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1.
Twenty-four isolates of maize streak virus (MSV) derived from maize, sugarcane and grasses were compared to a maize isolate of the virus (M(N)M) from Nigeria, using symptoms, gel diffusion and ELISA. Fourteen isolates were identified as maize strains, eight other isolates were serologically related to M(N)M but were distinct. In most cases the maize strain could be identified by the symptoms in Zea mays cv. Golden Bantam but symptom expression in grasses was not always sufficient to identify the economically important maize strain. In general, however, symptoms were similar in both grass and maize hosts. Identification by symptoms alone was further complicated by the possibility that some isolates were mixtures. There was no evidence that adaptation to grass hosts occurred, as all isolates could be transmitted to maize. It was not possible to transmit certain strains to the host species from which they were derived, even though they were transmissible to other hosts. This was assumed to be related to vector feeding behaviour. Insect toxin was responsible for certain stunting symptoms, leaf curling and vein enations often associated with MSV. 相似文献
2.
ABSTRACT We devised a rapid technique for the objective and precise assessment of both the pathogenicity of maize streak virus (MSV) isolates and the MSV resistance of maize genotypes. The technique involves the use of agroinoculation to infect maize seedlings and the objective symptom evaluation by quantification of infection rates, stunting, and chlorotic leaf areas. In assessing the MSV resistance of 19 maize genotypes, we describe how the use of differentially virulent virus isolates enables the analysis of MSV resistance phenotypes, ranging from extremely susceptible to completely immune. We further demonstrate how quantification of chlorotic leaf areas by image analysis permits differentiation between degrees of MSV resistance that are indistinguishable from one another using currently employed symptom assessment approaches. Using chlorotic area measurements, we quantify the virulence of a diverse group of 10 MSV isolates and, through agroinoculation of differentially susceptible maize genotypes, we demonstrate the use of our technique in evaluating the pathogenicity of these isolates. 相似文献
3.
ABSTRACT Maize streak virus (MSV) is best known as the causal agent of maize streak disease. However, only a genetically uniform subset of the viruses within this diverse species is actually capable of producing severe symptoms in maize. Whereas these "maize-type" viruses all share greater than 95% sequence identity, MSV strains isolated from grasses may share as little as 79% sequence identity with the maize-type viruses. Here, we present the complete genome sequences and biological characterization of two MSV isolates from wheat that share approximately 89% sequence identity with the maize-type viruses. Clonal populations of these two isolates, named MSV-Tas and MSV-VW, were leafhopper-transmitted to Digitaria sanguinalis and a range of maize, wheat, and barley genotypes. Whereas the two viruses showed some differences in their pathogenicity in maize, they were both equally pathogenic in D. sanguinalis and the various wheat and barley genotypes tested. Phylogenetic analyses involving the genome sequences of MSV-Tas and MSV-VW, a new maize-type virus also fully sequenced in this study (MSV-VM), and all other available African streak virus sequences, indicated that MSV-Tas and MSV-VW are close relatives that together represent a distinct MSV strain. Sequence analyses revealed that MSV-VM has a recombinant genome containing MSV-Tas/VW-like sequences within its movement protein gene. 相似文献
4.
M. Angeles Achon Marion Pinner Vicente Medina George P. Lomonossoff 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(7):697-705
Two isolates of maize dwarf mosaic virus (MDMV-Sp and MDMV-Spl) obtained from maize in the northeast of Spain were studied. Both isolates induced similar reactions on 6 sorghum cultivars, johnsongrass and oat (cv. Clintland), with the exception of MDMV-Sp which produced a different reaction on one sorghum cultivar. Thirty-three grass species were tested as possible hosts (16 previously untested) and 18 were found to be susceptible. Among those, eight were previously unidentified hosts for MDMV:Aegilops ovata, A. ventricosa, Avena barbata, Bromus alopecurus, B. diandrus, B. fasciculatus, Echinaria capitata andLolium rigidum. Both isolates were transmitted from maize to maize nonpersistently byRhopalosiphum maidis, R. padi, Schizaphis graminum andSitobium avenae. The virus was not seed-transmitted in Mo17 and B73 maize inbred lines. Pinwheels, scrolls and short curved laminated aggregates were observed in the cytoplasm of maize cells infected by MDMV-Sp or MDMV-Sp1. In addition, laminated aggregates were observed in cells infected by MDMV-Sp1. 相似文献
5.
陕西玉米病毒病及流行因素研究 总被引：5，自引：0，他引：5
研究结果表明:陕西玉米病毒病毒原主要有玉米矮花叶病毒B株系(MDMV-B)、玉米粗缩病毒(MRDV)和大麦黄矮病毒(BYDV)。用血清鉴定225份病株样品中,MDMV-B、MRDV和BYDV侵染分别占40%、23%、4.5%。MDMV-B和MRDV复合侵染占23.5%。在田间自然条件下,MDMV-B主要通过玉米蚜和禾谷缢管蚜以非持久性传播,MRDV则由灰飞虱以持久传播。MDMV-B、MRDV和BYDV的粒子大小分别为735~755 nm×17 nm、70~75 nm和23~30 nm。随着玉米生育成熟,侵染逐渐降低,为害亦趋减轻。研究认为,玉米品种、播种期、播量、田间传毒介体数量及发生早晚和地膜覆盖等是影响玉米病毒病流行的主要因素。 相似文献
6.
Redinbaugh MG Seifers DL Meulia T Abt JJ Anderson RJ Styer WE Ackerman J Salomon R Houghton W Creamer R Gordon DT Hogenhout SA 《Phytopathology》2002,92(11):1167-1174
ABSTRACT A previously uncharacterized virus was isolated from fall-planted sweet corn (Zea mays L., Syngenta GSS 0966) leaves showing fine chlorotic streaks. Symptomatic plants were negative in enzyme-linked immunosorbent assay against many maize viruses, but reacted weakly with antisera to Sorghum stunt mosaic virus suggesting a distant relationship between the viruses. The virus was readily transmitted by vascular puncture inoculation (VPI), but not by leaf-rub inoculation. Symptoms on maize included dwarfing and fine chlorotic streaks along intermediate and small veins that developed 12 to 17 days post-VPI. The isolated virus was bacilliform (231 +/- 5 nm long and 71 +/- 2 nm wide), with a knobby surface, and obvious helical structure typical of rhabdovirus morphology. Nucleorhabdovirus virions were observed by transmission electron microscopy of infected maize leaf tissue sections. Proteins unique to infected plants were observed in extracts of infected leaves, and the isolated virion contained three proteins with molecular masses 82 +/- 2, 50 +/- 3, and 32 +/- 2 kDa. Preliminary sequence analysis indicated the virus had similarity to members of the family Rhabdoviridae. The virus was transmitted by Graminella nigrifrons under persistent conditions. The data indicate the virus, provisionally designated Maize fine streak virus, is a new species in the genus Nucleorhabdovirus. 相似文献
7.
Lett JM Granier M Hippolyte I Grondin M Royer M Blanc S Reynaud B Peterschmitt M 《Phytopathology》2002,92(1):65-74
ABSTRACT Spatial and temporal distribution of Maize streak virus (MSV, family Geminiviridae, genus Mastrevirus) was monitored in the vector species Cicadulina mbila and the nonvector species C. china? using conventional and real-time quantitative polymerase chain reaction. Sustained feeding on MSV-infected plants showed that virus accumulation reaches a maximum in C. china?, but not in C. mbila. After a 3-day acquisition access feeding period (AAP), MSV was detected in the gut, the hemolymph, and the head of C. mbila, but only in the gut of C. china?. Similarly, Digitaria streak virus (genus Mastrevirus), which is not transmitted by either of the two species, was only detected in the gut. MSV was detected in the hemolymph of C. mbila 3 h after the beginning of the AAP. Although viral DNA progressively decreases in the vector and nonvector species after a 3-day AAP, MSV DNA remained stable in the salivary glands of C. mbila. 相似文献
8.
ABSTRACT Water exits from inside the leaf through transpiration or guttation. Under conditions to promote guttation, surface fluid (guttation fluid) from Brome mosaic virus (BMV)-infected barley, wheat, and maize plants was analyzed for the presence of the virus by biological and serological assays. We also investigated the route by which BMV exited infected cells to the intercellular space of the barley leaf. BMV was detected in guttation fluid from systemically infected barley leaves when the initial viral symptoms were observed on these leaves. The virus was also detected in guttation fluid from systemically infected wheat leaves, but not in maize leaves showing either systemic necrosis or chlorotic streaks. Interestingly, in BMV-infected barley leaves, but not in maize leaves showing chlorotic streaks, cell death occurred within and adjacent to veins. Staining of xylem and phloem networks in infected barley leaves with fluorescent dyes showed that xylem, and to a lesser extent phloem, were severely damaged and thus became leaky for dye transport. No such damage was observed in BMV-infected maize leaves showing chlorotic streaks. We propose that in infected barley leaves, BMV exits from damaged vein cells (especially the xylem elements), accumulates in intercellular spaces, and then reaches the surface of the leaves through stomata during guttation or transpiration. In nature, BMV may be carried to adjacent plants and cause infection by movement of vertebrate and invertebrate vectors among infected plants exuding guttation fluid. 相似文献
9.
A. Alfaro‐Fernández V. Medina M. C. Córdoba‐Sellés M. I. Font J. Jornet M. C. Cebrián C. Jordá 《Plant pathology》2010,59(2):231-239
Optical and electron microscopy studies were carried out to investigate the cytopathology induced in tomato leaves infected by Tomato torrado virus (ToTV), a new picorna‐like virus associated with the ‘Torrado’ disease. Infected leaves, showing typical Torrado disease symptoms were surveyed in commercial greenhouses in the main tomato production areas of Spain. The effect of the co‐infection of ToTV with other viruses which commonly infect tomato crops was also studied. Ultra‐thin sections of ToTV‐infected tomato leaves did not show a strong cellular alteration. However, crystalline arrays of isometric virus‐like particles (VLPs) of 20–30 nm in the inclusion bodies were observed in phloem parenchyma cells of the infected tissues. Tissues co‐infected by ToTV and either Tomato chlorosis virus (ToCV) or Pepino mosaic virus (PepMV) presented more severe cellular alterations. The most deleterious consequences for tomato cells were found in triple infections of ToTV, PepMV and Tomato spotted wilt virus (TSWV), where characteristic cell wall overgrowth was distinguishable, together with a large amount of necrotic cells. 相似文献
10.
感染土传小麦花叶病毒的小麦花叶病的电子显微镜研究 总被引：2，自引：0，他引：2
经对山东省崂山地区获得的自然感病的小麦病叶进行了电镜的观察和研究。指出在早春时节小麦返青以后很快开始显示症状,沿叶脉出现短的褪绿色条纹,植株生长受阻,矮缩,黄化以至不能抽穗。该病毒粒子为细长的杆状,长度120~270nm,直径为18~20nm。值得注意的是在狭窄的胞质区可经常见到聚集的病毒颗粒,其中大部分病毒附着在膜结构上。当横切时病毒颗粒呈电子透明的空心,围绕这个空心周围是一个着色很深的直径约为10nm的核酸环,围绕这个核酸环周围是一个密度不大的蛋白外壳。病毒颗粒的聚集大多与很多弯曲的管状物的形成聚集相伴随着。也看到了完全由病毒颗粒所组成的晶体状聚集物。根据以上所述,该病原鉴定为土传小麦花叶病毒。 相似文献
11.
Elliot W KITAJIMA Hideki KONDO Anne MACKENZIE Jorge Alberto M REZENDE Ricardo GIORIA Adrian GIBBS Tetsuo TAMADA 《Journal of General Plant Pathology》2001,67(3):231-237
Cytopathic effects in orchid leaf tissues infected with Australian, Japanese and Brazilian isolates of Orchid fleck virus
(OFV) were indistinguishable and like those previously described in the literature. Cells had an electron-lucent viroplasm
with unenveloped rod-shaped virions in the nucleus and cytoplasm, often associated with the inner membrane of the nuclear
envelope and the endoplasmic reticulum. Antiserum raised against a Japanese isolate of OFV reacted with Brazilian and Australian
isolates in ELISA, and when used for immuno-gold labelling, also reacted in situ with the rod-shaped virions and the intranuclear viroplasm of all three isolates. These results suggest that the viroplasm
is where structural proteins accumulate and virions are formed.
Received 13 December 2000/ Accepted in revised form 13 April 2001 相似文献
12.
A virus having tubular particles (124, 142 and 167 nm) was manually transmitted from and to Anthoxanthum odoratum (sweet vernal grass). Other experimental hosts were Chenopodium quinoa, C. amaranticolor, Zea mays, Avena sativa and Hordeum vulgare (barley); winter cultivars of barley were more often infected than spring cultivars. In tests which simulated mechanical injury, the virus was transmitted from infected to healthy A. odoratum but not to healthy barley. The virus particles, which were seen as aggregates in the cytoplasm of A. odoratum leaf cells and in anther walls, reacted strongly in immunosorbent electron microscopy tests with antisera to strains of barley stripe mosaic hordeivirus. Nevertheless, the virus could be distinguished from the Type strain of barley stripe mosaic virus by reciprocal serological tests and by symptoms in infected barley cv. Black Hulless. Using an antiserum produced against the virus, a survey of A. odoratum in the field revealed one of 72 tested plants to be naturally infected. The virus is probably that described by Catherall & Chamberlain (1980) and named anthoxanthum latent blanching virus. 相似文献
13.
小麦梭条斑花叶病毒(WSSMV)和小麦黄花叶病毒(WYMV)的细胞质内含体的电镜观察 总被引：3，自引：0，他引：3
小麦梭条斑花叶病毒(WSSMV)和小麦黄花叶病毒(WYMV)分别感染小麦(Triticum aestivum L.)后所诱发的细胞质内含体和细胞嚣病变几乎完全相同。感病的叶肉细胞、表皮细胞和木质部薄壁细胞的细胞质中都可看到大量风轮体、柱状体、板状集结体和膜状体,其中以叶肉细胞中更为普遍。风轮体成群出现、同一组内风轮体常平行排列,而相邻群间常垂直排列。膜状体的内部常夹杂着许多小囊泡,其四周与内质网呈辐射状相连。在发病初期的心叶叶肉细胞质的液泡附近可看到颗粒状病毒束,而分散的病毒状颗粒则多见于发病中后期坏死的细胞中。感病细胞的叶绿体、线粒体、核、质膜及胞间联丝中均未见病毒状颗粒。感染病毒的细胞中,细胞质丰富、内质网膨大,核糖体增加、小囊泡大量出现,随着病害的加重,叶绿体、线粒体逐渐肿大,基粒缩小、膜破裂、类囊物流入细胞中。 相似文献
14.
Abstract A preliminary survey was made in the most important maize‐growing regions of Ethiopia to record the species of Cicadulina present, their distribution and abundance. Five species of Cicadulina were found, including two not previously reported from Ethiopia. The maize strain of maize streak geminivirus (MSV) occurred predominantly between 450 and 1800 m above sea level, which coincides with the altitudinal range of C. mbila implicating this species as the principal vector of MSV in Ethiopia. The maize strain isolate was indistinguishable from others from elsewhere in Africa. 相似文献
15.
16.
17.
Interactions among maize streak virus disease, leafhopper vector populations and maize cultivars in forest and savanna zones of Nigeria 总被引：1，自引：0，他引：1
C. M. ASANZI N. A. BOSQUE-PEREZ I. W. BUDDENHAGEN D. T. GORDON L. R. NAULT 《Plant pathology》1994,43(1):145-157
Monthly plantings of three maize cultivars with differing resistance/susceptibility to maize streak geminivirus (MSV) and samplings of Cicadulina leafhopper vectors were made from December 1988 to April 1990 in the humid forest and from May to November 1989 in the Guinea savanna zones of Nigeria. High MSV disease incidences (43–56%) were recorded on susceptible cultivar TZB-Gusau in late-season (July-October) plantings. Hybrid 8321-21 showed significantly lower MSV disease incidence and severity than the other two cultivars, TZB-Gusau and 8329-15. Cicadulina species population peaks (5.2-13.5 leafhoppers/m2 ) were observed before the rains ended in savanna locations and after the end of the rains in the forest zone. Cicadulina mbila was the predominant species, whereas C. storeyi (syn. C. triangula ), C. arachidis, C. similis and C. ghaurii were less common. The proportion of viruliferous leafhoppers increased as the season progressed, reaching maxima of 15–25% at the end of the growing season. Interactions between disease incidence, Cicadulina populations, maize cultivars and rainfall are discussed. 相似文献
18.
ABSTRACT When two unrelated plant viruses infect a plant simultaneously, synergistic viral interactions often occur resulting in devastating diseases. This study was initiated to examine ultrastructural virus-virus interactions of mixed viral infections. Mixed infections were induced using potyviruses and viruses from other plant virus families. Novel ultrastructural paracrystalline arrays composed of co-infecting viruses, referred to as mixed virus particle aggregates (MVPAs), were noted in the majority of the mixed infections studied. When the flexuous rod-shaped potyvirus particles involved in MVPAs were sectioned transversely, specific geometrical patterns were noted within some doubly infected cells. Although similar geometrical patterns were associated with MVPAs of various virus combinations, unique characteristics within patterns were consistent in each mixed infection virus pair. Centrally located virus particles within some MVPAs appeared swollen (Southern bean mosaic virus mixed with Blackeye cowpea mosaic virus, Cucumber mosaic virus mixed with Blackeye cowpea mosaic virus, and Sunn hemp mosaic virus mixed with Soybean mosaic virus). This ultrastructural study complements molecular studies of mixed infections of plant viruses by adding the additional dimension of visualizing the interactions between the coinfecting viruses. 相似文献
19.
C. Ferreiro K. Ostrówka J. J. López-Moya J. R. Díaz-Ruíz 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(8):779-786
Two peanut stunt virus isolates from Poland (PSV-Ag and PSV-P) have been studied. The isolates produce similar systemic symptoms onNicotiana tabacum plants but the symptoms onN. benthamiana, Pisum sativum andDatura stramonium plants are much stronger for the PSV-P isolate. Analysis of the RNA extracted from purified virions by gel electrophoresis and RT-PCR amplification allowed the detection of a satellite RNA in the PSV-P isolate. The nucleotide sequence of this European PSV satellite was determined and found to have a high degree of identity with the sequences of the four American PSV satellites previously studied, which were found to have either no effect or ameliorate the PSV symptoms in tobacco plants (Collmer et al., 1985; Naidu et al., 1991). The possible role of the European PSV satellite in the modulation of viral symptoms has been studied but no effect was observed when the purified satellite was used with the PSV-Ag isolate as helper virus on any of the three hosts cited above. 相似文献