理的研究，是一个活跃的领域，已深入至分子水平。本做一扼要介绍。     

虫生真菌育种工作研究进展

虫生真菌在害虫的生物防治中有着极其重要的作用,在植物病害和杂草的生物防治、保健品、医药和化妆品等领域的开发应用上也具有很大的潜力.目前虫生真菌的育种工作主要采用自然选育、人工诱变、准性生殖、原生质体技术、基因工程技术等方法获得优良菌株.对虫生真菌的育种方法及其应用进展进行了综述,同时评述了各种育种方法的优缺点,分析了今后虫生真菌的育种方向.     

虫生真菌研究与应用的发展与机遇 ——2012年虫生真菌专刊序言

我国从事虫生真菌基础及应用研究的人员众多,各方面均取得了重要的研究成果。2012年“虫生真菌专刊”收集了国内关于虫生真菌资源、基因克隆及活性成分代谢等方面的最新研究进展。进一步的基础研究,应加强致病基因功能和真菌-昆虫分子相互作用等研究,以提高真菌杀虫剂或药用虫生真菌的应用效率。     

骨转换生化指标的研究进展及选择依据

骨转化生化标志物的检测以其简便、快捷、无创等优点,在流行病学研究、长期跟踪监测、骨折风险评估等芳面独具优势.与骨影像学和骨形态计量学观察相比,其反映的是骨细胞活性的实时信息,因此是评价骨转换状况、观察药物早期疗效的重要手段.     

辽宁省虫生真菌的2个新记录种

报道了在辽宁省丹东市白石砬子国家自然保护区采集到的2个辽宁省新记录种,即虫草科(Cordycip-itaceae)的下垂虫草(Cordyceps nutans Pat.)和日本棒束孢(1sariajaponica Yusuda),并描述了其形态特征和生境分布.     

A Bioassay for Determining Pathogenicity of Entomogenous Fungi on Whiteflies

A simple and effective laboratory bioassay method for determining the pathogenicity of entomogenous fungi to whiteflies is presented. The bioassay is based on characterization of the growth rate and development of entomogenous fungi on fourth instar nymphs of the silverleaf whitefly (SLWF), Bemisia argentifolii (Bemisia tabaci, Strain B), and is useful in determining the effects of environmental factors (e.g., temperature and humidity) and additives (e.g., surfactants, adjuvants, and pesticides) on the development of entomogenous fungi. Such information can provide a better understanding of the influence of these factors on the performance of entomogenous fungi when tested under field conditions. The bioassay has been successfully implemented for the evaluation of the pathogenicity of Paecilomyces fumosoroseus, Verticillium lecanii, and Beauveria bassiana against fourth instar nymphs of SLWF. It has the potential to be useful as a screening tool for determining pathogenicity of new fungal isolates and for the standardization and quality control of commercial fungal preparations for viability and virulence against insect pests before they are used far field applications.     

虫生真菌玫烟色棒束孢Pf9606抗逆性的研究

采用凹玻片悬滴法测定了玫烟色棒束孢在高温、紫外照射、紫外保护剂和杀菌剂等逆境胁迫下分生孢子的存活率。结果表明:玫烟色棒束孢Pf9606分生孢子在36～45 ℃高温下连续处理24 h后,该菌孢子几乎不能存活;36～45 ℃短时高温处理后,随温度的升高和处理时间的延长,孢子存活率明显降低;随紫外照射时间的延长,玫烟色棒束孢孢子存活率明显降低,当紫外照射50 s时,孢子存活率为55.33%,当照射时间延长为180 s时,孢子不能存活;不同浓度的抗坏血酸和高浓度的荧光素钠可提高玫烟色棒束孢抗紫外照射能力,抗坏血酸的理想浓度为0.2 mg/mL,荧光素钠的理想浓度为0.9 mg/mL,而不同浓度的刚果红和氧化锌对玫烟色棒束孢没有保护作用;玫烟色棒束孢与杀菌剂72%农用硫酸链霉素、70%代森联和58%甲霜灵锰锌混用后,对该菌孢子存活影响较小,不同浓度下孢子存活率均达85%以上,而常规浓度的氟吗·锰锌对玫烟色棒束孢孢子存活有较强的抑制作用。     

Biochemical and Immunochemical Studies of Fungi

Crude mannans extracted from Candida albicans and Saccharomyces cerevisiae by autoclaving yeast cells in citrate buffer (pH 7.0) according to Peat's method, were fractionated repeatedly by column chromatography on DEAE-Sephadex, acetate form, yielding neutral and acidic mannans. The former fraction showed a single peak by boundary electrophoresis and ultracentrifugal analysis, while the latter contained small amounts of phosphorus and protein. Using purified mannans as controls, various serological experiments were carried out with mannan antigens extracted from C. albicans with 45% phenol water and with 3% NaOH. No remarkable differences were observed in the antigenic activity of 4 mannan antigens from C. albicans, and the purified mannan exhibited very high antigenic activity. It was found that the mannan of S. cerevisiae was antigenically less specific than that of C. albicans mannan. The difference in serological specificity between mannans of both species may reflect not only differences in mannopyranose linkages but differences in the structure of the macromolecules.     

Immunochemical and Biochemical Studies of Fungi

Polysaccharides were separated from mycelia and culture filtrates of the filamentous fungi Aspergillus niger and Penicillium chrysogenum, and purified by column chromatography on Sephadex G-50, DEAE- and CM-cellulose, successively. No nitrogen and phosphorus were detected in the polymer, and the sugar components were observed to be galactose and mannose. The polysaccharides were confirmed to be galactomannans which were easily hydrolyzed by weak acid, liberating galactofuranose and oligosugar in dialyzable fractions.     

分子标记及其在鸟类分子生态学研究中的应用

分子生态学是一门相当新的分支学科,从前人的研究工作来看,分子标记在这个学科中应用非常广泛,本文描述了RFLP、RAPD、MinisatelliteDNA,MicrosatelliteDNA和AFLP这5个分子标记的优缺点及其在鸟类分子生态学中的应用和研究概况。     

On the Immunochemical and Biochemical Studies of Fungi

The nature of the cross reaction of the mycelial mannan of Trichophyton rubrum and galactomannan isolated from the culture medium of Aspergillus fumigatus with antisera of Saccharomyces cerevisiae and Candida albicans is described. Cross-reactivity of polysaccharides of both T. rubrum and A. fumigatus was weak with antisera of C. albicans and S. cerevisiae, but the galactomannan of A. fumigatus showed slightly stronger activity than the mannan of T. rubrum which possesses more closely related chemical structure of the mannans of S. cerevisiae and C. albicans.     

胚珠发育的分子基础

胚珠作为胚囊的携带者,在植物的生殖过程中起重要作用。胚珠是种子的前身,它在受精后发育成种子。近年来通过诱变已创造出一些胚珠和胚囊发育异常的突变体,如 sin1, bell, ovm2, ovm3。这几个突变体的表现型不但是珠被发育异常,而且胚囊不能形成或发育异常,最终结果是雌性不育。同时,已分别从蝶兰和矮牵牛的胚珠中分离出一批胚珠发育特异的基因,其中有关MADS Box基因在胚珠形成和发育中的作用研究得比较清楚,基因转化工作证实胚珠的分化和形成受一类新的MADS Box基因控制。     

Diversity of Physiological and Biochemical Characters of Microdochium Fungi

The biological characterization of Microdochium majus, M. nivale, and M. seminicola strains with wide geographical origins showed the diversity of their pathogenic properties and metabolite compounds, allowing them to exist in their habitats. Significant differences in the ability of Microdochium fungi to cause lesions on wheat and oat leaves were found. The intensity of symptoms depended on the species and substrate origin of the strains. On average M. seminicola strains were able to cause less leaf necrosis than M. majus and M. nivale. The volatile organic compound (VOC) profile of Microdochium fungi included 29 putative fungal metabolites. The spectrum of the identified VOCs in M. seminicola strains was much richer than that in M. majus and M. nivale strains. In addition, the strains of M. seminicola emitted at least six sesquiterpenes. Mycotoxin analysis by HPLC/MS/MS revealed that the analyzed Microdochium strains did not produce any toxic metabolites typically produced by filamentous fungi.