共查询到20条相似文献，搜索用时 31 毫秒
1.
P. L. GUY 《Plant pathology》1993,42(1):1-5
Pasture grasses from temperate Japan were tested for infection with barley yellow dwarf viruses (BYDVs) and fungal endophytes. BYDVs from both the MAV and RPV subgroups were detected, but no symptoms attributable to BYDV infection were observed. Not all isolates from the MAV subgroup could be clearly discriminated as MAV or PAV solely on ELISA results, and may have been intermediate serotypes or mixed infections. BYDVs were found to infect fescue ( Festuca arundinacea : 17%), ryegrass ( Lolium perenne : 41%), timothy ( Phleum pratense : 94%) and Poa spp. (20%). Fescue and ryegrass were predominantly infected with RPV and PAV, respectively. The small collections of Poa spp. were only infected with PAV, while timothy was only tested for MAV subgroup viruses. In fescue 26% of tillers were infected with Acremonium coenophialum , and 60% of ryegrass tillers from an ecotype collection were infected with Acremonium lolii. There was no correlation between BYDV infection and the presence of endophytes for the above species or for Epichloe typhina -infected (50%) timothy. An ELISA test for A. lolii did not detect A. coenophialum in fescue or E. typhina in timothy but showed good agreement with epidermal staining of A. lolii in ryegrass leaf sheaths. 相似文献
2.
ABSTRACT Population dynamics of Padi avenae (PAV), Macrosiphum avenae (MAV), and Rhopalosiphum padi (RPV) virus serotypes of Barley yellow dwarf virus (BYDV) and of their main aphid vectors were studied in winter barley (Hordeum vulgare) fields for three successive years in western France. An epidemiological model of the spread of viruses in the field was developed based on vector populations as forcing variables and the population dynamics of each virus serotype. This model accurately simulated the kinetics of the epidemic for PAV serotypes, which are the most common ones. For RPV and to some extent for MAV, the results were less satisfactory. The occurrence and spread of PAV and MAV serotypes in the field was clearly and easily related to that of their main vector species. Conversely, the spread of RPV serotypes showed no consistent relationships with the dynamics of their vectors. Incidence of PAV in 1989 to 1990 and 1990 to 1991 showed a bimodal distribution, with maximums in fall (December) and spring (May) that were linked to fall infestations by R. padi and spring infestations by three (R. padi, Sitobion avenae, and Metopolophium dirhodum) or two (S. avenae and M. dirhodum) aphid species. In 1991 to 1992, the PAV infection curve was monomodal and mainly due to a primary spread of the virus by very large populations of alate R. padi. MAV incidence was low in fall and winter and reached a maximum in spring 1990 and 1991 related to the occurrence of S. avenae and M. dirhodum. RPV incidence was low every year, despite the abundance of its vector, R. padi. Mixed infections were more frequent than expected by chance and were assumed to be partly related to heterologous encapsidation. The occurrence of each serotype is discussed in relation to the time of crop infection and possible damage. 相似文献
3.
South Australia is in the dry temperate zone where most cereal crops are grown in an area of low rainfall, with a crop-free season from December to April. The incidence of barley yellow dwarf virus (BYDV) was assessed by ELISA from 1989 to 1991 in wheat crops and irrigated pastures of South Australia. The incidence of BYDV was low in most wheat crops of the low-rainfall area in 1989 and 1990 (less than 1% of plants infected), but moderate levels of infection (1–10%) were observed in some early-sown crops. BYDV infection was more widespread in the high-rainfall area (south east of South Australia). A high incidence of BYDV was observed in the irrigated pastures of the three areas surveyed (4–86%). Of the five previously described strains, the Rhopalosiphum padi/Sitobion avenae strain (PAV) was the most common in wheat samples (> 90%). PAV and the R. padi-specific strain (RPV) were found in pasture grasses, alone or in mixed infection. Virus incidence was greater in Festuca spp. (56%) and Lolium perenne (30%) than in other species (2-–9%). 相似文献
4.
Barley yellow dwarf virus in ryegrass and its detection by ELISA 总被引：6，自引：6，他引：0
S. J. I. HOLMES 《Plant pathology》1985,34(2):214-220
The enzyme-linked immunosorbent assay (ELISA) effectively detected PAV- and MAV-like strains of barley yellow dwarf virus (BYDV) in ryegrass. MAV-like BYDV was found in a large proportion of ryegrass plants with foliar symptoms. There was a poor association between foliar symptoms and PAV-like virus, which occurred with similar frequency in plants with and without symptoms. By August 1982, plots of perennial, Italian and hybrid ryegrass sown at Auchincruive in 1980 were extensively infected with PAV- and MAV-like strains of BYDV. Tests on samples from 1981- and 1982-sown plots in August 1983 also indicated early invasion by BYDV. Infection levels of 7–80% were found in 13 commercial crops of perennial ryegrass surveyed near Auchincruive in May 1983. PAV-like BYDV occurred with greater frequency than did MAV-like strains of the virus. 相似文献
5.
Effects of barley yellow dwarf and ryegrass mosaic viruses alone and in combination on the productivity of perennial and Italian ryegrasses 总被引：2，自引：2，他引：0
P. L. CATHERALL 《Plant pathology》1987,36(1):73-78
Moderately severe strains of barley yellow dwarf virus (BYDV) and ryegrass mosaic virus (RMV) significantly reduced the heights and yields of perennial ( Lolium perenne ) and Italian (L. multifiorum) ryegrasses. BYDV caused greater reductions in perennial ryegrass than in Italian, whereas the converse was true of RMV. Both viruses together rarely caused greater damage than the most damaging virus on its own. BYDV reduced the aggressiveness of perennial ryegrass more than of Italian, whereas with RMV the converse was true. In mixtures of perennial and Italian ryegrasses, the perennial was suppressed by the Italian when only BYDV was present, the Italian was suppressed by the perennial when only RMV was present, and the status quo was maintained when both viruses were present, even though they reduced the yield of the mixture by over 16%. 相似文献
6.
The incidence and distribution of aphid transmitted barley yellow dwarf (BYD) viruses (PAV-, RPV- and MAV-like isolates) are described in 14 species of common pasture and hedgerow grasses from five localities of south-west England during 1987 and 1988. Isolates were identified by indirect 'sandwich' ELISA using the monoclonal antibodies MAC91, MAC92 and MAFF2. More infection was detected in 1987 than in 1988 but this was mainly due to a sharp decline at one site. Intensity of infection was greater in Poa annua and Lolium perenne populations than in most other species. BYD was not detected in Arrhenatherum elatius Elymus repens Agrostis canina and A. stolonifera . All three isolates of BYD were widespread. MAV was associated more with localities further north and RPV more with those further south. PAV was common only at the southern-most site. This geographical distribution was reasonably consistent in both years. Given these trends, susceptible grass species fell broadly into three groups with respect to isolate frequency, those predominently infected by RPV and MAV (seven spp.), those equally infected by all isolates (two spp.) and a single species, Poa annua , infected mainly by PAV. Some implications of these findings for the epidemiology and control of BYD viruses are briefly considered. 相似文献
7.
As pasture grasses are preponderant in the agriculture of western France, their role as reservoirs of barley yellow dwarf virus (BYDV) and its aphid vectors has been studied from 1984 to 1986. Aphids were observed on most crops of five pasture grass species (brome grass, cocksfoot, tall fescue, Italian and perennial ryegrass) but in very low numbers. Rhopalosiphum padi was the most numerous species. The incidence of BYDV was high, with levels of infection ranging from 6 to 80% depending on the species of pasture grasses. Fescue pastures were highly infected with BYDV, whereas the virus was not detected in cocksfoot pastures. PAV-, RPV-, MAV-like isolates of BYDV were detected in pasture grasses, but RPV- and MAV-like isolates were only detected from ryegrass and brome grass, respectively. The role of these grasses as source of viruliferous aphids infecting cereals is discussed. 相似文献
8.
ABSTRACT A large epidemiological study of the genetic variation of barley yellow dwarf virus (BYDV) serotype PAV involving different host plant species was conducted. French BYDV PAV isolates were collected from barley and ryegrass, and their capsid protein gene sequences characterized using restriction fragment length polymorphism, single-strand conformation polymorphism, and sequence analyses. The data show that BYDV PAV isolates from five different continents are separated into two distinct groups named cpA and cpB, which are distributed irrespective of geographical location. Amino acid identity of the capsid proteins ranged from 93 to 99.5% in group cpA and from 95 to 99.5% in group cpB, while this value was only from 82 to 88% between the groups. Moreover, isolates from each group were found preferentially (up to 98%) in one of the two plant species examined. These results show that host plant species play a role in isolate selection and maintenance and that they contribute to the genetic diversity of BYDV PAV. 相似文献
9.
The incidence of barley yellow dwarf virus isolates in perennial ryegrass (Lolium perenne) in south-western Victoria 总被引：3，自引：3，他引：0
Barley yellow dwarf virus (BYDV) was detected in perennial ryegrass cultivars examined from three sites in south-western Victoria (Balmoral, Mininera and Hamilton); the frequency of BYDV infection varied with cultivar. PAV-related isolates were prevalent at all sites, but the incidence of MAV- and RPV-related isolates varied with the site and cultivar. The PAV-related isolate was less frequent in cv. Ellett than in cv. Victorian at all sites. The implications for the epidemiology of the disease and its agronomic importance in Victoria are discussed. 相似文献
10.
P. L. GUY 《Plant pathology》1988,37(4):546-550
Samples of cocksfoot ( Dactylis glomerata ), fescue ( Festuca arundinacea ), phalaris ( Phalaris aquatica ) and ryegrass ( Lolium perenne ) were collected every 4-6 weeks for 2.5 years from two sets of replicated plots, one on a heavy soil and the other on a light soil 200 m away. Rhopalosiphum padi was the predominant aphid species; it was more frequent at the heavy soil site. Sitobion fragariae and Metopolophium dirhodum occurred infrequently during the last 12 months of the survey.
Only PAV (57%), RPV (26%) and mixed infections (17%) of these barley yellow dwarf viruses were detected in the 4100 tillers sampled. Virus incidence increased over the sampling period and was consistently higher at the heavy soil site. RPV only became frequent during the last 12 months.
Virus incidence was higher in fescue (21%) and ryegrass (27%), in which PAV predominated, than in cocksfoot (6%) and phalaris (7%), in which RPV finally predominated. 相似文献
Only PAV (57%), RPV (26%) and mixed infections (17%) of these barley yellow dwarf viruses were detected in the 4100 tillers sampled. Virus incidence increased over the sampling period and was consistently higher at the heavy soil site. RPV only became frequent during the last 12 months.
Virus incidence was higher in fescue (21%) and ryegrass (27%), in which PAV predominated, than in cocksfoot (6%) and phalaris (7%), in which RPV finally predominated. 相似文献
11.
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
12.
晋南冬麦区大麦黄矮病毒流行株系监测及防治策略探讨 总被引：2，自引：0，他引：2
连续5年(1996～2000年)采集晋南冬麦区小麦黄矮病标样,采用生物学和血清学(酶联免疫吸附法)相结合的诊断方法对该地区的大麦黄矮病毒流行株系进行了鉴别。结果表明,该小麦黄矮病流行区近五年以GAV株系为主流株系,兼有少量GPV、PAV和混合株系存在。同时对小麦抗黄矮病新品种“临抗1号”进行了GPV和GAV两种株系的抗性测定,明确了该品种兼抗GPV和GAV两种株系。根据小麦黄矮病发生现状,提出了一套以选育推广抗耐病品种为主,以药剂防治为辅的综合防治措施。以期为当地小麦生产服务。 相似文献
13.
14.
Surveys were conducted during the cool-dry months of June–August 1997 and June–July 1998 for the presence of viruses in irrigated wheat in Central, Copperbelt, Lusaka and Southern Provinces of Zambia in 14 commercial farms and four wheat cultivar plots. Virus symptoms were observed on nine wheat cultivars ( Triticum aestivum 'Deka', 'Gamtoos', 'Lorie II', 'MM2', 'Nata', 'Nkwazi', 'P7', 'Scan' and 'Sceptre') of South African, Zambian and Zimbabwean origin. Several viruses were identified on the basis of field symptomatology, symptoms developing on mechanically inoculated indicator plant species or cultivars and serology (DAS-ELISA). The study revealed the occurrence of Brome mosaic virus (BMV), Barley stripe mosaic virus (BSMV), Barley yellow dwarf virus and its strains (BYDV-PAV and RPV), Soil-borne wheat mosaic virus (SBWMV), Wheat dwarf virus (WDV), Wheat streak mosaic virus (WSMV) and Wheat spindle streak mosaic virus (WSSMV). DSA-ELISA tests confirmed these identifications. The prevalence of viruses varied annually and from field to field. BSMV, BYDV-PAV, SBWMV, WDV, WSMV and WSSMV were found to be the most prevalent viruses. Viruses generally occurred in mixed infections of 3–6 viruses and the most common virus complex consisted of 4 viruses (50%), viz. BYDV, SBWMV, WDV and WSSMV. Five- and six-virus complexes were relatively less common (20% each) whereas 3-virus complex was noticed in only 10% cases. SBWMV and WSSMV have been found to be new to Africa and Zambia and are reportedly vectored by a fungal protist – Polymyxa graminis . BYDV strains MAV and SGV were also tested but gave negative results against their antisera. 相似文献
15.
ABSTRACT Resistance to Barley yellow dwarf virus (BYDV) is not found in wheat but is available in a Thinopyrum intermedium translocation (Ti) carried on chromosome 7DL of bread wheat recombinant lines. We used one of those lines (TC14/2*Spear) to introgress the Ti into bread wheat cultivars and to determine the influence of wheat backgrounds, with and without known tolerance to BYDV, on the expression of resistance. Two single and three backcross populations, segregating for the presence of the alien fragment, were tested under field conditions and artificial inoculation with BYDV isolates MAV-Mex and PAV-Mex. Lines containing the fragment were identified using the microsatellite marker gwm37. Tillering, biomass, grain yield, thousand-kernel weight, and seed quality were evaluated in inoculated and noninoculated plots. Resistance was assessed by enzyme-linked immunosorbent assay. In early generations, the alien fragment followed expected Mendelian segregation, whereas in the advanced ones a slight bias against its transmission was observed. No positive nor negative effects of Ti on agronomic performance and quality were found. A significant optical density reduction in individuals carrying the fragment was observed after PAV infection in crosses with lines Anza and Baviacora but not with Milan. In addition, the fragment was associated with a lower frequency of infected plants for both PAV and MAV isolates. The reduced yield loss associated with the presence of the translocation was due largely to the lower infection rate. 相似文献
16.
Characterization of wheatgrass-derived barley yellow dwarf virus resistance in a wheat alien chromosome substitution line 总被引：1，自引：0，他引：1
Anderson JM Bucholtz DL Greene AE Francki MG Gray SM Sharma H Ohm HW Perry KL 《Phytopathology》1998,88(8):851-855
ABSTRACT Wheatgrass (Thinopyrum intermedium) possesses a high level of resistance to barley yellow dwarf virus (BYDV) subgroup I and subgroup II strains. A wheat line (P29), in which the 7D chromosome has been substituted with a group 7 chromosome from T. intermedium, was examined for the level of resistance to two subgroup I and two subgroup II BYDV strains. In P29 plants inoculated with the subgroup I PAV strains, the titer of virus in leaf and stem tissue was typically reduced 42 to 52% when compared with the BYDV-susceptible cv. Abe. P29 and 'Abe' had the same content of PAV in roots. These results and the absence of detectable virus in inoculated T. intermedium plants indicate that the complete resistance to subgroup I possessed by the wheatgrass has not been introgressed into P29. In contrast, P29 was completely resistant throughout the plant to the subgroup II strains, NY-RPV and NY-RMV, demonstrating that the complete resistance to subgroup II in T. intermedium was incorporated into P29. Further analysis of this resistance to NY-RPV showed that NY-RPV can replicate in mesophyll protoplasts of P29 and 'Abe', suggesting that this resistance is not operating at the single-cell level. Molecular marker analysis confirmed that the T. intermedium chromosome present in P29 is a different group 7 wheatgrass chromosome than that present in L1, a wheat line with BYDV resistance properties similar to those of P29. 相似文献
17.
18.
P. L. GUY 《Plant pathology》1992,41(1):29-34
The perennial ryegrass endophyte Acremonium lolii occurred in all ryegrass (Lolium perenne) pastures sampled in Tasmania. Cultivars tested included Ellett, Martlet, Tasdale, Tasmanian No. 1 and Victorian. The range in incidence was 4–94% (average 66%). Many pastures more than 4 years old caused perennial ryegrass staggers syndrome in livestock, and the range in incidence in these pastures was 79–94%. There was no correlation, positive or negative, between barley yellow dwarf virus infection and the incidence of A. lolii. There was good agreement between ELISA and microscopic examination of epidermal strips. However unlike previous studies, the ELISA test was specific for A. lolii and did not detect Acremonium coenophialum , the endophyte of tall fescue. 相似文献
19.
20.
The invasive weed Ventenata dubia is a host of Barley yellow dwarf virus with implications for an endangered grassland habitat 
下载免费PDF全文
下载免费PDF全文 Ventenata dubia (African wiregrass), a winter annual weed, is a non‐native species invading grasslands, rangelands and pastures throughout the USA. Limited information is available on its suitability as a host to pathogens and insects in its invaded range. The barley/cereal yellow dwarf virus (B/CYDV) complex occurs ubiquitously in Poaceae species. In non‐managed grasslands, BYDV infection influences competitive dynamics between native and invasive grasses and facilitates invasion by non‐native annual weeds. The Palouse prairie of south‐eastern Washington and northern Idaho, USA, is an endangered ecosystem. Surveys of V. dubia in Palouse prairie and neighbouring Conservation Reserve Program (CRP) habitats were conducted to determine whether B/CYDV viral species are present. Laboratory tests examined the suitability of V. dubia to host BYDV‐PAV and serve as an inoculum source. Plant growth and weight parameters were measured to gauge the impact of BYDV‐PAV on V. dubia. Infection of V. dubia in Palouse prairie and CRP habitats with two species of BYDV, PAV and SGV, was detected for the first time. The ability of BYDV‐PAV to infect V. dubia in the laboratory and transmission from infected V. dubia to barley were demonstrated. BYDV‐PAV‐infected V. dubia showed reductions in plant height, number of leaves and tillers per plant, and above‐ground dry weight, suggesting that V. dubia is sensitive to BYDV. Results demonstrate that V. dubia is a host to BYDV and may serve as a virus inoculum source with potential implications for its management, competitive dynamics between invasive and native grasses and future conservation of endangered grasslands. 相似文献