首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 36 毫秒
1.
ABSTRACT Experiments over two growing seasons clearly showed that Turnip mosaic virus (TuMV) infection was associated with internal necrosis (sunken necrotic spots 5 to 10 mm in diameter) and Beet western yellows virus (BWYV) infection was associated with collapse of leaf tissue at the margins (tipburn) in heads of stored white cabbage (Brassica oleracea var. capitata). Virtually no tipburn was seen in cv. Polinius, whereas cv. Impala was affected severely. Internal necrotic spots were seen in both cultivars. BWYV appeared to interact with TuMV. Plants infected with both viruses showed a lower incidence of external symptoms and had less internal necrosis than plants infected with TuMV alone. Cauliflower mosaic virus (CaMV) did not induce significant amounts of internal necrosis or tipburn, but did, in most cases, exacerbate symptoms caused by TuMV and BWYV. BWYV-induced tipburn worsened significantly during storage. Post-transplanting inoculation with TuMV induced more internal necrosis than pre-transplant inoculation. There was a significant association between detection of TuMV just prior to harvest and subsequent development of internal necrotic spots. Individually, all three viruses significantly reduced the yield of cv. Polinius, whereas only BWYV and CaMV treatments reduced the yield of cv. Impala.  相似文献   

2.
 从浙江宁波雪里蕻上获得97株呈花叶症状的病毒样品,利用三抗体夹心酶联免疫吸附测定(TAS-ELISA)在97株雪里蕻花叶样品中均检测到芜菁花叶病毒(Turnip mosaic virus,TuMV),所有的样品都没有检测到黄瓜花叶病毒(Cucumber mosaic virus,CMV)和烟草花叶病毒(Tobacco mosaic virus,TMV);利用免疫捕捉反转录PCR (IC-RT-PCR)对部分TuMV样品中的CP和HC-Pro基因进行了扩增,所有样品都得到约0.8kb和1.4kb的2条特异条带,因此宁波雪里蕻花叶病的主要病原是TuMV。对53个雪里蕻栽培品种在温室和大田进行了人工接种,共鉴定出抗病品种7个,耐病品种22个,感病品种24个,未发现高抗品种。总的来说,细叶型品种比花叶型和板叶型品种抗病。利用TAS-ELISA方法对接种的53个雪里蕻品种中的TuMV浓度进行测定,在接种后10、15、20和30d,TuMV检出率分别为45.28%、90.57%、100%和100%,大多数雪里蕻OD405值随接种后天数的增加而呈上升趋势,说明TuMV可以在雪里蕻抗性品种内繁殖,抗性品种的抗性主要表现为耐病。  相似文献   

3.
The incidence and severity of three diseases of oilseed rape, caused by beet western yellows luteovirus (BWYV), cauliflower mosaic caulimovirus (CaMV) and turnip mosaic potyvirus (TuMV), were assessed in England and Wales in the springs of 1992 and 1993. In 1992, 62% of oilseed rape crops examined were found to contain BWYV, with an average of 28% plants infected; 14% of crops contained CaMV, with an average of 5% plants infected; and TuMV with 3% crops and < 1% plants infected. In 1993, BWYV was found in 42% of crops and 12% of plants infected; CaMV in 25% of crops and 7% of plants infected; and TuMV in 14% of crops and 5% plants infected. The yields of plants showing severe virus symptoms were reduced by an estimated 70 to 79%. The high incidence of CaMV and TuMV in oilseed rape crops could have important consequences for rapeseed production in the UK and also serve as a source of virus for vegetable brassicae.  相似文献   

4.
Programmed cell death (PCD) pathways caused by Turnip mosaic virus (TuMV) infection before symptom appearance were studied by light microscopy and electrolyte leakage following sap inoculation of Brassica carinata (Ethiopian mustard) TZ‐SMN‐44‐6 plants. Leaf responses to inoculation with avirulent (TuMV‐avir) and virulent (TuMV‐vir) isolates, and mock‐inoculation, were compared at 2, 20 and 52 h after inoculation (hai). The phenotypes induced were localized resistance (TuMV‐avir) and systemic susceptibility (TuMV‐vir). No visible TuMV symptoms were recorded in any inoculated plants during the 2–52 hai sampling period, but appeared as chlorotic spots in inoculated leaves at 5 days after inoculation. With TuMV‐vir alone, they were followed by systemic infection (mosaic). Dead cell number, deformation, percentage area and percentage integrated intensity, and conductivity of electrolyte leakage data, were analysed to examine their possible roles in stimulating cell death pathways. At 2 hai, dead cell number and percentage area were significantly greater for TuMV‐avir than TuMV‐vir infection or mock‐inoculation. Overall, isolate TuMV‐vir caused significantly greater cell deformation than TuMV‐avir, whereas wounding by mock‐inoculation had negligible effects. By 52 hai, isolate TuMV‐avir caused significantly greater electrolyte leakage than isolate TuMV‐vir or mock‐inoculation. This suggests both isolates triggered morphological changes consistent with apoptotic‐like PCD and necrosis‐like PCD that depended upon isolate virulence and stage of infection, respectively. These findings highlight how quantification of dead cell deformation and electrolyte leakage offer a new understanding of compatible and incompatible plant responses to early virus infection in plants.  相似文献   

5.
Brassica rapa can be infected with Turnip mosaic virus (TuMV) as a result of manual inoculation or aphid transmission, but infected plants have not been found in the field. In this study, B. rapa plants grown from seed collected from two field sites in southern England were mechanically inoculated with one of two distinct isolates (pathotypes) of TuMV under glasshouse conditions. These had either been isolated from Brassica oleracea growing wild in Wales, (GBR 83, pathotype 3) or Dorset (GBR 98, pathotype 1). Use of ELISA as an index of infection in manually inoculated B. rapa showed that although seed provenance had a small effect on the proportion of plants infected, the biggest factor was the virus isolate. Both virus isolates infected both lines of B. rapa , but invaded at different rates, although both resulted in easily discernible symptoms. The severity of symptoms was not related to amounts of virus in the infected plants. A significantly greater proportion of plants were infected with GBR 83 at 45 days post-inoculation (d.p.i.) than GBR 98. but GBR 98 caused significantly more severe and obvious symptoms as well as greater mortality at 119 d.p.i., in plants from both sites than GBR 83.  相似文献   

6.
ABSTRACT Soilborne wheat mosaic virus (SBWMV) is an agronomically important pathogen of wheat that is transmitted by the soilborne plasmodiophorid vector Polymyxa graminis. In the laboratory, attempts to generate SBWMV-infected plants are often hampered by poor infectivity of the virus. To analyze the mechanism for virus resistance in wheat cultivars, we developed novel inoculation techniques. A new technique for foliar inoculation of SBWMV was developed that eliminated wound-induced necrosis normally associated with rub inoculating virus to wheat leaves. This new technique is important because we can now uniformly inoculate plants in the laboratory for studies of host resistance mechanisms in the inoculated leaf. Additionally, wheat plants were grown hydroponically in seed germination pouches and their roots were inoculated with SBWMV either by placing P. graminis-infested root material in the pouch or by mechanically inoculating the roots with purified virus. The susceptibility of one SBWMV susceptible and three field resistant wheat cultivars were analyzed following inoculation of plants using these novel inoculation techniques or the conventional inoculation technique of growing plants in P. graminis-infested soil. The results presented in this study suggest that virus resistance in wheat likely functions in the roots to block virus infection.  相似文献   

7.
A strain of Cucumber mosaic virus (CMV-D8) systemically infects Japanese radish (Raphanus sativus), but the Y strain of CMV (CMV-Y) only infects the inoculated leaves. Both of these strains cause severe systemic mosaic on the plants after dual infection with Turnip mosaic virus (TuMV). Synergistic interactions on long-distance transport of CMV-Y and CMV-D8 with TuMV were analyzed using an immunobinding assay. Direct tissue blots probed with either anti-CMV-Y or anti-TuMV antiserum clearly showed that CMV-Y efficiently spread and accumulated in the tissues of noninoculated upper leaves and roots when co-inoculated with TuMV, and that long-distance movement of CMV-D8 was enhanced by the presence of TuMV. Received 16 September 1999/ Accepted in revised form 5 February 2000  相似文献   

8.
Beet yellows virus (BYV), beet mild yellowing virus (BMYV), beet chlorosis virus (BChV), and beet mosaic virus (BtMV) cause virus yellows (VY) disease in sugar beet. The main virus vector is the aphid Myzus persicae. Due to efficient vector control by neonicotinoid seed treatment over the last decades, there is no current knowledge regarding virus species distribution. Therefore, Europe-wide virus monitoring was carried out from 2017 to 2019, where neonicotinoids were banned in 2019. The monitoring showed that closterovirus BYV is currently widely spread in northern Europe. The poleroviruses BMYV and BChV were most frequently detected in the northern and western regions. The potyvirus BtMV was only sporadically detected. To study virus infestation and influence on yield, viruses were transmitted to sugar beet plants using viruliferous M. persicae in quadruplicate field plots with 10% inoculation density simulating natural infection. A plant-to-plant virus spread was observed within 4 weeks. A nearly complete infection of all plants was observed in all treatments at harvest. In accordance with these findings, a significant yield reduction was caused by BMYV and BChV (−23% and −24%) and only a moderate reduction in yield was observed for BYV (−10%). This study showed that inoculation at low densities mimics natural infection, and quick spreading induced representative yield effects. Within the background of a post-neonicotinoid era, this provides the basis to screen sugar beet genotypes for the selection of virus tolerance/resistance and to test the effectiveness of insecticides for the control of M. persicae with a manageable workload.  相似文献   

9.
Serotypic variation in turnip mosaic virus   总被引:7,自引:0,他引:7  
Jenner  Keane  Jones  & Walsh 《Plant pathology》1999,48(1):101-108
A panel of 30 monoclonal antibodies (MAbs) was produced against four isolates of turnip mosaic virus (TuMV). The panel was tested in plate-trapped antigen ELISA tests against 41 TuMV isolates (with different host and geographical origins and of differing pathotypes). The antibodies were also tested against four other potyviruses (bean common mosaic virus, bean common mosaic necrosis virus, lettuce mosaic virus and zucchini yellow mosaic virus). The reactions were assessed quantitatively (using multivariate analysis) and qualitatively (using the standard deviation obtained against healthy leaf material). The MAbs recognized 16–17 TuMV epitopes that were not present in the other potyviruses and a further two potyvirus epitopes. The isolates were grouped into three serotypes. Only one isolate did not fit this grouping. The classification of seven isolates in coat protein amino acid sequence homology groups correlated with serotypes. There was no correlation between serotype and pathotype, or between reactions to individual MAbs and single lines. There was therefore no evidence that the epitopes recognized by the MAbs are elicitors for the resistance genes present in the Brassica napus lines. However, the sensitivity and specificity of the MAbs will be useful for both routine detection of TuMV and fundamental studies on plant–virus interactions.  相似文献   

10.
Alfalfa (Medicago sativa) cv. Beaver was screened for resistance to alfalfa mosaic virus (AIMV). A1MV infection in clonal plants was tested by double-antibody sandwich ELISA 4 and 8 weeks after inoculation with purified A1MV (1 mg/ml in 0025 M phosphate buffer, pH 7 0). Twelve clones showed a hypersensitive reaction 3–4 days after inoculation and the infection was restricted to the inoculated leaves. All the plants of hypersensitive clones consistently produced local lesions when inoculated with purified AIM V. In contrast, plants inoculated with AIMV in crude sap remained symptomless, although AIMV was detectable in inoculated leaves. The remaining 16 clones were susceptible to AIMV and showed systemic infection.  相似文献   

11.
In order to study the defense response to turnip mosaic virus (TuMV) infection in non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino), we cloned the LRR II subfamily genes which comprises six members. They were high homologous to the function-known LRR II genes of Arabidopsis. We investigated their expression through quantitative real-time PCR analysis. TuMV infection induced the expression of these genes locally and systematically, and regulated the endogenous accumulation of salicylic acid (SA). Exogenous SA spraying was able to induce resistance to the susceptibility of the TuMV-infected plants, which might function via inhibiting the viral duplication. Though TuMV-induced SA accumulation was not the determinant in regulating gene expression, it mediated the reaction oxygen species (ROS) burst as a channel of defense.  相似文献   

12.
13.
Local lesion formation on cowpea leaves was more than 50% inhibited by treatment with a 23 kDa RNase-like glycoprotein from Cucumis figarei, figaren, from 24 hr before to 1 hr after inoculation with Cucumber mosaic virus (CMV). CMV accumulation detected by ELISA in tobacco leaves treated with figaren 6 or 0 hr before inoculation with CMV was suppressed. When upper leaves of tobacco plants were treated with figaren and inoculated 10 min later with CMV, mosaic symptoms were delayed for 5–7 days on most of the tobacco plants, and some plants remained asymptomatic. From fluorescence in situ hybridization, infection sites were present in figaren-treated cowpea or melon leaves after inoculation with CMV, though the sites were reduced in number and size compared with those in water-treated control leaves. The amount of CMV RNAs and CMV antigen in melon protoplasts inoculated with CMV and subsequently incubated with figaren similarly increased with time as did that in the control. ELISA and local lesion assays indicated that CMV infection on the upper surfaces of the leaves of tobacco, melon, cowpea and C. amaranticolor whose lower surfaces had been treated with figaren 5–10 min before CMV inoculation was almost completely inhibited. Figaren did not inhibit CMV infection on the opposite untreated leaf halves of melon, cowpea and C. amaranticolor, whereas it almost completely inhibited CMV infection on the untreated halves of leaves of tobacco. CMV infection was not inhibited in the untreated upper or lower leaves of the four plants. These data suggest that figaren does not completely prevent CMV invasion but does inhibit the initial infection processes. It may also induce localized acquired resistance in host plants. Received 10 October 2000/ Accepted in revised form 6 February 2001  相似文献   

14.
Turnip mosaic virus (TuMV) causes crop losses worldwide. Eight Australian TuMV isolates originally obtained from five different species in two plant families were inoculated to 14 plant species belonging to four families to compare their host reactions. They differed considerably in virulence in Brassicaceae crop species and virus indicator hosts belonging to three other families. The isolates infected most Brassica species inoculated, but not Raphanus sativus, usually causing systemic mosaic symptoms, so they resembled TuMV biological host type [B]. Whole genome sequences of seven of the Australian isolates were obtained and had lengths of 9834 nucleotides (nt). When they were compared with 37 non‐recombinant TuMV genomes from other continents and another whole genome from Australia, six of them formed an Australian group within the overall world‐B phylogenetic grouping, while the remaining new genome sequence and the additional whole genome from Australia were part of the basal‐B grouping. When the seven new Australian genomes and the additional whole genome from Australia were subjected to recombination analysis, six different recombination events were found. Six genomes contained one or two recombination events each, but one was non‐recombinant. The non‐recombinant isolate was in the Australian grouping within the overall world‐B group while the remaining recombinant isolates were in the basal‐B and world‐B phylogenetic groups.  相似文献   

15.
 从河北、北京、山东泰安和潍坊等地区的萝卜、大白菜、甘蓝、油菜上得到8个芜菁花叶病毒(Turnip mosaic virus,TuMV)分离物,测定了它们3'-末端cDNA片段的序列。根据衣壳蛋白基因(cp)核苷酸序列可以将这8个分离物与另外2个TuMV分离物分为3组:泰安旧镇大白菜(JZBC)、甘蓝(JZGL)和萝卜(JZLB)分离物为一组;北京(BJILB)、潍坊萝卜分离物(WFLB)与引起萝卜红心病的TuMV分离物(WFLB99)为一组;泰安范镇、河北、潍坊(WFLB04)萝卜和泰安旧镇油菜(JZYC)上的TuMV分离物为一组。农壳蛋白氨基酸序列比较结果与此基本一致,所不同的是分离物WFLB99与所有分离物的差异均较大,形成单独一个分支。有必要对TuMV的变异情况和致病机理进行深入研究。  相似文献   

16.
Pepino mosaic virus (PepMV) was shown to be efficiently transmitted between tomato plants grown in a closed recirculating hydroponic system. PepMV was detected in all plant parts after transmission via contaminated nutrient solution using ELISA, immunocapture RT‐PCR, RT‐PCR, electron microscopy, and by inoculation to indicator plants. Detection of PepMV in nutrient solution was only possible after concentration by ultracentrifugation followed by RT‐PCR. Roots tested positive for PepMV 1–3 weeks after inoculation, and subsequently a rapid spread from the roots into the young leaves and developing fruits was found within 1 week. PepMV was only occasionally detected in the older leaves. None of the infected plants showed any symptoms on fruits, leaves or other organs. Pre‐infection of roots of tomato cv. Hildares with Pythium aphanidermatum significantly delayed PepMV root infections. When mechanically inoculated with PepMV at the 2–4 leaf stage, yield loss was observed in all plants. However, only plants of cv. Castle Rock recorded significant yield losses when infected via contaminated nutrient solution. Yield losses induced by infection with PepMV and/or P. aphanidermatum ranged from 0·4 up to 40% depending on experimental conditions.  相似文献   

17.
甜菜花叶病毒病的研究Ⅰ.病毒的分离鉴定   总被引:1,自引:0,他引:1  
 1986-1987年对黑龙江、内蒙古部分甜菜原料产区与采种区进行了初步调查,采种区甜菜花叶病毒病发病率达100%,与其邻近的原料产区有零星发病,远离采种区则没有发病的迹象。田间采集的病叶,用磨擦、蚜传接种方法均能在甜菜上再现症状。经昆诺藜(Chenopodium quinoa)分离,普通电镜及乳胶电镜负染均能看到典型的马铃薯Y组病毒的粒体。通过鉴别寄主、甜菜上的症状表现,分离物的物理特性及血清学试验,证明此分离物为甜菜花叶病毒。在提纯方面,摸索了不同方法,认为匀浆前液氮或冷冻处理,二次PEG沉淀后过Sepharose4B柱,分离病毒效果较好,还可省去超速离心步骤。以内蒙五号甜菜品种作为毒源的繁殖寄主,能使提纯病毒产量达0.6mg/100g叶片,耳静脉与多点皮下注射相结合免疫兔子,微量沉淀测定效价为1:1024。  相似文献   

18.
Twenty plants of alfalfa cv. Beaver were screened for resistance to alfalfa mosaic virus (AIMV) severe strain A-515. ELISA screening on both inoculated and apical leaves at fixed temperature (20°C day, 16°C night) suggested the following three types of clonal response to AIMV infection: extremely resistant, AIMV not normally detected from either inoculated or apical leaves; resistant, AIMV detected from inoculated leaves only and did not spread systemically; susceptible, AIMV detected from both inoculated and apical leaves. When plants in the second category were maintained at high temperature (30°C), AIMV was detected from inoculated and apical leaves 6 and 12 days after inoculation, but was not detectable in the apical leaves thereafter. Plants in the first category remained extremely resistant at all temperatures tested. The results of comparative tests using progeny plants of extremely resistant, resistant and susceptible plants, and of their hybrids, suggested that the resistance to AIMV A-515 was controlled by a temperature-dependent recessive gene.  相似文献   

19.
20.
Mild-strain cross protection was used in field trials at Wellesbourne and in Jersey in attempts to protect courgette plants against severe strains of zucchini yellow mosaic virus. Test plants were sap inoculated with the mild strain and then challenged by an aphid-transmitted severe strain after different periods. Approximately 14 days of incubation were required following mild-strain inoculation to provide protection against subsequent infection by severe strains. No protection occurred if severe strains were introduced 2 days (48 h) after mild-strain inoculation and protection was intermediate if the severe-strain challenge occurred after 7–8 days. Some breakdown in protection occurred in the later stages of the trial at Wellesbourne, but not in Jersey. This loss of protection may be associated with high inoculum pressures.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号