共查询到19条相似文献,搜索用时 93 毫秒
1.
ScleortiumcepivorumBerk.是引起洋葱白腐病的病原真菌,大部分测试的菌株含有dsRNA片段,这些dsRNA片段被称为真菌病毒。经琼脂糖凝胶电泳分析,在不同分离株之间或同一分离株不同提取物之间dsRNA带的数量和位置有很大的变化。ScQ-4菌株菌丝生长缓慢,致病力明显低于其他菌株。采用蔗糖密度梯度离心法证实和确定ScQ-4菌株中dsRNA片段所处的亚细胞位置,结果表明这些dsRNA片段与其寄主线粒体共同纯化,因此它们可能存在于寄主线粒体中,属于线粒体病毒。在营养相容性菌株之间这些dsRNA片段可通过菌丝融合进行传播,获得dsRNA片段的受体菌株的致病力明显降低,这对SclerotiumcepivorumBer.k进行生物防治提供了可能性。 相似文献
2.
Scleortium cepivorum Berk.是引起洋葱白腐病的病原真菌,大部分测试的菌株含有dsRNA片段,这些dsRNA片段被称为真菌病毒。经琼脂糖凝胶电泳分析,在不同分离株之间或同一分离株不同提取物之间dsRNA带的数量和位置有很大的变化。ScQ-4菌株菌丝生长缓慢,致病力明显低于其他菌株。采用蔗糖密度梯度离心法证实和确定ScQ-4菌株中dsRNA片段所处的亚细胞位置,结果表明这些dsRNA片段与其寄主线粒体共同纯化,因此它们可能存在于寄主线粒体中,属于线粒体病毒。在营养相容性菌株之间这些dsRNA片段可通过菌丝融合进行传播,获得dsRNA片段的受体菌株的致病力明显降低,这对Sclerotium cepivorum Ber.k进行生物防治提供了可能性。 相似文献
3.
自从1962年Hollings在栽培蘑菇(Agaricus bisporus)中发现第一例真菌病毒以来,迄今已在100多种真菌中发现了病毒,多数含双链RNA基因组。1972年Bozarth报道在R.solani中发现病毒,但未报道该病毒的理化性质。1975年Finlker在R.solani的一个强致病力菌株中分离到双链RNA病毒,它含3个组分dsRNA。 相似文献
4.
棉立枯丝核菌的dsRNA与致病力的研究 总被引:3,自引:0,他引:3
对我国北方棉立枯丝核菌(Rhizoctonia solani)的18个分离物进行了dsRNA的检测和致病力比较,可见:(1)dsRNA以高频度(16/18)存在于各分离中;(2)各分离物的dsRNA有明显不同的电泳图谱,有1—8个片段,分子量自0.94—4.8×106道尔顿;(3)同地区土壤中分离物常有相同的dsRNA片段;(4)以弱致病力分离物BALr-2的[r-32P]ATP末端标记dsRNA为探针与16个分离物dsRNA进行分子杂交,只有3个分离物有强的同源性,Northern转移杂交表明同源核苷酸在1.15×106的片段;(5)变性电泳示丝核菌的dsRNA泳动率有减慢现象,从而提出环状dsRNA的可能。 相似文献
5.
【目的】评价5种不同脱毒方法对金针菇(Flammulina velutipes)菌株的脱毒效果,筛选出脱毒率高和脱毒后金针菇菌株菌丝生长速度、生物量、漆酶活力等性状改善明显的脱毒方法。【方法】以栽培金针菇菌株F-4889为研究材料,从菌丝体中提取大小约2.0 kb的病毒dsRNA,经RT-PCR鉴定该病毒为金针菇褐化病毒(FvBV)。采用菌丝尖端分离、原基组织分离、原生质体单核化、有性生殖和核迁移5种脱毒方法对金针菇菌株进行脱毒处理,利用dsRNA技术和RT-PCR检测脱毒效果。【结果】菌丝尖端分离脱毒后得到1株脱毒菌株;原基组织分离法未能脱毒;原生质体单核化脱毒法得到3株脱毒单核菌株和2株原单杂交脱毒菌株;有性生殖脱毒法获得脱毒孢子单核菌株23株和单孢杂交脱毒菌株8株;核迁移脱毒后得到5株核迁移脱毒菌株。脱毒率依次为25.0%、0、7.5%、57.5%和100%。脱毒菌株的菌丝生长速度、生物量、漆酶活力等均优于出发菌株、菌丝尖端和原基组织分离菌株。【结论】这5种方法中原生质体单核化、有性生殖和核迁移脱毒法脱毒效果较佳,均能有效脱除FvBV,脱毒率高,脱毒后菌株菌丝生长速度、生物量、漆酶活力等均明显提高。 相似文献
6.
香菇病毒HKB(Lentinula edodes mycovirus HKB,LeV)是一种具有潜隐性特点的真菌病毒,广泛存在于香菇菌株中。为了快速、准确地检测出LeV,根据LeV病毒基因组序列(AB.429556.2)的信息,设计合成一对引物,对25个香菇菌株进行RTPCR检测,在20个香菇菌株中分别扩增出LeV病毒基因组特有的条带,在5个香菇菌株中未能扩增出条带。通过对25个香菇菌株进行dsRNA提取检测,结果也表明不存在扩增片段的菌株提取不到dsRNA,存在扩增片段的菌株能够提取得到dsRNA。因此建立的RT-PCR方法可以快速检测到香菇dsRNA病毒LeV,能够对香菇的质量检测提供技术支持。 相似文献
7.
不同寄主来源的灰葡萄孢对番茄的致病力分化研究 总被引:4,自引:0,他引:4
从安徽合肥、蚌埠、长丰、和县等市、县的番茄、辣椒、草莓、葡萄等发病寄主上分离鉴定获得18个灰葡萄孢Botrytis cinerea菌株,采用菌丝块创伤接种法,分别测定了上述不同寄主来源的灰葡萄孢菌对番茄果实和叶片的致病力.结果表明,所有供试菌株接种番茄果实后均引起发病,但不同菌株所致病斑的平均直径有显著差异,显示灰葡萄孢菌株间对番茄果实的致病力存在明显分化.按照在番茄果实上所致病斑的平均直径大小可将供试菌株致病力划分为较强、中等和较弱3种类型.总体来说,来自番茄的菌株对番茄果实的致病力较强,来自草莓、葡萄和辣椒的菌株对番茄果实的致病力较弱,但来自相同寄主的菌株间致病力也存在差异,菌株致病力差异与菌株地域来源无明显相关.供试灰葡萄孢菌株接种番茄叶片后,除CF1外,均可引起番茄叶片发病,但不同菌株所致番茄叶片病斑的平均直径也有显著差异;供试菌株对番茄叶片的致病力差异与菌株的寄主和地域来源无显著相关. 相似文献
8.
日本菟丝子的生物防治研究初报危害性及寄生真菌的筛选 总被引:1,自引:0,他引:1
危害林木的菟丝子在广西主要是日本菟丝子(Cuscuta aponica Choisy),其危不仅表现在它寄生的普遍性和严重性。还表现在它寄生的持久性。其中以龙眼、柚子、桂花、台湾相思等被害严重。 在菟丝子寄生真菌的筛选中发现(1)对日本菟丝子有较强致病力的菌株是刺盘孢菌(Colletotrichum spp)。(2)这些菌株中的绝大多数对同种寄主上含不同色素的同种菟丝子有不同的致病力,仅有少数表现相近似的,但它们的致病力相对较弱。(3)对大多数菌株来说,同一菌株对来源于不同寄主上的同种色泽的同种菟丝子有不同的致病力。 相似文献
9.
从地理位置不同,V—C组不同的13株小麦全蚀病菌中分离到直径23—36纳米的病毒。聚丙烯酰胺凝脉电泳表明这些菌株中的病毒dsRNA的组分及分子量不同。泰安株病毒有分子量为3.45,2.95,1.60,1.52,1.30,1.25,1.15,1.00,<1.00×10~6的9个dsRNA,而浙江、湖北菌株仅有一个组分、分子量为3×10~6。多数病毒衣壳多肽的的分子量为66×10~3—73×10~3。泰安菌株与烟台菌株病毒抗血清除与张家口菌株、青海菌株无反应外与其它菌株病毒均有反应,但在免疫双扩散中抗血清的滴定度不同。 相似文献
10.
采用组织块法从马尾松(Pinus massoniana Lamb.)根、茎和叶片中分离获得内生真菌,初步筛选出产油脂菌株且对其油脂含量进行了分析;并采用形态学及分子生物学方法对产油脂菌株进行了分类鉴定。结果显示:从马尾松植株中共获得21株内生真菌菌株,其中分离自根、茎和叶片的菌株分别为4株、6株和11株。有14株菌株的菌丝中有油滴;其中,分离自叶片的菌株ZP-1、分离自根的菌株ZP-2和分离自茎的菌株ZP-3的菌丝内油滴较多且油脂含量较高,平均油脂含量分别达到29.12%、25.03%和30.56%,差异极显著(P<0.01)。不同菌株的菌落颜色、菌丝和分生孢子形态特征明显不同,菌株ZP-1、ZP-2和ZP-3的形态分别与拟青霉属(Paecilomyces Bainier)、生赤壳菌属(Bionectria Speg.)和镰刀菌属(Fusarium Link)菌种的形态相似。与GenBank中相关真菌ITS序列的比对以及NJ系统树分析结果显示:菌株ZP-1与拟青霉属、菌株ZP-2与生赤壳菌属、菌株ZP-3与镰刀菌属间的ITS片段序列相似性均达到99%,在各自的NJ系统树上它们也分别聚在一起。初步确定菌株ZP-1、ZP-2和ZP-3分别属于拟青霉属、生赤壳菌属和镰刀菌属。 相似文献
11.
A number of field isolates of avian reovirus were characterized by analysis of the migration pattern of their genomic double-stranded RNA (dsRNA) segments upon polyacrylamide gel electrophoresis. Comparison of the various isolates has demonstrated (i) no relationship between serotype and migration of any individual dsRNA segment, (ii) marked polymorphism of migration patterns of all dsRNA segments among isolates of the same serotype as well as among different serotypes, (iii) no correlation between genotype and disease state, (iv) less marked variability in migration pattern from isolates within a restricted geographic locale compared to isolates from distant locales, (v) the presence of a single genotype in local outbreaks of disease, and (vi) the relative invariant migration of several dsRNA segments among the avian reoviruses, one of which (S1) may serve to distinguish the avian from the mammalian reoviruses. 相似文献
12.
研究了栗疫病菌[Cryphonectria parasitica(Murr.)Barr]的营养体亲和性基因及dsRNA病毒对菌株间病毒特征传播的影响。试验选用已知4个VC基因座位的15个Vc基因型菌株和3种dsRNA病毒,通过含病毒菌株与野生型菌株的配对培养,将病毒逐个转入不同Vc基因型菌株。将不同Vc基因型的含病毒菌株与具特定VC基因差异的野生型菌株配对培养,根据培养两周后野生型菌株培养性状的改变与否,统计菌株间的病毒传播率。结果表明,各个VC基因对菌株间病毒传播的影响不同;存在2个VC基因差异的菌株间病毒传播率低于相差1个VC基因的:病毒在相差1个VC基因的菌株间的传播多具单向性:不同类型的病毒在菌株间的传播率也有差异。 相似文献
13.
The genetic relationships among double-stranded RNAs (dsRNAs) from 76 isolates ofDiscula destructiva obtained from different geographic locations from New York to Alabama were studied by dot-blot hybridization. The dsRNA segments, identified by agarose gel electrophoresis, varied in size and number. Probes were constructed from total dsRNA from six isolates with different dsRNA profiles and of different geographic origins. Each probe hybridized with dsRNA from ca. 62% of the isolates under the high-stringency washing conditions used. No major differences in the percentage of the total isolates that hybridized with each probe were observed. These results suggest a recent common origin of these isolates ofD. destructiva. 相似文献
14.
Didymella bryoniae, isolate 98–18, recovered from watermelon seedlings with symptoms of gummy stem blight, showed abnormal growth, mycelial lysis, sectoring, barrage and limited production of fruiting bodies in culture. A dsRNA (approximately 6.5 kbp) was associated with isolate 98–18 and other isolates showing abnormal mycelial growth. Transfer of dsRNA from 98–18 to virulent isolates Tk659 and TK671 via hyphal anastamosis was achieved only by consecutive exposure to 98–18, but not to virulent isolates RJ1 and RJ2. Transfer of dsRNA via infiltration through growth media to virulent isolates RJ1, RJ2, TK659 and TK671 was unsuccessful. The disease severity index of isolate 98–18 was reduced 53% on watermelon, 32% on cataloupe and 26% on yellow squash compared with isolate RJ2, suggesting that the presence of the dsRNA is associated with reduced virulence of D. bryoniae isolate 98–18. Zucchini and yellow squash were resistant to both isolates when tested. 相似文献
15.
Multiple double-stranded RNA segments are associated with virus particles infecting Trichomonas vaginalis. 总被引:10,自引:3,他引:7
下载免费PDF全文
![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Previous studies demonstrated that some isolates of the sexually transmitted protozoan Trichomonas vaginalis are infected with a nonsegmented, double-stranded RNA (dsRNA) virus. A reexamination of the total dsRNA extracted from several virus-harboring isolates indicated the presence of at least three dsRNAs with sizes ranging from 4.8 to 4.3 kbp. The double-stranded nature of each of the three segments was determined by hybridization experiments using riboprobes of opposite polarities obtained from cDNA generated to each of the segments. All three segments were present in agar clones originating from single organisms of T. vaginalis isolates, suggesting that the three segments were not the result of a mixed population of trichomonads harboring different sizes of dsRNA. The three segments were associated with CsCl-purified virus particles, as evidenced by electron microscopy, and RNAse treatment of the preparation containing virus particles did not destroy the dsRNAs. Finally, the individual dsRNA segments were purified for use as probes to determine whether the three dsRNAs shared any sequence homology. Each end-labeled dsRNA segment did not cross-hybridize to any of the other two segments, a finding consistent with the hybridization of labeled cDNAs to only the segments from which they were derived. These results show that the coding capacity of the dsRNA virus may be at least three times greater than that estimated earlier and illustrates further the complexity of this virus-parasite interrelationship. 相似文献
16.
通过有机试剂抽提,CF-11纤维素柱层析,从感染水稻齿叶矮缩病毒菲律宾分离株(RiceRaggedStuntVirus,Philippineisolate,简称RRSV-P)的水稻植株中获取该病毒的全基因组,即获得从Segment1到Segment10(S1-S10)的10条双链RNA(dsRNA),然后设计合适的引物,用RT-PCR方法得到S9的cDNA并将其克隆到pUC119质粒上扩增,以双链测序法测定该cDNA的全序列。同时又将此cDNA克隆到大肠杆菌表达质粒pGEX-3X上,在大肠杆菌菌株DE3中用IPTG诱导表达,经超声波破菌、离心、Glutathione-sepharose4B亲和层析,得到纯化的分子量为64kD的融合蛋白。 相似文献
17.
18.
C. Rodríguez‐García V. Medina A. Alonso M.A. Ayllón 《The Annals of applied biology》2014,164(1):46-61
Botrytis cinerea (teleomorph Botryotinia fuckeliana) is a necrotrophic plant pathogenic fungus that causes grey mould and enormous economic losses worldwide in different crops. Control of B. cinerea is difficult due to the appearance of fungicide‐resistant isolates, and the diversity in virulence due to genetic variability and, perhaps, the infection with mycoviruses or fungal viruses. The discovery of mycoviruses and their possible application as biocontrol agents, as well as their use as tools to study the plant–pathogen interaction, has encouraged their study in B. cinerea. Herein, we have analysed the occurrence of mycoviruses in Spanish B. cinerea isolates to approach a better understanding of the interactions among viruses, fungi and plants in this pathosystem. Fifty‐five percent of the B. cinerea isolates analysed contained double‐stranded RNA (dsRNA) elements, and the number of dsRNA elements, their relative concentration and size were variable among isolates. Some of these dsRNAs were related to the presence of virus like rod or isometric particles, and to cellular degeneration and malformed mitochondria. We have also demonstrated that a 3 kb dsRNA present in 55% of the isolates having dsRNA elements was a mycovirus genome. Partial sequence of that mycovirus presented high identity in nucleotide and amino acid sequence with Botrytis cinerea mitovirus 1 (BcMV1). Analysis of the genetic distance within Spanish BcMV1 sequences showed the existence of different isolates of this mitovirus inside the Spanish B. cinerea population analysed. This is the first report of the variability of dsRNA elements and the partial genome sequence of a mitovirus associated with Spanish B. cinerea isolates and the genetic diversity within Spanish isolates of BcMV1. 相似文献
19.
综述了松毛虫CPV不同分离株基因组电泳图谱的研究状况。松毛虫CPV是松毛虫Dedrolimusspp .的重要病原微生物 ,在松毛虫灾害治理中起着重要作用。病毒基因组电泳图谱是CPV重要的分类依据和研究基础。到目前为止 ,全世界范围共分离报道了 1 0株不同的松毛虫CPV ,基因组电泳图谱研究表明CPV -1型是松毛虫CPV的主要类型。PAGE分析显示 ,松毛虫CPV不同分离株中至少存在有 3种不同CPV -1的型内变异 ,它们有时以纯一型或混合型的形式出现。特别需要指出的是中国马尾松毛虫CPV分离株 ,其存在有 2种不同形态的病毒多角体 ,通过蔗糖密度梯度离心可以分为上下 2条带 ,上带多角体为锥形 ,基因组dsRNA电泳图谱显示 1 3条带 ,不属于目前已确定的 1 4种电泳型中的任何一种 ;下带多角体为六边形 ,基因组为纯合的CPV -1型 ;另外在不同时期不同地方感染马尾松毛虫也分离得到了纯合型的马尾松毛虫CPV -型 相似文献