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1.
S.K. Raj R. Singh S.K. Pandey B.P. Singh 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(5):467-470
Natural occurrence of a geminivirus causing severe leaf curl disease on sunn hemp (Crotalaria juncea) was recorded in India. The association of a geminivirus with the disease was demonstrated by whitefly transmission tests and polymerase chain reaction (PCR) amplification of DNA fragments of expected sizes with three pairs of degenerate geminivirus primers. The PCR-amplified viral DNA fragments were further characterized by Southern hybridization with a geminivirus probe consisting of the cloned coat protein (CP) gene of Indian tomato leaf curl virus (ITLCV). Restriction fragment length polymorphism analysis of a PCR-amplified CP fragment revealed that the geminivirus from sunn hemp was different than ITLCV. 相似文献
2.
Plant Viruses Transmitted by Whiteflies 总被引:18,自引:0,他引:18
David R. Jones 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(3):195-219
One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text. 相似文献
3.
从海南省杂草胜红蓟和假马鞭上检测到粉虱传双生病毒 总被引:9,自引:0,他引:9
利用三抗体夹心ELISA(TAS-ELISA)及PCR检测的方法对采自海南的胜红蓟(Ageratum conyzoides)和假马鞭(Stachytarphetajamaicensis)的5个病样进行了检测,表明均为粉虱传双生病毒。PCR扩增产物克隆后进行序列测定,结果表明存在2类双生病毒,其中样品Hn2存在2类病毒的复合侵染。这是在海南首次报道存在有粉虱传双生病毒。 相似文献
4.
双生病毒是一类在全球范围内危害严重的单链环状DNA病毒。本研究从2017年采自云南的胜红蓟样品中(YN2017)获得了一条菜豆金色花叶病毒属病毒和一条β卫星的全基因组序列。该双生病毒的全长序列与烟草曲茎病毒的相似性最高,为99.60%,确定为烟草曲茎病毒的分离物。YN2017β卫星与中国胜红蓟黄脉β卫星的同源性最高,为90.8%。进一步分析发现,该β卫星的卫星保守区域(SCR)至富含腺嘌呤区(A-rich区)之间约1 kb的序列与中国胜红蓟黄脉β卫星相应序列的相似性高达97.2%;其包含的A-rich区上游与SCR之间约300 bp的序列与中国胜红蓟黄脉β卫星相应序列的相似性仅为70.2%,而与烟草曲茎β卫星相应序列的相似性最高,为97.3%。重组分析发现,所分离的β卫星是由中国胜红蓟黄脉β卫星和烟草曲茎β卫星重组产生。这是首次在中国发现由不同的β卫星重组产生的β卫星分子。 相似文献
5.
Genetic diversity and mixed infections of begomoviruses infecting tomato, pepper and cucurbit crops in Nicaragua 总被引:1,自引:0,他引:1
M. Ala-Poikela E. Svensson ‡ A. Rojas T. Horko L. Paulin J. P. T. Valkonen A. Kvarnheden † 《Plant pathology》2005,54(4):448-459
Begomoviruses were detected in Nicaraguan fields of tomato ( Lycopersicon esculentum ) and adjacently growing plants of pepper ( Capsicum annuum ), chilli pepper ( C . baccatum ), cushaw ( Cucurbita argyrosperma ) and Mexican fireplant ( Euphorbia heterophylla ) using polymerase chain reaction (PCR) and universal begomovirus primers. All tomato and Mexican fireplant plants showing symptoms were infected with begomoviruses, while only 30–46% of the pepper, chilli pepper and cushaw plants showing symptoms tested virus-positive. No begomoviruses were found in potato. The virus species were provisionally identified by sequencing 533 bp of the viral coat protein gene ( AV1 ). Tomato severe leaf curl virus (ToSLCV), Tomato leaf curl Sinaloa virus (ToLCSinV) and Pepper golden mosaic virus (PepGMV) were found to infect both tomato and pepper. A new provisional species designated Tomato leaf curl Las Playitas virus (ToLCLPV) was detected in a tomato plant. Squash yellow mottle virus (SYMoV) and PepGMV were found in cucurbits, the latter for the first time in this host. Euphorbia mosaic virus (EuMV) was detected in Mexican fireplant. Sequencing of a larger number of PCR-amplified clones from selected plants revealed intraspecific viral sequence variability, and also multiple begomovirus infections which could represent up to three species in a single tomato or cushaw plant. Phylogenetic grouping of virus sequences did not correlate with the host of origin. 相似文献
6.
The virological situation of cassava in Africa is increasing in complexity due to the number and types of viruses isolated
from different locations within the continent. Here, we report the complete nucleotide sequences of both A and B components
of two geminivirus species infecting cassava in the Ivory Coast and review the current knowledge of the molecular and biological
diversity of the African cassava geminiviruses. As a whole, newly obtained sequences are compared with those of the African
cassava mosaic geminiviruses identified to date. Results indicate that all isolates of African cassava mosaic virus (ACMV), irrespective of their geographical origin are clustered together with little or no variation in their genomic sequence.
On the contrary, the genomes of the East African cassava mosaic virus (EACMV) are more genetically diverse due to the frequent occurrence of recombinations within their two components. Indeed,
the EACMV-like viruses vary so much that their classification is becoming problematic. In addition, there is also a large
range of phenotypic symptom variation for each of these virus species, irrespective of the location of isolation. Furthermore,
it has been shown that ACMV and EACMV can be synergistic in cassava, resulting in a greater DNA accumulation and consequently
inducing severe symptoms. For all these reasons, this paper initiates a discussion concerning the species demarcation for
cassava geminivirus.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Sergio Hernández-Verdugo Ramón G. Guevara-González Rafael F. Rivera-Bustamante Ken Oyama 《Euphytica》2001,122(1):31-36
Plants collected in thirteen wild populations of Capsicum annuum from Northwest Mexico were tested for resistance to the pepper huasteco begomovirus (formerly subgroup III) (PHV) that is
transmitted by the white fly Bemisia tabaci Genadius. Plants were inoculated using both grafting and biolistic methods. Presence of viral DNA was detected by dot blot
hybridization and densitometry. Populations varied in their resistance to PHV. Plants of only two of the populations either
did not develop disease symptoms or showed very light symptoms after inoculation. In some cases, symptoms appeared several
days after inoculation. In plants of these populations viral DNA was detected by dot-blot hybridization assays but they appear
to be a good source of resistance (symptomless) for use in breeding programmes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
Genomic characterization using nonradioactive probes, polymerase chain reaction with degenerate primers for whitefly transmitted geminiviruses and nucleotide sequencing were used to describe a new bipartite geminivirus, associated with dwarfing and leaf curling of tomatoes and peppers in Jamaica. Partial DNA-A and DNA-B clones were obtained. DNA sequence analysis showed that tomato and pepper samples have a similar geminivirus associated with them. Nucleotide sequence identity > 92% between the common regions of DNA-A and DNA-B confirmed the bipartite nature of the Jamaican geminivirus isolates. Nucleotide sequence comparisons of DNA-A and DNA-B with those of geminiviruses representing the major phylogenetic groups of Western Hemisphere geminiviruses showed the greatest similarity to potato yellow mosaic virus and members of the Abutilon mosaic virus cluster of geminiviruses. This new virus is given the name tomato dwarf leaf curl virus (TDLCV) because of the dwarfing and leaf curling symptoms associated with infected tomato plants. Polymerase chain reaction and Southern hybridization showed mixed infections of TDLCV with tomato yellow leaf curl virus from Israel in 16% of the field samples of tomatoes and peppers. 相似文献
9.
Evidence for two predominant viral lineages,recombination and subpopulation structure in begomoviruses associated with yellow vein mosaic disease of okra in India 下载免费PDF全文
V. Venkataravanappa H. C. Prasanna C. N. Lakshminarayana Reddy M. Krishna Reddy 《Plant pathology》2015,64(3):508-518
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.
Genomic Analysis of the Natural Population of Wheat dwarf virus inWheat fromChina and Hungary 下载免费PDF全文
LIU Yan WANG Biao Gyula Vida Mónika Cséplo-Károlyi WU Bei-lei WU Yuan-hua WANG Xifeng 《农业科学学报》2012,12(12):2020-2027
During the last decade, the leafhopper transmitted Wheat dwarf virus (WDV) has become a serious problem both in northwestern China and Hungary. In order to study the molecular diversity and population structure of WDV in these two countries, 39 Chinese isolates and 16 Hungarian isolates were collected from different regions of China and Hungary, and their genomes were sequenced. All isolates belonged to the wheat strain of WDV and showed limited genetic diversity. The highest and lowest nucleotide sequence identities among isolates from China and Hungary were 99.9 and 90%, respectively. In all isolates, the lowest nucleotide sequence identity was 89.5% between MO10-1 and KP10-5, which were collected from Martonvásár and Kompolt, Hungary. Phylogenetic analyses showed the genome sequences of 55 WDV isolates belong to two big clades, but no clear correlation to geographical location. Population difference analyses indicated that the Chinese and Hungarian WDV populations have no significant difference. The regions in WDV genome with relatively low nucleotide diversities represented protein coding regions suggested that these regions evolved under negative selection, and might be one of the causes restricting the number of genetic variants. 相似文献