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1.
This study investigated the distribution and characteristics of the Barley yellow dwarf virus (BYDV) species BYDV‐PAS, which was recently separated from BYDV‐PAV, the most commonly studied BYDV species. Throughout 3 years of experimental monitoring of BYDV incidence, PAS was the most frequently occurring species infecting cereals and grasses in the Czech Republic. Furthermore, Rhopalosiphum maidis and Metopolophium dirhodum were recorded as BYDV‐PAS vectors, even though M. dirhodum does not usually transmit BYDV‐PAV. In field experiments with barley and wheat, where virus accumulation, symptoms and effect on the yield were tested, BYDV‐PAV was more severe than PAS. Infection with the BYDV‐PAV isolate resulted in greater expression of symptoms and also in a greater reduction in plant height and grain weight per spike than BYDV‐PAS. In a sensitive cultivar of barley (Graciosa), the amount of viral RNA of BYDV‐PAV was also significantly higher than that of BYDV‐PAS. In a tolerant line (Wbon‐123), however, no such differences were found. In conclusion, although BYDV‐PAS seems to be dominant in the Czech Republic, BYDV‐PAV has the potential to cause more significant crop losses in barley and wheat.  相似文献   

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3.
The prevalence of viruses in pepper crops grown in open fields in the different agro‐ecological zones (AEZs) of Côte d'Ivoire was surveyed. Pepper veinal mottle virus (PVMV; genus Potyvirus) and Cucumber mosaic virus (CMV; genus Cucumovirus) were the most frequent viruses among those surveyed, while tobamoviruses (genus Tobamovirus) were detected at low frequency. PVMV showed a high heterogeneity across AEZs, which may be related to climatic, ecological or agronomical conditions, whereas CMV was more homogeneously distributed. The molecular diversity of CMV and PVMV were analysed from partial genome sequences. Despite the low number of CMV isolates characterized, two molecular groups were revealed, one corresponding to subgroup IA and the other to reassortants between subgroups IA and IB. RNAs 1 and 3 of the reassortants clustered with the IB subgroup of CMV isolates, whereas their RNA 2 clustered with the IA subgroup. Importantly, RNA 1 of CMV isolates of the IB subgroup has been shown to be responsible for adaptation to pepper resistance. The diversity of PVMV in the VPg‐ and coat protein‐coding regions revealed multiple clades. The central part of the VPg showed a high level of amino acid diversity and evidence of positive selection, which may be a signature of adaptation to plant recessive resistance. As a consequence, for efficient deployment of resistant pepper cultivars, it would be desirable to examine the occurrence of virulent isolates in the CMV or PVMV populations in Côte d'Ivoire and to follow their evolution as the resistance becomes more widely deployed.  相似文献   

4.
Cucumber mosaic virus is one of the most prevalent viruses in Tunisian pepper crops, where it has been detected in 68% of plants developing mosaic symptoms, making it essential to characterize the molecular and biological properties of local CMV populations. Two hundred and seventy‐eight isolates collected in the late 1990s, 2006 and 2008–2010 were characterized genetically. Isolates belonging to the three phylogenetic subgroups of CMV (IA, IB and II) were detected, but surprisingly, 90% of the isolates were reassortants between subgroups IA and IB, with two predominant haplotypes, IB‐IA‐IA and IB‐IA‐IB (nomenclature according to the subgrouping of the three genomic RNAs). The IB‐IA‐IA haplotype was present in all regions surveyed, while IB‐IA‐IB was observed only in northern Tunisia. This situation was unexpected, because CMV reassortants were previously thought to be counterselected in nature, and this raises the questions of the origin of IB strains in Tunisia and of the widespread distribution of these two reassortant types. Phylogenetic studies revealed low diversity within haplotypes, whatever the locality or the year of sampling. However, analysis of haplotype frequencies revealed a high genetic differentiation between CMV populations, which was better explained by the localities of sampling than by years. Geographic distances affected the differentiation of CMV populations, mainly between north and central Tunisia. When tested against a polygenic resistance to CMV movement in pepper, 55 of 57 isolates tested were able to break the resistance, indicating that this resistance would not be useful for controlling CMV in Tunisian pepper fields.  相似文献   

5.
为了评价河南省主要推广品种对小麦黄花叶病毒(Wheat yellow mosaic virus, WYMV)的抗性,于2006—2010年在河南省西平县病圃进行了田间抗性鉴定试验和室内间接ELISA检测,并分析了病害严重程度对产量的影响。结果表明,在供试的62个品种中,仅有新麦208表现为免疫;豫麦70-36、泛麦5号、阜麦936、山东95519、豫麦70、高优503、豫麦9676、郑麦366和陕麦229等9个品种表现为抗病,占供试品种的14.5%;濮优938、兰考矮早8、新原958、花培2号、温优1号、豫麦18、郑麦9023、豫麦47、豫农201、偃展4110、豫麦36、百农878和豫麦49-198等13个品种表现为中抗,占供试品种的21.0%;另外39个品种表现为感病,占供试品种的62.9%。对48个品种进行了产量与病害严重度分析,发现随着病害的严重度增加,小麦的穗数、千粒重以及产量都有明显下降,严重度为1级时,平均减产9.6%;严重度达到2级和3级时,平均减产分别为30.3%和33.5%。  相似文献   

6.
Tomato yellow leaf curl disease is one of the most devastating viral diseases affecting tomato crops worldwide. This disease is caused by several begomoviruses (genus Begomovirus, family Geminiviridae), such as Tomato yellow leaf curl virus (TYLCV), that are transmitted in nature by the whitefly vector Bemisia tabaci. An efficient control of this vector‐transmitted disease requires a thorough knowledge of the plant–virus–vector triple interaction. The possibility of using Arabidopsis thaliana as an experimental host would provide the opportunity to use a wide variety of genetic resources and tools to understand interactions that are not feasible in agronomically important hosts. In this study, it is demonstrated that isolates of two strains (Israel, IL and Mild, Mld) of TYLCV can replicate and systemically infect A. thaliana ecotype Columbia plants either by Agrobacterium tumefaciens‐mediated inoculation or through the natural vector Bemisia tabaci. The virus can also be acquired from A. thaliana‐infected plants by B. tabaci and transmitted to either A. thaliana or tomato plants. Therefore, A. thaliana is a suitable host for TYLCV–insect vector–plant host interaction studies. Interestingly, an isolate of the Spain (ES) strain of a related begomovirus, Tomato yellow leaf curl Sardinia virus (TYLCSV‐ES), is unable to infect this ecotype of A. thaliana efficiently. Using infectious chimeric viral clones between TYLCV‐Mld and TYLCSV‐ES, candidate viral factors involved in an efficient infection of A. thaliana were identified.  相似文献   

7.
烟草品种对烟草花叶病毒病和黄瓜花叶病毒病的抗性鉴定   总被引:1,自引:0,他引:1  
由烟草普通花叶病毒(TMV)和烟草黄瓜花叶病毒(CMV)引致的烟草病毒病是世界烟草主产区普遍发生且危害严重的侵染性病害,每年给烟叶生产造成了重大的经济损失。本文采用温室苗期接种鉴定的方法,对16份烟草种质进行了TMV和CMV的抗病性鉴定。结果表明:不同的烟草品种对TMV和CMV的抗病性存在较大差异。在供试种质中,对TMV表现免疫的有‘牛耳烟’、‘8301’、‘台烟7号’、‘三生-NN’共4份材料;表现抗病的有‘吉烟5号’、‘双抗70’、‘大护脖香’、‘秦烟95’共4份材料;表现中抗的有‘铁把子’、‘中烟15’、‘秦烟98’、‘中烟98’共4份材料;表现中感的有‘NC89’、‘翠碧1号’、‘云烟97’共3份材料;表现感病的只有‘秦烟97’。对CMV表现中抗的材料有1份,是‘铁把子’;表现中感的有‘秦烟95’、‘三生-NN’、‘8301’、‘牛耳烟’、‘翠碧1号’共5份材料;表现感病的有‘秦烟98’、‘云烟97’、‘中烟98’、‘NC89’、‘大护脖香’、‘双抗70’、‘秦烟97’、‘中烟15’、‘台烟7号’、‘吉烟5号’共10份材料。研究发现,‘铁把子’是兼抗这两种病毒病的材料。本研究明确了我国16个烟草品种资源的抗病性水平,为抗耐病品种的利用与品种合理布局提供科学依据,同时为烟草抗病毒病育种的亲本选择提供抗源信息。  相似文献   

8.
小麦黄花叶病是由禾谷多黏菌传播的小麦黄花叶病毒引起的病害,近年在黄淮麦区呈蔓延加重趋势。为了给病害的防治和抗病育种工作提供依据,本研究利用分级评价方法对黄淮地区推广的小麦品种进行了田间抗病性鉴定。两年鉴定结果表明,在145个供试小麦品种中,‘濮优938’、‘新麦208’、‘豫麦416’、‘新原958’、‘豫麦70-36’、‘泛麦5号’等70个品种表现为免疫,占总数的48.28%;‘豫麦47’和‘邯6172’表现为抗病,占总数的1.38%;‘洪育2号’、‘花培2号’、‘偃展4110’、‘豫麦41’、‘郑麦9023’等48个品种表现为中抗,占总数的33.10%;‘兰天06129’、‘兰天0591’、‘徐麦9158’、‘徐麦0054’、‘徐麦1108’等25个品种表现为感病,占总数的17.24%。研究结果为指导小麦黄花叶病区合理选择小麦品种提供了科学依据。  相似文献   

9.
Yellow vein mosaic disease (YVMD) caused by whitefly‐transmitted begomoviruses is an economically significant viral disease of okra. In this study, a survey of begomoviruses associated with YVMD was carried out in eight states and two union territories of India. A total of 92 full‐length DNA‐A components were sequenced and characterized. Sequence comparisons and population structure analysis revealed the existence of four begomovirus species. Two novel species were detected with several recombinationally derived genome fragments that probably originated from begomoviruses known to infect malvaceous and non‐malvaceous hosts. Among the four species, Bhendi yellow vein Maharastra virus (BYVMaV) and Bhendi yellow vein Madurai virus (BYVMV) were found to be predominant in okra, with BYVMV having a pan‐India distribution. There was evidence for a high degree of genetic variability and subpopulation structure within these four species. Neutrality tests suggested the occurrence of purifying selection acting upon these populations. The results of the current study have uncovered the diversity and genetic structure of okra‐infecting begomoviruses in India and generated potentially useful information for developing management strategies for YVMD.  相似文献   

10.
烟草品种对烟草花叶病毒和黄瓜花叶病毒的抗性鉴定   总被引:1,自引:0,他引:1  
 2010-2011年采用大田人工接种鉴定的方法,对生产中大面积推广使用的24份烟草品种进行了烟草花叶病毒(TMV)和黄瓜花叶病毒(CMV)的抗性鉴定。结果表明,供试品种对TMV和CMV的抗病性存在较大差异,对TMV表现抗病的有Coker86、吉烟5号、Coker176、CV87、辽烟8号、CV91、中烟90等7份材料;表现中抗的有秦烟98、双抗70、C151等3份材料;表现中感的有秦烟96、G80、金星6007、龙江981、K326、秦烟201、NC89等7份材料;表现感病的有G28、云烟97、净叶黄、红花大金元、RG11、云烟85、云烟87等7份材料。对CMV表现抗病的有Coker86、龙江981、C151、秦烟201、云烟87等5份材料;表现中抗的材料是金星6007;表现中感的有CV91、RG11、Coker176、中烟90、K326、红花大金元、净叶黄、G80、G28等9份材料;表现感病的有秦烟98、云烟85、秦烟96、NC89、双抗70、云烟97、CV87、辽烟8号、吉烟5号等9份材料。其中兼抗TMV和CMV两种病毒病的材料有2份,分别是Coker86和C151。同时研究还发现,抗病性不同的烟草品种在受到病毒危害以后,对烟叶的产量和品质的影响也不同。明确了中国24个烟草品种的抗病性水平,为抗病品种的利用与品种合理布局提供科学依据,同时为烟草抗病毒病育种的亲本选择提供抗源信息。  相似文献   

11.
Iris yellow spot virus (IYSV, genus Tospovirus) is a viral disease of bulb and seed onion crops and is transmitted by Thrips tabaci. Foliage damage of up to 75% has been reported in Kenya and Uganda. In this study, the rate of IYSV replication in the larva, pupa and adult stages of T. tabaci and other non‐vector thrips species and colour forms such as Frankliniella occidentalis, F. schultzei (dark) and F. schultzei (pale) was evaluated by monitoring relative levels of nucleocapsid (N) and non‐structural (NSs) proteins using N‐ and NSs‐specific antibodies. The effect of IYSV replication on mortality of thrips was also determined. N protein levels increased in all three stages of IYSV‐fed T. tabaci, indicating replication of IYSV. In IYSV‐fed non‐vector thrips, the increase of N protein levels in the larval stage was lower than IYSV‐fed T. tabaci but higher than their healthy counterparts. The N protein levels did not increase at pupal and adult stages. NSs protein was not detected in first instar of either vector or non‐vector thrips species. After a 4 h post‐acquisition period, a significant increase in NSs proteins was only observed in IYSV‐fed T. tabaci, clearly differentiating vectors and non‐vectors of IYSV. IYSV replication did not influence the survival of the vector thrips species, T. tabaci populations or the non‐vector thrips species. This study indicates the effectiveness of monitoring non‐structural proteins such as NSs, compared to nucleocapsid proteins, for differentiating vectors and non‐vectors of IYSV.  相似文献   

12.
随着国际邮寄业务的迅速发展,外来有害生物随邮寄物入侵我国的风险与日剧增。2012年在韩国旅客携带的大豆种子中首次检出南方菜豆花叶病毒属新种大豆黄化普通花叶病毒(Soybean yellow common mosaic virus,SYCMV)后,近日在隔离种植的日本邮寄大豆种子中,通过多种方法再次检出该病毒。本文将详细分析DAS-ELISA,RT-PCR及序列测定分析的过程,以期为种子病毒的检测提供新的思路。  相似文献   

13.
Recombination has played an important role in evolution and genetic diversity of Sugarcane yellow leaf virus (SCYLV) isolates sequenced to date. This study found that three newly sequenced SCYLV sorghum isolates from the USA underwent intraspecies recombination. No statistical significance on probable progeny–parent relationships involving SCYLV sorghum isolates were found in possible interspecies recombination with 18 members of the Luteoviridae family. Sorghum isolates deposited in the GenBank database under accession numbers KT960995, KT960996 and KT960997 were phylogenetically closely related to SCYLV genotypes IND, CUB and CHN1, all members of phylogroup II. Networked relationships among the sorghum isolates showed that numerous incompatibilities occurred in the sequences. These conflicting signals were probably due to recombination, especially in KT960997, which was heavily impacted by recombination. The KT960997 accession was positioned on a distinct branch compared to other members of phylogroup II, suggesting that it has probably emerged as a new genotype. Future studies on molecular evolution may reveal further insights into the adaptation capacity of these SCYLV lineages to new environments.  相似文献   

14.
Zea mays has been historically imported to Japan via two independent geographical routes: into southern Japan by trading with Europe in the 16th century and into northern Japan by import from North America in the 19th century. Breeding to genetically improve on quality traits and high yields has led to the current domestic landraces in each region. In a survey of 82 domestic landraces, nine out of 38 landraces originating from southern Japan showed complete immunity to cucumber mosaic virus yellow strain (CMV(Y)) without the formation of necrotic local lesions (NLLs). In contrast, three out of 44 landraces originating from northern Japan developed NLLs, but revealed no systemic spread of the virus. Due to the absence of good documentation on NLL formation in Z. mays, the response of domestic landraces Aso‐1 and Aso‐3, originating from Ibaraki in northern Japan, to a challenge with CMV(Y) and CMV(Ma‐1) was further analysed. Aso‐3 only formed NLL in response to CMV(Y) but not to CMV(Ma‐1). Moreover, in CMV(Y)‐inoculated Aso‐3, virus spread was restricted to the primary infection site and the expression of defence‐related genes was up‐regulated, whereas Aso‐1 became systemically infected with either CMV(Y) or CMV(Ma‐1). The response of Aso‐3 to CMV(Y) was inherited as a single dominant trait. Together, these results pointed towards the induction of hypersensitive response (HR)‐mediated resistance to CMV(Y) in Aso‐3. Although HR‐mediated resistance to viruses has been studied mainly in dicots, the pathosystem CMV–Z. mays may provide a model to investigate HR‐mediated resistance to viruses in monocot plants.  相似文献   

15.
为明确青海省不同小麦种质资源对大麦黄矮病毒(Barley yellow dwarf virus,BYDV)的抗性差异,于2014—2015年采用堆测法人工接种鉴定了178份种质资源的抗病性。结果显示,不同小麦种质资源对黄矮病的抗性存在较大差异,甘A100、川766、陕1059、兰麦-2的病情指数依次为14.83、23.60、23.99和24.66,表现出较好的抗病性;病情指数在50.00以上的高感品种有69份,包括尕老汉、白板麦、兴热密穗等,其中白板麦病情指数高达72.35,高于感病对照阿勃;其余种质资源病情指数在25.00~50.00之间,表现为感病;甘A101、甘A99、藏515、藏519、木汉麦、群科大白麦、拉胎板麦、小红麦-2和朗县折达25初期表现感病,后期恢复健康,有一定的耐病性;抗病性不同的种质资源感染BYDV后,对小麦产量的影响差异很大,抗病对照中4产量损失8.96%,耐病品种产量损失在13.64%~19.74%之间,高病品种尕老汉产量损失达41.91%,表明小麦种质资源中抗BYDV的品种极少。  相似文献   

16.
Cassava common mosaic disease (CCMD) has been reported in all regions where cassava is grown in the Americas and the causal agent, Cassava common mosaic virus (CsCMV), has been identified as a mechanically transmitted potexvirus (Alphaflexiviridae). In Argentina, cassava is grown mainly in the northeast (NEA) region that shares borders with Brazil and Paraguay. Increasing incidences of CCMD were observed during the years 2014 to 2016 associated with severe leaf mosaic symptoms and yield reductions where the occurrence of CsCMV was confirmed by RT‐PCR and sequencing. In this work, the virus has been successfully purified and a double‐antibody sandwich (DAS‐) ELISA test has been developed from an Argentinean isolate of CsCMV to extend the diagnostics of the disease. A collection of 726 samples was screened and CsCMV was detected with 100% prevalence in the NEA region. Additional co‐infecting viruses were detected in some plants (64.4%); in these, CCMD symptoms correlated with CsCMV only, although more severe symptoms could be observed in mixed infected plants. Sequence analysis of the conserved RdRp domain showed a wider diversity of CsCMV isolates. Interestingly, a separate phylogenetic cluster was formed by isolates from the NEA region that only shared 77.1% to 80.3% nucleotide identity with the other clusters. These results indicate the presence of mixed strains occurring in the NEA region and suggest the presence of geographically distinct strains of CsCMV in South America.  相似文献   

17.
The development of plant diseases is associated with biophysical and biochemical changes in host plants. Various sensor methods have been used and assessed as alternative diagnostic tools under greenhouse conditions. Changes in photosynthetic activity, spectral reflectance and transpiration rate of diseased leaves, inoculated with Cucumber mosaic virus (CMV), Cucumber green mottle mosaic virus (CGMMV), and the powdery mildew fungus Sphaerotheca fuliginea were assessed by the use of non‐invasive sensors during disease development. Spatiotemporal changes in leaf temperature related to transpiration were visualized by digital infrared thermography. The maximum temperature difference within a leaf was an appropriate parameter to differentiate between healthy and diseased plants. The photosynthetic activity of healthy and diseased cucumber plants varied as measured by chlorophyll fluorescence and compared to the actual chlorophyll content. Hyperspectral imaging data were analysed using spectral vegetation indices. The results from this study confirm that each pathogen has a characteristic influence on the physiology and vitality of cucumber plants, which can be measured by a combination of non‐invasive sensors. Whereas thermography and chlorophyll fluorescence are unspecific indicators for plant diseases, hyperspectral imaging offers the potential for an identification of plant diseases. In a sensor data fusion approach, an early detection of each pathogen was possible by discriminant analysis. Although it still needs to be validated under real conditions, the combination of information from different sensors seems to be a promising tool.  相似文献   

18.
 小麦黄花叶病毒(Wheat yellow mosaic virus, WYMV)是马铃薯Y病毒科大麦黄花叶病毒属成员,主要危害冬小麦。实验室前期以WYMV外壳蛋白(coat protein,CP)为诱饵,通过酵母双杂交筛选小麦cDNA文库,发现FtsH2蛋白部分片段与WYMV CP互作。FtsH2蛋白是AAA蛋白酶家族成员,参与植物叶绿体光损伤修复和类囊体发育进程。本研究利用酵母双杂交和双分子荧光互补技术进一步对FtsH2蛋白全长与WYMV CP进行互作验证,并鉴定互作结构域;利用荧光蛋白标记技术研究FtsH2蛋白与CP的亚细胞定位。实验结果表明FtsH2蛋白全长与CP互作;两者互作的关键结构域包含FtsH2蛋白低复杂区、跨膜区及AAA结构域和WYMV CP的中段区域(61-293 aa)。FtsH2蛋白单独表达时定位在细胞质、细胞核和叶绿体;CP单独表达时定位在细胞质;两者共同表达时亚细胞定位均没有发生明显变化,且主要共定位于细胞质中。WYMV CP与小麦FtsH2蛋白的互作可能会干扰植物绿叶体的发育和功能。本研究对了解WYMV的症状形成机制具有一定意义。  相似文献   

19.
 为了获取影响大麦黄条点花叶病毒(BYSMV)在灰飞虱体内增殖、积累和传播的相关介体因子,本研究利用分离泛素酵母双杂交膜系统,以BYSMV核衣壳蛋白(N)为诱饵对灰飞虱cDNA文库进行了筛选。 将BYSMV N基因构建到诱饵载体pDHB1上进行表达检测和功能验证,结果表明重组载体pDHB1-N能在酵母内正常表达并行使功能。利用诱饵载体筛选pPR3-N空文库对文库筛选条件进行优化,确定3-氨基-1,2,4-三唑(3-AT)浓度为12 mmol·L-1的QDO平板为筛选文库培养基条件,去除可能存在的轻微筛库背景。在此筛选条件下以诱饵载体从灰飞虱cDNA文库中筛选得到57个阳性克隆,序列比对结果表明这些阳性克隆编码17种候选蛋白,包括表皮蛋白、泛素B、核糖体膜相关蛋白、细胞色素b5以及海藻糖转运蛋白等。 经酵母双杂交共转验证和β-半乳糖苷酶检测进一步确认了这17个候选蛋白与BYSMV N发生互作。本研究成功从灰飞虱分离泛素酵母双杂交膜系统cDNA文库筛选到与BYSMV N互作的蛋白质,为进一步探索弹状病毒与介体昆虫的分子互作机制奠定了基础。  相似文献   

20.
 小麦黄花叶病毒(Wheat yellow mosaic virus, WYMV)是马铃薯Y病毒科大麦黄花叶病毒属成员,主要危害冬小麦。实验室前期以WYMV外壳蛋白(coat protein,CP)为诱饵,通过酵母双杂交筛选小麦cDNA文库,发现FtsH2蛋白部分片段与WYMV CP互作。FtsH2蛋白是AAA蛋白酶家族成员,参与植物叶绿体光损伤修复和类囊体发育进程。本研究利用酵母双杂交和双分子荧光互补技术进一步对FtsH2蛋白全长与WYMV CP进行互作验证,并鉴定互作结构域;利用荧光蛋白标记技术研究FtsH2蛋白与CP的亚细胞定位。实验结果表明FtsH2蛋白全长与CP互作;两者互作的关键结构域包含FtsH2蛋白低复杂区、跨膜区及AAA结构域和WYMV CP的中段区域(61-293 aa)。FtsH2蛋白单独表达时定位在细胞质、细胞核和叶绿体;CP单独表达时定位在细胞质;两者共同表达时亚细胞定位均没有发生明显变化,且主要共定位于细胞质中。WYMV CP与小麦FtsH2蛋白的互作可能会干扰植物绿叶体的发育和功能。本研究对了解WYMV的症状形成机制具有一定意义。  相似文献   

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