一株红棕象甲寄生真菌的分离鉴定

为明确一株红棕象甲寄生真菌的归属,采用形态学及分子生物学方法,从产孢表型、分生孢子特征和ITS序列测定等方面对其进行了分析鉴定。结果表明:该菌分生孢子梗粗短,顶端具2～5个瓶状小梗,分生孢子呈长椭圆形或圆柱形,大小为4.8～9.3μm×2.2～3.1μm;ITS通用引物扩增该菌得到了预期的558bp条带,其与金龟子绿僵菌小孢变种的支持率高达100%。因此,将该红棕象甲寄生真菌菌株鉴定为金龟子绿僵菌小孢变种Metarhiziumanisopliaevar.anisopliae。     

武夷菌素对活体微生物农药的影响

本文以武夷菌素为主要对象,以牛津杯抑菌测试法和菌丝生长抑制法观察武夷菌素对几种常见的真菌类活体微生物农药之间的影响。武夷菌素对于真菌孢子的抑制试验结果显示,武夷菌素在高浓度处理下对球孢白僵菌的抑制作用显著大于金龟子绿僵菌,其中对球孢白僵菌的最小抑菌浓度为400 mg/L,对金龟子绿僵菌的最小抑菌浓度为200 mg/L。武夷菌素对绿色木霉、哈茨木霉、淡紫拟青霉菌丝生长率的抑制试验结果显示：武夷菌素100 mg/L浓度对于三种真菌菌丝生长的抑制率分别为64.6%、48.6%、39.2%,进行毒力回归方程计算,数据表明武夷菌素对绿色木霉的EC₅₀为57.13 mg/L,对哈茨木霉的EC₅₀为109.81 mg/L,对淡紫拟青霉的EC₅₀为170.03 mg/L。武夷菌素在防治病害过程中实际用药量约100 mg/L,会对金龟子绿僵菌、球孢白僵菌、绿色木霉、哈茨木霉和淡紫拟青霉产生不同程度的抑制,建议应错开使用。本研究所获得的结果对指导武夷菌素及活体微生物农药的生物防治应用具有重要的意义,为生物防治技术集成提供理论基础。     

绿僵菌与椰甲截脉姬小蜂对椰心叶甲的协同控制作用

在室内条件下,研究了金龟子绿僵菌小孢变种Metarhizium anisopliae var. anisopliae侵染和椰甲截脉姬小蜂Asecodes hispinarum寄生两种生防措施之间的相互影响,并对两种措施协同控制椰心叶甲Brontispa longissima的效果进行了评价。结果表明,绿僵菌菌株HK4对椰甲截脉姬小蜂成虫安全;但绿僵菌侵染使姬小蜂对椰心叶甲的寄生率显著降低。在先接种绿僵菌后接入姬小蜂的情况下,椰甲截脉姬小蜂对椰心叶甲的寄生率仅为10.23%,显著低于其单独寄生的寄生率79.55%;绿僵菌对椰心叶甲的侵染率为96.59%,高于绿僵菌单独处理的侵染率84.09%,但不显著。而在先接蜂后接种绿僵菌的处理中,绿僵菌对椰心叶甲的侵染率仅为69.09%,显著低于绿僵菌单独处理。对椰心叶甲的生测结果显示,先接种绿僵菌再接入姬小蜂、先姬小蜂寄生再接种绿僵菌、同时接种绿僵菌和接入姬小蜂3种处理的校正死亡率分别为100%、100%、98.86%,显著高于绿僵菌单独侵染和姬小蜂单独寄生。     

新农药介绍

中文通用名称:绿僵菌英文通用名称:Metarhizium anisopliae(拉丁文)农药登记名称及商品名:100亿孢子/毫升绿僵菌油悬浮剂(克洛卡)理化性质:该药的有效成分为金龟子绿僵菌的分生孢子。金龟子绿僵菌是由重庆缙山自然保护区黄脊竹蝗僵虫体内分离出的,菌株编号为CQ102。经鉴定该菌株CQ102属于菌物界、丰知菌亚门、丝孢纲、绿僵菌属、金龟子绿僵菌(异名:黄绿绿僵菌)。其菌落特征:在SDA(萨氏葡萄糖)培养基上菌落初期为白色茸状,产孢时灰绿色至橄榄绿色,自菌落中心由里向外长出成丛的绿色分生孢子堆。分生孢子梗单生或聚集或紧密排列,帚状分枝…     

金龟子绿僵菌CQMa117的营养要求与培养特性初探

金龟子绿僵菌大孢变种Metarhizium anisopliae var.major菌株CQMa117是新分离到的一株对天牛有良好杀虫活性的绿僵菌菌株。通过单因素试验,测试不同温度、pH、碳源、氮源及无机盐类对CQMa117菌株生长和产孢的影响,确定了蔗糖、葡萄糖、可溶淀粉、蛋白胨、尿素、硫酸铵以及Cu^2＋、K^＋、Ca^2＋是菌落生长和产孢的最适碳源、氮源和无机盐类;培养基初始pH6.0、培养温度25℃是菌株的最适产孢条件。通过碳源、氮源及无机盐3个较优水平的正交试验,确定菌株最适合的产孢固体培养基为：1000ml固体培养基中加入10.0g蔗糖、2.5g尿素、5.0g酵母膏和0.001%Cu^2＋,可使CQMa117菌株产孢量比基础培养基增加30.2%。     

布氏白僵菌和金龟子绿僵菌两变种的生长性状及其对蛴螬的毒力测定

以蛴螬病原真菌--布氏白僵菌、绿僵菌小孢变种作参照菌,研究了新分离鉴定的绿僵菌大孢变种的生物学特性,测定了不同温度、不同培养基条件下各菌株对蛴螬的致病能力.结果表明：绿僵菌大孢变种与两种参照菌的培养条件接近,最适宜生长的温度为25℃,所试的3种培养基中,最适宜的培养基为PPDA,其次为SDAY;绿僵菌大孢变种在偏低温（10～20℃）的环境下对蛴螬的毒杀能力比布氏白僵菌强,土壤处理和喷雾处理后,累计僵虫率分别达88.23%和76.47%,有很好的田间应用前景.两种真菌的拌土处理效果高于直接喷雾.鉴于绿僵菌Ma1的致病力较强,在生产上可用该菌进行土壤处理,防治蛴螬等地下害虫.     

烟蚜茧蜂载菌菌种与载菌方式筛选

用茵液粘染法和菌粉粘染法分别让4种虫生真菌侵染烟蚜和烟蚜茧蜂,感染球孢白僵菌、攻烟色拟青霉、粉拟青霉和金龟子绿僵菌,8d烟蚜的死亡率分别为100.00%、78.00%～95.00%、90.00%和66.67%,都显著高于对照(1.67%～3.33%);3d烟蚜茧蜂的死亡率分别为79.67%～80.33%、20.00%～26.67%、46.67%和26.67%～60.00%,其中玫烟色拟青霉处理与对照(20.00%～26.67%)无显著差异.综合考虑4种虫生真菌对烟蚜与烟蚜茧蜂的致死作用,玫烟色拟青霉为适宜的载菌菌种.用孢子液浸染僵蚜、孢子粉喷撒僵蚜和孢子粉沾染雌蜂3种方式让烟蚜茧蜂雌蜂载菌,对雌蜂的活动影响不大,但前两种方式雌蜂载孢量(0.755×108～0.785×108个/头)远低于后一种方式(4.535×108～5.293×108个/头),即孢子粉沾染雌蜂法为适宜的载菌方式.雌蜂携带玫烟色拟青霉在室内对烟蚜的致死率可高达86.0%,比非载菌蜂提高了24.3%.     

金龟子绿僵菌对褐飞虱繁殖力的影响

褐飞虱Nilaparvata lugens(St?l)以单食性水稻为主,是亚洲地区重要的水稻害虫之一,繁殖力强的特点是其大面积为害水稻的重要原因.金龟子绿僵菌Metarhizium anisopliae是一种环境友好型的昆虫病原真菌,近年来被广泛用于害虫防治.本研究结果显示8×1010孢子/mL金龟子绿僵菌悬浮剂在实验...     

西瓜种子带菌检测及杀菌剂消毒处理效果

采用离体平皿法对来自新疆等4个省区的14个西瓜品种进行种子带菌检测、分离纯化和鉴定,并测定了7种杀菌剂和1种种衣剂对种子带菌的消毒处理效果。结果表明,种子表面携带的优势菌群主要为青霉属Penicillium spp.、根霉属Rhizopus spp.、曲霉属Aspergillus spp.、交链孢属Alternaria spp.和镰孢属Fusarium spp.;种子内部寄藏真菌主要为青霉属、根霉属和曲霉属;不同品种之间种子表面携带真菌种类差异较大,种子内部寄藏真菌种类差异不明显;种壳带菌率一般高于种仁带菌率。15% FDDF ·霜·福悬浮种衣剂、福美双和代森锰锌对种子带菌消毒效果优于多菌灵、敌磺钠、 FDDF 霉灵、拌种灵和甲霜灵。     

以绿步甲为载体携播绿僵菌对东亚飞蝗的协同控制作用研究

本文研究了金龟子绿僵菌Metarhizium anisopliae侵染和绿步甲Carabus smaragdinus捕食东亚飞蝗Locusta migratoria manilensis两种生防措施之间的相互影响,同时评价了两种生防措施对东亚飞蝗的协同控制作用。结果表明,金龟子绿僵菌对绿步甲安全。投放绿步甲同时喷施绿僵菌处理和投放经绿僵菌剂接种过的绿步甲处理对东亚飞蝗的捕食率为61.23%和64.19%,侵染率分别为75.34%,70.85%,校正致死率分别达83.33%和100%,均显著高于绿僵菌单剂侵染和绿步甲单独捕食处理。本文证明了绿步甲携播绿僵菌控制害虫的可行性与可持续性,为实现将绿步甲与绿僵菌联合控制害虫提供依据。     

松墨天牛林间防治试验

松墨天牛[Monochamus alternatus(Hope)]是松材线虫病的主要传播媒介,又是马尾松、黑松、雪松、落叶松、云南松等松类植物的重要害虫。为了控制虫灾探讨有效防治技术,特进行噻虫啉、绿僵菌防治松墨天牛的试验。结果表明:应用噻虫啉和绿僵菌无纺布菌条林间防治松墨天牛均有良好的防治效果,从维护物种多样性和森林健康的角度来看,采用绿僵菌无纺布菌条防治松墨天牛具有更好的发展前景。     

北京地区主栽西瓜品种种子携带真菌检测及鉴定

用离体平皿法对北京西瓜产区主栽的11个西瓜品种进行种子带菌检测、分离纯化和形态学、ITS序列比对,确定其属或种地位。结果表明:不同品种所带真菌种类有差异,种子表面携带的优势菌群主要为曲霉属Aspergillus spp.、青霉属Penicilliumspp.、链格孢属Alternariaspp.和镰刀菌属Fusariumspp.;种子内部寄藏真菌主要为青霉属、根霉属Rhizopus spp.和曲霉属。种子外部检出的主要病原菌有镰刀菌属的F.verticillioides,F.proliferatum及茎点霉Phomasp.;种子内部检出的病原菌有F.verticillioides和F.oxysporum。不同品种间种子表面携带真菌量与种子内部携带真菌率差异显著,但种子外部带菌量和内部种仁带菌率之间无显著相关性。本研究对开展西瓜种子处理研究有借鉴意义。     

The use of entomogenous fungi for pest control and the role of toxins in pathogenesis

Fungi have been suggested as agents for the biological control of insects for over a century, but their use remains extremely limited. This paper examines the biology of entomogenous fungi, highlighting their need for moisture, and reviews studies on the Entomophthoraceae, Beauveria bassiana, Beauveria brongniartii, Metarhizium anisopliae and Verticillium lecanii. It is suggested that current studies should be directed towards the control of pests living in humid micro-climates and that moisture-retaining formulations should be developed to reduce the reliance of fungi on moisture. Many entomogenous fungi produce insecticidal toxins in submerged culture and these compounds are of interest as a source of new toxophores. The most extensively studied toxins are the cyclic depsipeptides from M. anisopliae, termed destruxins, and their possible role in pathogenesis is discussed. Beauveria bassiana also produces the cyclic peptides termed beauvericin, beauverolides, and bassianolide. Toxins produced by V. lecanii, and the Entomophthoraceae are also described.     

Occurrence of fungal pathogens of carrots on wooden boxes used for storage

Infested wooden boxes, previously used for carrot storage, were sampled in four commercial carrot production farms in Bradford Marsh, Ontario, and screened for fungal occurrence. At least 128 and 465 fungal isolates were recovered from these boxes in 2001 and 2002, respectively, and were classified into 10 taxonomic groups, including Alternaria spp., Aspergillus spp., Botrytis cinerea , Fusarium spp., Mucor spp., Penicillium spp., Rhizoctonia carotae , Rhizopus spp., Sclerotinia sclerotiorum and Trichoderma spp. A subsample of 27 putative pathogenic isolates was further tested for the ability to cause disease on carrots and to colonize wood surfaces under growth room and cold storage conditions. Approximately 60% of the taxa growing on wood caused lesions upon contact with intact carrots in cold storage. Isolates of S. sclerotiorum , B. cinerea and R. carotae caused the most severe diseases, developed most extensively on wooden surfaces in cold storage, and represented 12% of the recovered fungi. Isolates of Alternaria spp., Aspergillus spp., Fusarium spp., Mucor spp., Penicillium spp., Rhizopus spp. and Trichoderma spp. caused negligible or no disease on carrots and represented 88% of recovered fungi. Several of these fungi, however, showed potential to colonize wooden surfaces and cause disease on sliced carrots. This study suggests that pathogenic inocula occurring on used wooden boxes can initiate disease upon contact with healthy carrots and reusing infested boxes can affect carrots in storage.     

大蒜鳞茎腐烂病的病原鉴定

从江苏太仓产蒜区及南京周边市场采集的病蒜上分离到 5株细菌和 3种真菌 ,经柯赫氏法则验证 ,均确定为大蒜鳞茎腐烂的病原菌。经细菌形态特征观察和生理生化性状测定结果表明 :g W、g 1属芽孢杆菌 (Bacillus spp .) ;g Y、g 2为欧文氏菌 (Erwinia spp .) ;g 3属红球菌 (Rhodococcu ssp .)。真菌的形态特征观察鉴定结果表明 :3株真菌F1、F2、F3分别属于黄青霉 (Penicillium chrysogenum Thom)、黑曲霉 (Aspergillus niger van Tiegh)和尖胞镰刀菌 (Fusarium oxysporum)     

Laboratory evaluation of temperature effects on the germination and growth of entomopathogenic fungi and on their pathogenicity to two aphid species

As part of an approach to select potential mycoinsecticides for aphid biocontrol, we investigated the effects of temperature on the growth, germination and pathogenicity of some hyphomycete fungi. Commercially available mycoinsecticides (based on Beauveria bassiana (Balsamo) Vuillemin and Verticillium lecanii (Zimmermann) Viegas) and other isolates of B bassiana, V lecanii, Metarhizium anisopliae (Metschnikoff) Sorokin and Paecilomyces fumosoroseus (Wize) Brown & Smith were evaluated. The rate of in vitro conidial germination of all isolates was slower at 10 and 15 degrees C than at 20 and 25 degrees C. Similarly, in vitro growth of most isolates was adversely affected at 10 and 15 degrees C. The greatest reduction at 10 degrees C in rates of conidial germination and colony growth, compared with other temperatures, was for M anisopliae isolates. Germination of V lecanii (isolate HRI 1.72) was fastest at 10 degrees C compared with the other fungi. It was also the most pathogenic of three isolates tested against Aphis fabae Scopoli and Myzus persicae Sulzer at 10, 18 and 23 degrees C. Generally, A fabae was more susceptible than M persicae to infection by the fungal isolates tested. A significant interaction between aphid species and temperature indicated that the pathogenic nature of an isolate was dependent not only on the target aphid species but also the temperature conditions of the bioassay. The series of studies, detailed above, allowed a temperature profile to be formed for the different isolates. Verticillium lecanii isolate HRI 1.72 (commercialised as Vertalec) was the most promising isolate selected from results of the series of experiments. Temperature profiles in conjunction with infectivity assays can be useful in selecting appropriate isolates for a particular thermal environment.     

释放花绒寄甲和设置诱木防治松褐天牛对松材线虫病的控制作用研究

松材线虫是我国林业重大外来有害生物,松褐天牛是传播松材线虫病的主要媒介昆虫。本研究通过在松材线虫病疫区布设诱木引诱松褐天牛成虫集中产卵,翌年在下一代松褐天牛成虫羽化出孔前清理林中诱木和枯死木,以及在诱木布设区同时释放寄生性天敌花绒寄甲等措施,探讨对松材线虫病的控制作用。研究结果显示,林间设置诱木和释放天敌的样地内枯死木和衰弱木数量较对照显著下降,防治效果分别为71．27％和90．25％。防治后诱木处理区和释放天敌的样地内携带松材线虫的病木数量以及松褐天牛的虫口密度也显著降低。释放天敌的样地和未释放天敌的样地内松褐天牛的寄生率分别为38．34％和3．92％,二者差异明显。室内人工接种天敌的测定结果表明,天敌与害虫数量比例为1：1～4：1的寄生率为12．5％～40％,不同比例的处理寄生率无显著差异。每根木段释放10头花绒寄甲成虫比释放4头成虫的处理松褐天牛的寄生率明显要高,分别为19．45％和4．11％。表明天敌在林间对松褐天牛种群起到重要的控制作用,从而阻止天牛对松材线虫病的扩散传播。     

Biological control of Fusarium oxysporum f. sp. lycopersici

Fungi known to produce lytic enzymes were used in an attempt to control wilt of tomato caused by Fusarium oxysporum f. sp. lycopersici (FOL). Some of the fungal species (Penicillium oxalicum, Penicillium purpurogenum and Aspergillus nidulans) damaged hyphae of FOL in vitro and reduced the numbers of microconidia in the soil. Treatments with fungi did not result in a reduction in either chlamydospores of FOL in soil or populations of FOL in the rhizosphere of tomato. P. oxalicum was the most effective agent of biocontrol, and it reduced disease severity in both non-autoclaved (20% decrease) and sterile soil. In sterile soil, P. oxalicum reduced disease with different levels of severity (27% decrease at high levels and 50% decrease at low levels). Disease control by A. nidulans and P purpurogenum was only achieved when disease severity was low in sterile soil (55% and 45%, respectively).     

松褐天牛疫木隔离结合人工释放管氏肿腿蜂防治松材线虫病

为提高天敌昆虫寄生松褐天牛以此控制松材线虫病的效果,本研究采用松褐天牛疫木就地隔离,同时加上人工助放管氏肿腿蜂的方法,开展了控制松材线虫病的试验。结果表明：管氏肿腿蜂对松褐天牛低龄幼虫的致死率最高达68．50％,对中老龄幼虫的致死率为44．58％。3月和4月释放,松褐天牛死亡率分别为57．11％和65．64％,而5月份释放幼虫死亡率只有14．57％。将疫木劈为4开的情况下时,天牛死亡率最高,达71．33％。单边放蜂,松褐天牛的死亡率最高达67．18％。铁丝网、渔网和聚丙烯布隔离疫木对松材线虫病的发生都有较好的控制效果,其中铁丝网隔离后,健康松树死亡率下降到2．5％,渔网和聚丙烯布隔离后,松树死亡率为12％,均显著低于对照的80％。表明隔离松疫木加上施放管氏肿腿蜂能有效控制松材线虫病流行危害。     

德国小蠊肠道细菌抗真菌的初步研究

初步研究表明来自德国小蠊Blattella gemmnica Linnaeus肠道的细菌能产生广谱的抗真菌活性物质，对白色念珠菌Candlida albican、深红酵母Rhodotorula rubra（Demme）Lodder、丝核菌Rhixoctonia solani Huhn、黄萎轮枝孢菌Verticillium alboatrum Reinke、镰刀菌Fusarium solani（mart．）Sacc．、黄曲霉Aspergillus flavus Link、黑曲霉Aspergillus，niger Van Tieghem都有明显的抑制作用。推测蜚蠊肠道细菌有助其抵抗病原真菌，同时也为开发用于医药、农业的广谱抗真菌的活性物质提供新途径。