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Yellow Mosaic Virus (yellow + mosaic_virus)
Kinds of Yellow Mosaic Virus Selected AbstractsComplete Genome Sequence of a Slovak Isolate of Zucchini Yellow Mosaic Virus (ZYMV) Provides Further Evidence of a Close Molecular Relationship Among Central European ZYMV Isolates,JOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2006M. Glasa Abstract The complete nucleotide sequence of a Slovak isolate of Zucchini yellow mosaic virus (ZYMV-Kuchyna) was determined. The viral genome contains 9593 nucleotides, excluding the poly(A) tail, and encodes a putative polyprotein of 3080 amino acid residues. All characteristic motifs of potyviral proteins' fundamental viral properties and vector transmission are conserved in the ZYMV-Kuchyna genome. The entire sequence shares identities of 90.4,98.8% and 78,98.8% with 12 sequenced ZYMV isolates at the nucleotide and amino acid levels, respectively. Phylogenetic analysis of the complete capsid protein (CP) sequences of more than 50 geographically different ZYMV isolates has shown that Central European isolates are closely related and form a phylogenetically homogeneous group. [source] Virus Resistance in Cereals: Sources of Resistance, Genetics and BreedingJOURNAL OF PHYTOPATHOLOGY, Issue 9 2009Frank Ordon Abstract In cereals, soil-borne viruses transmitted by the plasmodiophorid Polymyxa graminis (e.g., Barley mild mosaic virus, Barley yellow mosaic virus or Soil-borne cereal mosaic virus), have increased in importance due to the increase of the acreage infested and because yield losses cannot be prevented by chemical measures. Due to global warming, it is also expected that insect transmitted viruses vectored by aphids (e.g., Barley yellow dwarf virus, Cereal yellow dwarf virus), leafhoppers (Wheat dwarf virus) or mites (e.g., Wheat streak mosaic virus), will become much more important even in cooler regions. The environmentally most sound and also most cost effective approach to prevent high yield losses caused by these viruses is breeding for resistance. Therefore, in contrast to other reviews on cereal viruses, this study briefly reviews present knowledge on cereal-infecting viruses and emphasizes especially the sources of resistance or tolerance to these viruses and their use in molecular breeding schemes. [source] Biological and Molecular Variability of Zucchini yellow mosaic virus in Iran,JOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2008Kaveh Bananej Abstract Zucchini yellow mosaic virus (ZYMV; family Potyviridae, genus Potyvirus) causes high yield losses to cucurbits in many parts of the world. The virus was detected for the first time in Iran in 1988, but the isolates have not been characterized. To study the genetic and biological diversity among Iranian ZYMV isolates, a set of twelve isolates, obtained during an extensive survey conducted from 2003 to 2006 in the major cucurbit-growing areas, were characterized. An experimental host range study of these isolates (referred as Iran-1 to Iran-12) revealed some variation in their biological properties. The nucleotide sequences of the genomic portion spanning the C-terminal part of NIb and N-terminal part of coat protein (CP) coding region were determined and compared with other available sequences. The identity among Iranian ZYMV isolates at the amino acid level reached 95.6,100%. The Iranian ZYMV isolates did not form a compact cluster in the phylogenetic tree, and the phylogenetic analyses and the estimation of genetic distance indicate that the Iranian ZYMV group consists of several independent introductions that evolved separately. [source] Complete Genome Sequence of a Slovak Isolate of Zucchini Yellow Mosaic Virus (ZYMV) Provides Further Evidence of a Close Molecular Relationship Among Central European ZYMV Isolates,JOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2006M. Glasa Abstract The complete nucleotide sequence of a Slovak isolate of Zucchini yellow mosaic virus (ZYMV-Kuchyna) was determined. The viral genome contains 9593 nucleotides, excluding the poly(A) tail, and encodes a putative polyprotein of 3080 amino acid residues. All characteristic motifs of potyviral proteins' fundamental viral properties and vector transmission are conserved in the ZYMV-Kuchyna genome. The entire sequence shares identities of 90.4,98.8% and 78,98.8% with 12 sequenced ZYMV isolates at the nucleotide and amino acid levels, respectively. Phylogenetic analysis of the complete capsid protein (CP) sequences of more than 50 geographically different ZYMV isolates has shown that Central European isolates are closely related and form a phylogenetically homogeneous group. [source] Identification and Molecular Characterization of Viruses Infecting Cucurbits in PakistanJOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2004A. Ali Abstract Cucurbits are grown throughout the North-West Frontier Province of Pakistan as summer and winter crops. Plants having mosaic, mottling, chlorosis and leaf distortion symptoms were frequently found in most of the cucurbit fields during the survey. Using dot immunobinding assay, Cucumber green mottle mosaic virus (CGMMV), Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV) and Papaya ringspot virus (PRSV) were found infecting cucurbits. CGMMV was widespread, infecting 46.9% of the samples tested followed by ZYMV (14.8%), WMV (12.5%) and PRSV (7.8%). Multiple infections were common with 42% of the samples being infected with two viruses and 8% with three viruses. The nucleotide sequences of the coat protein (CP) genes of these four viruses were determined and deduced amino acid sequence comparisons revealed 88.3,99% similarity of the ZYMV-Pak isolate with other isolates of ZYMV reported worldwide. The amino acid sequence identity of Pakistani isolates of WMV, CGMMV and PRSV ranged from 96.8 to 98.4%, 98.1 to 99.4% and 79.3 to 84.2%, respectively, with other isolates reported elsewhere. Little variability was observed in the sequences of WMV and CGMMV. ZYMV-Pak was very close to the USA isolate, and the PRSV-Pak isolate was close to Indian isolates of PRSV possibly reflecting the geographical relationship between these isolates. [source] Molecular Analysis of Zucchini yellow mosaic virus Isolates from Hangzhou, ChinaJOURNAL OF PHYTOPATHOLOGY, Issue 6 2003M.-F. Zhao Abstract Isolates of Zucchini yellow mosaic virus were obtained from different cucurbit crops in Hangzhou city, China. The complete nucleotide sequences of four isolates and the 3,-terminal sequences, including the coat protein coding region, of four others were determined and then compared with other available sequences. Phylogenetic analysis of the coat protein nucleotide sequences showed that these isolates fell into three significant groups, one of which (designated group III) consisted exclusively of Chinese isolates and is reported for the first time. Comparisons over the completely sequenced genomes showed that, typically for potyviruses, the 5,-end of the genome was usually the most variable but that the group III isolate differed from the others most significantly in the N-terminal part of the coat protein. Partially sequenced group III isolates also varied from other isolates in this region. Group III isolates appear to differ biologically from the other isolates because they do not cause symptoms in watermelon fruit but induce more severe symptoms on the watermelon leaves. [source] Characterization of a novel Toll/interleukin-1 receptor (TIR)-TIR gene differentially expressed in common bean (Phaseolus vulgaris cv. Othello) undergoing a defence response to the geminivirus Bean dwarf mosaic virusMOLECULAR PLANT PATHOLOGY, Issue 2 2007YOUNG-SU SEO SUMMARY Common bean (Phaseolus vulgaris L.) cultivar (cv.) Othello develops a hypersensitive response-associated vascular resistance to infection by Bean dwarf mosaic virus (BDMV), a single-stranded DNA virus (genus Begomovirus, family Geminiviridae). A PCR-based cDNA subtraction approach was used to identify genes involved in this resistance response. Eighteen clones, potentially involved with BDMV resistance, were identified based upon being up-regulated in BDMV-infected tissues and/or having sequence similarity with known resistance-associated genes. Analysis of these clones revealed potential genes involved in pathogen defence, including pathogenesis-related protein genes and resistance gene analogues (RGAs). Further characterization of one RGA, F1-10, revealed that it encodes a predicted protein with a double Toll/interleukin-1 receptor (TIR) motif. Full-length (F1-10) and spliced (F1-10sp) forms of the RGA were strongly up-regulated in BDMV-infected cv. Othello hypocotyl tissues by 4 days post-inoculation, but not in equivalent mock-inoculated tissues. In agroinfiltration experiments, F1-10, but not F1-10sp, mediated resistance to BDMV in the susceptible common bean cv. Topcrop. By contrast, transgenic Nicotiana benthamiana lines expressing F1-10 or F1-10sp were not resistant to BDMV. Interestingly, when these transgenic lines were inoculated with the potyvirus Bean yellow mosaic virus, some F1-10 lines showed a more severe symptom phenotype compared with non-transgenic control plants. Based on these findings, F1-10 was named: Phaseolus vulgaris VIRUS response TIR-TIR GENE 1 (PvVTT1). [source] Turnip yellow mosaic virus: transfer RNA mimicry, chloroplasts and a C-rich genomeMOLECULAR PLANT PATHOLOGY, Issue 5 2004THEO W. DREHER SUMMARY Taxonomy:,Turnip yellow mosaic virus (TYMV) is the type species of the genus Tymovirus, family Tymoviridae. TYMV is a positive strand RNA virus of the alphavirus-like supergroup. Physical properties:, Virions are non-enveloped 28-nm T = 3 icosahedrons composed of a single 20-kDa coat protein that is clustered in 20 hexameric and 12 pentameric subunits. Infectious particles and empty capsids coexist in infected tissue. The genomic RNA is 6.3 kb long, with a 5,m7GpppG cap and a 3, untranslated region ending in a tRNA-like structure to which valine can be covalently added. The genome has a distinctive skewed C-rich, G-poor composition (39% C, 17% G). Viral proteins:, Two proteins, whose open reading frames extensively overlap, are translated from the genomic RNA. p206, which contains sequences indicative of RNA capping, NTPase/helicase and polymerase activities, is the only viral protein that is necessary for genome replication in single cells. It is produced as a polyprotein and self-cleaved to yield 141- and 66-kDa proteins. p69 is required for virus movement within the plant and is also a suppressor of gene silencing. The coat protein is expressed from the single subgenomic RNA. Hosts and symptoms:, TYMV has a narrow host range almost completely restricted to the Cruciferae. Experimental host species are Brassica pekinensis (Chinese cabbage) or B. rapa (turnip), in which diffuse chlorotic local lesions and systemic yellow mosaic symptoms appear. Arabidopsis thaliana can also be used. Clumping of chloroplasts and the accumulation of vesicular invaginations of the chloroplast outer membranes are distinctive cytopathological symptoms. High yields of virus are produced in all leaf tissues, and the virus is readily transmissible by mechanical inoculation. Localized transmission by flea beetles may occur in the field. [source] Molecular and biological characterization of Macroptilium yellow mosaic virus from JamaicaPLANT PATHOLOGY, Issue 3 2008I. I. Amarakoon The molecular and biological characterization of a begomovirus infecting the common weed Macroptilium lathyroides from Jamaica are reported. The virus showed 92% sequence identity to an isolate of Macroptilium yellow mosaic virus (MaYMV) from Cuba, but was distinct from the two other begomoviruses isolated from M. lathyroides, namely Macroptilium yellow mosaic Florida virus (80% identity) and Macroptilium mosaic Puerto Rico virus (68% identity). Hence, the Jamaican begomovirus was considered an isolate of MaYMV and called Macroptilium yellow mosaic virus -[Jamaica] (MaYMV-[JM]). In infectivity studies using cloned DNA-A and DNA-B genomic components, MaYMV-[JM] infected red kidney bean (Phaseolus vulgaris) and produced mild symptoms in Scotch Bonnet pepper (Capsicum chinense), but did not infect cabbage (Brassica oleracea). This information has implications for the development of strategies to control begomovirus diseases in Jamaica and elsewhere. [source] Virus impact at the interface of an ancient ecosystem and a recent agroecosystem: studies on three legume-infecting potyviruses in the southwest Australian floristic regionPLANT PATHOLOGY, Issue 5 2007C. G. Webster The southwest Australian floristic region (SWAFR) is an internationally recognized ,hot spot' of global biodiversity and has an endangered flora. It represents a unique interface between an ancient ecosystem and a recent agroecosystem, providing the opportunity to investigate encounters where the recipient of the virus is an introduced crop and the donor a native plant and vice versa. Phylogenetic analysis of the virus coat-protein genes was used to study isolates of three potyviruses representing different ,new encounter' scenarios at this interface. The incidence, symptomatology, host range, non-persistent aphid transmission and considerable genetic diversity of the first indigenous virus described from the SWAFR, where it infects the native legume Hardenbergia comptoniana, and its potential to damage lupin, a locally important, newly introduced cultivated grain legume, was studied. The name Hardenbergia mosaic virus is proposed for this virus. Two other examples of ,new encounter' scenarios involving other legume-infecting potyviruses studied were: Passion fruit woodiness virus, which has been found only in Australasia, where it damages recently introduced species of Passiflora and legumes; and Bean yellow mosaic virus, which is not indigenous to Australia and was introduced recently to the SWAFR, where it infects a number of introduced legumes, but also damages the local native legume Kennedia prostrata. Isolates of the former had considerable genetic diversity consistent with the virus being indigenous, while isolates of the latter virus from K. prostrata had a low genetic diversity consistent with recent arrival. This research illustrates how introduced viruses can damage indigenous plants and indigenous viruses can damage introduced cultivated plants within this unique ecosystem, and how human activities can facilitate damaging ,new encounters' between plants and viruses. [source] First record of Bean yellow mosaic virus infecting a member of the orchid genus DactylorhizaPLANT PATHOLOGY, Issue 2 2007A. Skelton No abstract is available for this article. [source] A severe outbreak of melon yellow mosaic disease caused by Zucchini yellow mosaic virus in the Punjab province of PakistanPLANT PATHOLOGY, Issue 2 2006A. H. Malik No abstract is available for this article. [source] Effect of sowing date and straw mulch on virus incidence and aphid infestation in organically grown faba beans (Vicia faba)ANNALS OF APPLIED BIOLOGY, Issue 2 2009H. Saucke Abstract The effect of sowing date on aphid infestation and the incidence of aphid-transmitted viruses were investigated in organically managed, small-scale field experiments with two faba bean cultivars over 3 years (2002,04). As an additional factor, straw mulch was applied in 2 of the 3 years shortly before the start of vector activity in May. Virus incidence was determined using enzyme-linked immunosorbent assay and immunoelectron microscopy. Aphid flight activity was monitored using standard yellow water traps. Bean colonising aphids were assessed throughout the vegetation period by counting the number of plants infested with Acyrthosiphon pisum, Megoura viciae and Aphis fabae. Pea enation mosaic virus and bean yellow mosaic virus were the most abundant aphid-transmitted viruses, being detected in 22,54% and 9,69%, respectively, of the total number of virus-infected plants analysed per year. Further aphid-transmitted viruses found in faba bean were bean leaf roll virus, beet western yellows virus, clover yellow vein virus (in 2002) and soybean dwarf virus (in 2004). A. pisum was the predominant aphid species colonising faba bean plants. Early sowing compared with late sowing led to a significant reduction of the total virus incidence in faba bean in all 3 years. However, significantly decreased levels of A. pisum colonisation as a result of early sowing were observed only in 1 year and one cultivar. Irrespective of sowing date, straw mulching had no significant effects on virus incidence and aphid colonisation. Compared with late sowing, early sowing significantly increased bean yield in all 3 years and kernel weight in 2 years, whereas straw mulching had no effect on yield. [source] |