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玉米弯孢菌毒素理化性质及致病机理的研究 总被引：5，自引：0，他引：5
对玉米弯孢菌产生毒素的理化性质和致病机理进行了初步研究。结果表明:毒素的化学成分包括蛋白质和可溶性糖;毒素对不同玉米自交系种子萌发和叶片致萎程度的影响有明显差异,研究结果与弯孢菌对不同抗性自交系的致病能力基本一致。 相似文献
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利用鉴别寄主技术对黑龙江省、吉林省、辽宁省和河北省玉米弯孢叶斑病菌的生理分化进行研究。结果表明,20个菌株的致病性分为5种类型,其中强和中等致病类型主要分布在辽宁省的瓦房店、吉林省的公主岭和河北省的保定市。 相似文献
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对吉林省玉米弯孢菌叶斑病的发生和防治几个问题进行试验研究。结果表明:室内保存1～3年的病叶、当年室外越冬的病叶均具有产孢能力;玉米生育期对弯孢菌侵染概率有明显的影响,生育前期侵染概率高,抗侵染力低,生育后期侵染概率低,抗侵染力强;施用氮肥、磷肥对玉米弯孢菌侵染概率影响不明显,而钾肥能降低侵染概率。对生产中一些玉米品种、自交系进行抗病性鉴定,如吉玉106、CM1、济单7号、吉846、5002表现抗性较好。筛选出对防治弯孢菌叶斑病有效的药剂:甲基托布津防效最高,可达91.59%;其次是炭疽福美、速克灵,防效也分别达88.37%和82.98%;代森锰锌的防效为78.37%。 相似文献
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玉米弯孢菌叶斑病菌致病性遗传变异 总被引：6，自引：1，他引：6
通过对采集国内各地的玉米弯孢叶斑病菌接种玉米不同品种,做寄主-病菌互作试验,结果发现,病菌菌株和玉米品种在地域上存在一定的相关性,本地菌株对当地主推玉米品种具有一定的致病专化性,证明病菌致病性遗传和分化与玉米品种遗传背景有关。 相似文献
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玉米尾孢菌,弯孢菌叶斑病发病规律初探 总被引：1，自引：0，他引：1
尾孢菌 (Ｃｅｒｃｏｓｐｏｒａｍａｙｄｉｓ)和弯孢菌(Ｃｕｒｖｕｌａｒｉａｌｕｎａｔａ(Ｗａｋｋｅｒ)Ｂｏｅｄｉｊｎ)叶斑病均为发生在玉米叶片上的病害。 1996年辽宁省部分地区严重发生玉米弯孢菌斑病(拟眼斑病 )和尾孢菌斑病 (灰斑病 ) ;1997年作物生育期间高温多湿 ,庄河地区玉米普遍发病 ,其中沈单 7号、掖单 13号、东试 7号等品种表现较为严重 ;1998年发病比上一年稍轻 ,玉米叶斑病主要表现为拟眼斑病和灰斑病 ,发生也较重。拟眼斑病和灰斑病可使玉米减产 10 %～ 2 0 %,个别严重地块减产可达2 5 %～ 30 %,所以研究玉米尾孢菌、弯孢… 相似文献
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Antagonistic interactions between honey bee bacterial symbionts and implications for disease 总被引：1，自引：0，他引：1
Background
Honey bees, Apis mellifera, face many parasites and pathogens and consequently rely on a diverse set of individual and group-level defenses to prevent disease. One route by which honey bees and other insects might combat disease is through the shielding effects of their microbial symbionts. Bees carry a diverse assemblage of bacteria, very few of which appear to be pathogenic. Here we explore the inhibitory effects of these resident bacteria against the primary bacterial pathogen of honey bees, Paenibacillus larvae. 相似文献12.
对河西走廊制种玉米生育中后期叶部真菌病害进行田间调查,并将采集到的标本进行组织分离、病原鉴定和致病性测定。结果表明,引起制种玉米生育中后期叶部真菌病害的植物病原有13种,其中由Curvulairia lunata(Wakke)Boed病原引起的玉米弯孢菌叶斑病是玉米叶部的一种新病害,在田间发病率较高,病情指数较大,危害十分严重;由Exserohilum turcicum(Pass.)Leonard et Suggs和Bipolaris maydis(Nishik.et Miyabe)Shoemaker病原引起的大斑病和小斑病是玉米生育中后期叶部发生的主要真菌病害;Physoderma maydis Miyabe和Fusarium subglutinans(Wollenwe.et Reinking)P.E.Nelson et al病原引起的褐斑病和顶腐病有加重发生的趋势;Puccinia sorghi Schw引起的普通锈病在局部区域的一些品种和组合上发病较为严重;其他叶部病害零星发生,对制种玉米正常的生长发育影响较小,一般不会造成流行为害。 相似文献
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The survival of pathogenic and spoilage micro‐organisms in soil and on grass fertilized with spiked anaerobic digestion residue (ADR) was investigated in a climate chamber during periods of up to 56 d. In addition, the survival of these organisms over time was investigated during ensiling of grass at 390 g dry matter (DM) kg?1 or 610 g DM kg?1. Micro‐organisms included in these studies were: Clostridium tyrobutyricum, Salmonella serotype Typhimurium, Listeria monocytogenes, Campylobacter jejuni, Escherichia coli, Talaromyces emersonii, Byssochlamys nivea, Porcine parvovirus and Swine vesicular disease virus. Soil and grass still contained high numbers of E. coli, Cl. tyrobutyricum and T. emersonii (1·9–5·4 log10) 49 and 56 d after fertilization with spiked ADR. Listeria monocytogenes and S. Typhimurium were generally found in the samples. This indicates that, within this time span, there is a risk of silage contamination by bacteria, moulds and viruses present in ADR spread on grassland. An increase in DM content of the crop decreased its ensilability as measured by pH and short‐chain fatty acid content. However, no clear differences were found in survival of pathogenic and spoilage micro‐organisms between the two silages with different DM contents, regardless of storage time. The lack of moisture and oxygen was probably sufficient to cause the reduction in vegetative bacteria in the 610 g DM kg?1 silage. However, bacterial and fungal spores and the viruses studied were not significantly inactivated by ensiling at these high DM contents and could, therefore, pose a health risk to farm animals fed on the silage if present in ADR applied to crops prior to ensilage. 相似文献
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为明确不同轮作模式对小麦赤霉病菌种群结构和毒素化学型影响,于2019-2020两个小麦生长季,从湖北襄阳、枣阳长期稻-麦轮作和长期玉-麦轮作田分别采集小麦赤霉病穗,采用组织病理学分离镰孢菌单孢堆菌株,并对其采用特异性引物进行致病种和毒素化学型分子鉴定。结果表明,从采集样品中共分离获得191个镰孢菌单孢堆菌株;亚洲镰孢菌F.asiaticum为该区稻-麦轮作田优势种,占稻-麦轮作田分离菌株总数的93.0%,主要产生3-AcDON;禾谷镰孢菌F.graminearum为玉-麦轮作田优势种,占玉-麦轮作田分离菌株总数的62.9%,既可能产生15-AcDON,又可能产生3-AcDON;191个菌株中仅有11个菌株产生NIV,占比5.8%。以上结果揭示,小麦赤霉病镰孢菌致病种和毒素化学型组成与轮作模式密切相关,镰孢菌优势致病种和毒素的类型可能与镰孢菌对小麦前茬作物的偏好性有关。 相似文献
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以获得的野生型和CzVelB敲除突变体菌株为供试菌株,分别对其进行生物学及致病力测定,在此基础上分析毒素和细胞壁降解酶的活性。结果表明,与野生型相比,敲除CzVelB后菌丝生长速率及颜色无明显差异,但产孢量下降56.6%,且孢子萌发率下降,萌发过程滞后1 h。致病性分析发现,敲除CzVelB后菌株致病性明显下降,病情指数、病斑大小,突变体均低于野生型。分析毒素对叶片的致病性发现,突变体所产生的毒素低于野生型产生的毒素。敲除突变体菌株ΔCzVelB及野生型菌株在活体内外均能产生5种细胞壁降解酶,其中敲除CzVelB后,5种离体病原菌细胞壁降解酶活性明显下降。分析侵染过程中5种细胞壁降解酶发现,CzVelB主要通过影响CX和PMG在接种前期12 h内起重要作用;在接种后期(72～96 h),CzVelB主要通过影响PGTE的活性调控玉蜀黍尾孢菌致病力。 相似文献
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Summary The highlands of South America are the probable geographic origin for the potato gangrene fungusPhoma exigua var.foveata (Foister) Boerema which was found parasitizing plants ofChenopodium quinoa in the Altiplano area of Peru. In vitro studies showed no dissimilarities between it and the antibiotic ‘E’ producing virulent
European isolates ofP. exigua var.foveata. It is as pathogenic to potatoes as the virulent European isolates but onC. quinoa andC. album it is more pathogenic than the European isolates. So far the fungus has not been found on potato tubers in South America
and the reasons why gangrene problems have not arisen there are discussed. 相似文献
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东北地区玉米丝黑穗病菌类型分化的初步研究 总被引：2，自引：1，他引：1
通过人工接种的方法,利用7个对玉米丝黑穗病菌抗、感差异明显的自交系作为鉴别寄主,将其划分为4个鉴别寄主池。利用4个鉴别寄主池对东北三省的11个地区的玉米丝黑穗病菌类型进行分析。结果发现,不同来源的玉米丝黑穗病原菌对不同材料的致病性不同,可能存在5种玉米丝黑穗病原菌类型,即高致病的哈尔滨丝黑穗病原菌Ⅰ型;绥化和大庆地区的丝黑穗病原菌Ⅱ型;辽宁省农科院和密山地区的丝黑穗病原菌Ⅲ型;吉林省的白城、范家屯和双城的丝黑穗病原菌Ⅳ型;四平、佳木斯和海伦地区的丝黑穗病原菌Ⅴ型。同时,还发现高粱丝黑穗病菌对玉米鉴别寄主自交系具有一定的侵染性。 相似文献
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《Journal of Crop Improvement》2013,27(1):67-79
Abstract Ten different isolates of Macrophomina phaseolina from cluster bean (Cyamopsis tetragonoloba) selected on the basis of wide geographical distance and potassium chlorate sensitivity, showed remarkable variation in virulence on the susceptible cluster bean genotype, FS 277. Four different host inoculation techniques were employed for resistance screening of six elite cluster bean genotypes under artificial infection conditions using the most pathogenic isolate, MP-6D. The symptoms induced in the plant tissues from seedling to maturity following artificial inoculation clearly simulated lesions produced under natural conditions. Both greenhouse and field experiments demonstrated significant differences in all parameters-plant weight, plant death, root lesion length and stem lesion length-in all the genotypes tested from seedling stage to pod set. The host inoculation methods described in this study might be useful for screening and analysis of crop varieties' resistance to various other disease infestations. The present investigation involved evaluation of pathogenicity of isolates of M. phaseolina as well as a critical examination of occurrence of resistance to charcoal rot in selected cluster bean genotypes. This is the first report on cluster bean resistance to M. phaseolina. 相似文献