复合侵染水茄的两种菜豆金色花叶病毒属病毒基因组结构特征分析

为明确水茄Solanum torvum植株叶片邹缩、褪绿是否由菜豆金色花叶病毒属病毒侵染引起,从云南省西双版纳傣族自治州田间采集具有疑似感染症状的水茄植株叶片样品,应用菜豆金色花叶病毒属病毒简并引物和特异性引物进行PCR扩增、克隆和测序,通过生物信息软件分析比较其核苷酸序列特征,并对其进行系统发育分析。结果显示,从采集的疑似病叶中共克隆获得了5条菜豆金色花叶病毒属病毒DNA-A全序列和3条DNA-B全序列,经全序列分析发现,侵染水茄的2种菜豆金色花叶病毒属病毒分离物分别属于中国南瓜曲叶病毒(squash leaf curl China virus,SLCCNV)和野茼蒿黄脉病毒(Crassocephalum yellow vein virus,CraYVV)。SLCCNV水茄分离物的基因组具有典型的菜豆金色花叶病毒属病毒双组分结构特征,与来自泰国的SLCCNV分离物(AB330078)亲缘关系最近,相似性最高达到99.0%;CraYVV水茄分离物的基因组具有典型的菜豆金色花叶病毒属病毒单组分结构特征,与来自云南省景洪市的CraYVV分离物(EF165536)亲缘关系最近,相似性最高达到97.6%。表明水茄是这2种菜豆金色花叶病毒属病毒的新寄主,并首次发现双组分和单组分菜豆金色花叶病毒属病毒可复合侵染水茄。     

一种侵染鳢肠的双生病毒基因组特征

菜豆金色花叶病毒属病毒是热带及亚热带地区经济作物的重要病原病毒,该类病毒在田间的杂草寄主范围较为广泛。本研究从云南红河流域采集到叶脉黄化的鳢肠植株,经克隆获得了菜豆金色花叶病毒属病毒分离物YN3306,该分离物核苷酸序列全长2749 nt,具有典型的双生病毒基因组结构特征。进一步分析发现,分离物属于金腰剑曲叶病毒(Synedrella leaf curl virus,SyLCV),RDP软件分析表明,该分离物是由烟草曲茎病毒(Tobacco curly shoot virus,Tb CSV)、云南烟草曲叶病毒(Tobacco leaf curl Yunnan virus,TbLCYnV)和金腰剑曲叶病毒重组产生的病毒。本研究首次报道了GenBank中在印度注册的SyLCV可以侵染鳢肠植株。     

侵染木薯的两种单组分菜豆金色花叶病毒属病毒及卫星分子基因组结构特征分析

 为明确木薯(Manihot esculenta Crantz)植株叶片皱缩、畸形是否由菜豆金色花叶病毒属病毒侵染引起,从云南省红河州田间采集具有疑似感染症状的木薯植株叶片样品,应用菜豆金色花叶病毒属病毒简并引物、种专化性引物及卫星分子引物进行PCR扩增、克隆,通过测序分析其核苷酸序列特征并对其进行系统进化分析。结果显示,从采集疑似病叶中共克隆获得4条菜豆金色花叶病毒属病毒DNA-A全序列和6条beta卫星分子全序列,经全序列分析发现侵染木薯的2种菜豆金色花叶病毒属病毒分离物分别属于烟草曲茎病毒(tobacco curly shoot virus,TbCSV)和中国胜红蓟黄脉病毒(ageratum yellow vein China virus,AYVCNV)。TbCSV木薯分离物全基因组核苷酸序列与分离自云南的TbCSV-YN2247(KX290925)分离物亲缘关系最近,相似性最高达到96.67%;AYVCNV木薯分离物全基因组核苷酸序列与分离自云南的AYVCNV-YN4326(KU601622)分离物亲缘关系最近,相似性最高达到95.80%;侵染木薯的beta卫星分子分别为赛葵黄脉病毒beta卫星(malvastrum yellow vein betasatellite,MaYVB)和中国胜红蓟黄脉病毒beta卫星(ageratum yellow vein China virus betasatellite,AYVCNB),MaYVB-YN6332-12全基因组核苷酸序列与分离自云南的MaYVB-Y216(KX290925)分离物亲缘关系最近,相似性最高达到96.4%;AYVCNB-YN6338-17全基因组核苷酸序列与分离自海南的AYVCNB-Hn9(KU601622)分离物亲缘关系最近,相似性最高达到90.4%,表明木薯是这两种菜豆金色花叶病毒属病毒的新寄主。单组分菜豆金色花叶病毒属病毒及其伴随beta卫星分子可以复合侵染木薯植株为首次发现。     

侵染青蒿的烟草曲茎病毒的分子鉴定及基因组结构特征分析

菜豆金色花叶病毒属病毒是一类在全球热带及亚热带地区造成严重经济损失的植物病毒,田间杂草是这类病毒重要的中间寄主。 本研究从云南省玉溪市采集了表现黄脉的青蒿植株,通过PCR扩增、克隆及测序从样品中获得两条菜豆金色花叶病毒属病毒DNA-A全基因组序列,分别为YN6393-23和YN6393-27,其全长均为2 739 bp,相似性为100%。序列分析发现,YN6393-23和YN6393-27的核苷酸序列与烟草曲茎病毒Tobacco curly shoot virus(TbCSV）的分离物YN4584的核苷酸序列相似性最高,为99.45%。根据国际病毒分类委员会对菜豆金色花叶病毒属病毒种的分类标准,全基因组序列相似性大于91%则为同种病毒,表明此病毒分离物为烟草曲茎病毒的一个分离物。这是菜豆金色花叶病毒属病毒侵染青蒿植株的首次报道。     

云南凹头苋上分离到的2种菜豆金色花叶病毒属病毒基因组结构特征

菜豆金色花叶病毒属(Begomovirus)病毒是热带亚热带地区多种作物的重要病原,杂草作为该属病毒的中间寄主在病害发生流行中具有重要作用。本研究通过克隆、测序和生物信息学分析,对3株具有曲叶症状的凹头苋(Amaranthus lividus)进行菜豆金色花叶病毒属病毒的分离分析。从这些凹头苋中共分离到2种菜豆金色花叶病毒属病毒和3种beta卫星。序列分析显示,其中一种病毒与云南番茄黄化曲叶病毒相似性最高(96%),另一种与中国胜红蓟黄脉病毒相似性最高(96.5%或91%)。Beta卫星的分析显示,其中一种与云南番茄黄化曲叶beta卫星相似性最高(94.3%),另一种与赛葵曲叶beta卫星相似性最高(92%),最后一种与中国番茄曲叶beta卫星相似性最高(91%)。重组分析表明,分离物YN4331-69是一个重组病毒,是由中国胜红蓟黄脉病毒YN4326-60和一个尚未发现的菜豆金色花叶病毒属病毒重组形成。这是首次报道凹头苋被不同的菜豆金色花叶病毒属病毒及其伴随的beta卫星侵染,表明凹头苋是一个适宜该属病毒的中间寄主。     

油菜花叶病毒Wh株系的鉴定

依据病毒的寄主植物反应、血清学性质和RNA 3'末端含cp和mp基因1554 bp cDNA片段序列分析,明确一个侵染油菜的烟草花叶病毒属Tobamovirus病毒分离物是油菜花叶病毒(Oileed rape mosaic virus,ORMV)的一个株系,定名为Wh株系.ORMV-Wh侵染油菜、白菜和大白菜等十字花科的作物,初期产生典型明脉症状,对辣椒、番茄和烟草等茄科植物致病性弱;血清学与烟草花叶病毒(Tobacco mosaic virus,TMV)有明显差异.ORMV-Wh mp、cp基因和3'UTR区段大小分别为798、474和235个核苷酸,mp和cp基因有77个核苷酸重叠;与TMV序列同源性在60%以下,与侵染十字花科Tobamovirus属病毒株系序列同源性在80%以上;其中与ORMV的不同株系RMV-CAB、RMV-Sh、YoMV、YoMV-Cg和CTMV-W的同源性在90%以上.     

侵染苣荬菜的中国胜红蓟黄脉病毒及伴随的卫星基因组结构特征

杂草是菜豆金色花叶病毒属病毒的重要中间寄主,常富集多种该属病毒及其卫星病毒。2014年,在云南红河常见杂草苣荬菜Sonchus arvensis上出现了疑似菜豆金色花叶病毒属病毒病症状。利用克隆、测序和生物信息学分析技术对其所含病毒进行分离鉴定,结果从1株病样中共获得了两条菜豆金色花叶病毒属病毒全序列、两条β卫星全序列和一条α卫星全序列。序列分析显示,两条菜豆金色花叶病毒属病毒全序列与中国胜红蓟黄脉病毒相似性最高,分别为99%和96%,确定为中国胜红蓟黄脉病毒的分离物。两条β卫星全序列与赛葵黄脉β卫星相似性最高,为97%,确定为赛葵黄脉β卫星的一个分离物。α卫星全序列与中国番茄黄化曲叶α卫星相似性最高,为86.3%,是中国番茄黄化曲叶α卫星的一个分离物。这是菜豆金色花叶病毒属病毒病害复合体在中国侵染苣荬菜的首次报道。     

TaqMan探针法实时荧光定量RT-PCR检测番茄斑驳花叶病毒

番茄斑驳花叶病毒（tomato mottle mosaic virus,ToMMV）为近年来发现的一种烟草花叶病毒属新成员,是茄科作物上危害严重的主要病毒之一,近几年EPPO全球数据库报道多个国家从进境辣椒和番茄种子中截获该病毒。为防止番茄斑驳花叶病毒通过种子种苗进行传播扩散,本文根据该病毒GenBank中不同分离株外壳蛋白（coat protein,CP）基因保守序列设计特异性引物和探针,建立了TaqMan探针法实时荧光定量RT-PCR检测ToMMV的方法。结果表明,本检测方法特异性强,对烟草花叶病毒（tobacco mosaic virus,TMV）、番茄花叶病毒（tomato mosaic virus,ToMV）、番茄褐色皱果病毒（tomato brown rugose fruit virus,ToBRFV）、黄瓜绿斑驳花叶病毒（cucumber green mottle mosaic virus,CGMMV）、辣椒轻斑驳病毒（pepper mild mottle virus,PMMoV）、番茄环斑病毒（tomato ringspot virus,TomRSV）6种病毒均无交叉反...     

马来西亚某些蔬菜作物病毒病的发生情况

马来西亚辣椒、甜椒、番茄、茄子、菠菜和黄瓜病毒病发生情况调查表明:80%以上的辣椒感染花叶病,并导致辣椒减产。鉴定了9个辣椒病株标样,其中3个标样由辣椒脉斑驳病毒(Chilli veinal mottle virus,CVMV)单独侵染,其余为两种病毒复合侵染,CVMV 和黄瓜花叶病毒普通株系(CMV—O)、CVMV 和烟草花叶病毒番茄株系(TMV-t)、CVMV 和 CMV 的辣椒株系(CMV-C)复合侵染分别占标样数的2,2,1,1。甜椒病毒病的发生率低于辣椒(由于绝大部分甜椒在塑料大棚栽培的缘故),鉴定     

巴西中部大豆上发生的一种菜豆皱缩花叶病毒株系

1989年,在巴西中部EMBRAPA和CPAC地区的田中从表现斑驳的大豆上分离到一种病毒,根据寄主范围、症状、传播方式、病毒粒子形态和血清学研究判断,该种病毒鉴定为菜豆皴缩花叶病毒的一个株系,属于豌豆花叶病毒组。     

Species diversity,phylogeny and genetic variability of begomovirus populations infecting leguminous weeds in northeastern Brazil

A survey of begomoviruses infecting leguminous weeds (family Fabaceae) was carried out in four states of northeastern Brazil. A total of 26 full‐length begomovirus components (19 DNA‐A and seven DNA‐B, with three pairs of cognate A and B components) were amplified using rolling‐circle amplification, then cloned and sequenced. Sequence analysis indicated the presence of six species, four of them novel. In phylogenetic analysis five of the viruses clustered with other Brazilian begomoviruses, but one of them (Euphorbia yellow mosaic virus, EuYMV) clustered with viruses from other countries in Central and South America. Evidence of recombination was found among isolates of Macroptilium yellow spot virus (MaYSV). The MaYSV population had a high degree of genetic variability. Macroptilium lathyroides was revealed as a common host for several of these viruses, and could act as a mixing vessel from which recombinant viruses could emerge. The results indicate that leguminous weeds are reservoirs of several begomoviruses in Brazil, and could play a significant role in begomovirus epidemics, both as inoculum sources and as sources of emerging novel viruses.     

侵染假酸浆的泰国番茄黄化曲叶病毒全基因组结构特征

为明确假酸浆Nicandra physalodes叶片黄化、皱缩症状是否由菜豆金色花叶病毒属病毒侵染引起,本研究利用分子检测方法和生物信息学技术鉴定了假酸浆样品中的病毒种类。从采集的病样中克隆并获得了2条菜豆金色花叶病毒属病毒DNA-A全序列和1条beta卫星全序列,经全序列分析发现,该双生病毒的两条DNA-A全序列与泰国番茄黄化曲叶病毒(tomato yellow leaf curl Thailand virus, TYLCTHV)云南分离物TYLCTHV-YN1732一致性最高,达99.3%,亲缘关系较近;beta卫星的全序列与云南番茄曲叶beta卫星(tomato leaf curl Yunnan betasatellite, TLCYnB)的分离物YN5230一致性最高,达99.3%,亲缘关系较近。重组分析显示,假酸浆上分离的TYLCTHV-YN5735-12是一个重组病毒,有两个重组事件,一个主要发生在AV1的编码区,由中国番茄黄化曲叶病毒(tomato yellow leaf curl China virus, TYLCCNV)和广西大戟曲叶病毒(euphorbia lea...     

Tomato leaf curl Guangxi virus is a distinct monopartite begomovirus species

Three begomovirus isolates were obtained from tomato plants showing leaf curl symptoms in Guangxi province of China. Typical begomovirus DNA components representing the three isolates (GX-1, GX-2 and GX-3) were cloned and their full-length sequences were determined to be 2752 nucleotides. Nucleotide identities among the three viral sequences were 98.9–99.7%, but all shared <86.7% nucleotide sequence identity with other reported begomoviruses. The sequence data indicated that GX-1, GX-2 and GX-3 are isolates of a distinct begomovirus species for which the name Tomato leaf curl Guangxi virus (ToLCGXV) is proposed. Further analysis indicated that ToLCGXV probably originated through recombination among viruses related to Ageratum yellow vein virus, Tomato leaf curl China virus and Euphorbia leaf curl virus. PCR and Southern blot analyses demonstrated that isolates GX-1 and GX-2 were associated with DNAβ components, but not isolate GX-3. Sequence comparisons revealed that GX-1 and GX-2 DNAβ components shared the highest sequence identity (86.2%) with that of Tomato yellow leaf curl China virus (TYLCCNV). An infectious construct of ToLCGXV isolate GX-1 (ToLCGXV-GX) was produced and determined to be highly infectious in Nicotiana benthamiana, N. glutinosa, tobacco cvs. Samsun and Xanthi, tomato and Petunia hybrida plants inducing leaf curl and stunting symptoms. Co-inoculation of tomato plants with ToLCGXV-GX and TYLCCNV DNAβ resulted in disease symptoms similar to that caused by ToLCGXV-GX alone or that observed in infected field tomato plants.     

云南烟草产区辣椒脉斑驳病毒的调查及其遗传多样性分析

明确辣椒脉斑驳病毒(chilli veinal mottle virus, ChiVMV)在云南6个州(市)烟草生产区的分布、遗传多样性和群体遗传结构,对病害的防控预警具有重要意义。本研究以2022年采集自云南6个州(市)不同烟草产区的96份疑似感染ChiVMV的烟草样品为试验材料,利用电子显微镜负染色观察和分子生物学方法对病毒进行检测和鉴定,获得21个ChiVMV云南烟草分离物的cp基因序列。利用SDT、MEGA、RDP、DnaSP及Arlequin等生物学软件对21个云南烟草分离物及NCBI上下载的38个来自不同国家、地区及寄主的ChiVMV分离物cp基因序列的系统进化、遗传多样性和群体遗传结构特征进行分析。结果显示,从云南6个州(市)烟草生产区采集的96份烟草样品中,ChiVMV检出率为51.04%;序列比对发现,本研究获得的cp基因与NCBI中38个ChiVMV分离物cp基因的核苷酸一致性在84.1%以上;系统发育分析发现,59个ChiVMV分离物按照地理位置的远近被划分为4个分支,聚类结果具有明显的地理分布特征,而与寄主植物无关;遗传多样性和遗传分化分析表明,4个地理种群的ChiVMV cp基因遗传多样性水平均较高,中国种群与印度、泰国和其他国家种群间发生了很大的遗传分化且差异显著(P<0.05);遗传力分析显示,基因交流、遗传漂变和基因的负选择压力是ChiVMV分离物适应性进化的重要方式。     

Agroinoculation Shows Tobacco leaf curl Yunnan virus is a Monopartite Begomovirus

We demonstrated that only 2 out of 15 isolates of Tobacco leaf curl Yunnan virus (TbLCYNV) were associated with the satellite DNAβ molecules. To investigate the infectivity of this virus, an infectious clone of TbLCYNV isolate Y143 (TbLCYNV-Y143) was agroinoculated or whitefly transmitted into Nicotiana benthamiana, N. glutinasa, Petunia hybrida and N. tabacum. TbLCYNV-Y143 alone was able to induce severe upward leaf curling, vein thickening or stunt symptoms in these plants. Co-inoculation of TbLCYNV-Y143 with DNAβ molecules associated with other begomoviruses induced similar symptom types on these plants. This indicates that TbLCYNV is a monopartite begomovirus. The relevance of results that only two isolates of TbLCYNV were associated with DNAβ molecules is discussed.     

Virus transmission by host-specific strains ofOlpidium bornovanus andOlpidium brassicae

Zoospores of 12 isolatesO. bornovanus from geographically diverse sites and representing the three host specific cucurbit strains were tested as vectors for seven viruses using watermelon bait plants and the in vitro acquisition method. All isolates of the cucumber, melon, and squash strains transmitted melon necrotic spot carmovirus (MNSV) and cucumber necrosis tombusvirus (CNV) but none transmitted petunia asteroid mosaic tombusvirus (PAMV) or tobacco necrosis necrovirus (TNV). The isolates varied as vectors of three other carmoviruses: cucumber leaf spot virus (CLSV); cucumber soil borne virus (CSBV); and squash necrosis virus (SqNV). All cucumber isolates transmitted CLSV and SqNV but not CSBV. Some of the melon isolates transmitted CLSV and SqNV but none transmitted CSBV. Two squash isolates transmitted CSBV and SqNV but not CLSV. Two isolates ofO. brassicae transmitted only TNV and a third did not transmit any of the viruses. The species of bait plant sometimes affected transmission. The most efficient vector strains ofO. bornovanus, as determined by reducing zoospores and virus in the inoculum, were the cucumber strain for CLSV; the cucumber strain for CNV if cucumber was the bait plant or melon strain if watermelon was the bait plant; and the squash strain for SqNV. The plurivorous strain ofO. brassicae was the most efficient vector of TNV.Olpidium bornovanus is the first vector reported for CSBV and is confirmed as a vector of SqNV. It is proposed that all carmoviruses may have fungal vectors.Ligniera sp. did not transmit any of the viruses in one attempt.Abbreviations CLSV cucumber leaf spot virus - CNV cucumber necrosis virus - CSBV cucumber soil borne virus - MNSV melon necrotic spot virus - PAMV petunia asteroid mosaic virus - SqNV squash necrosis virus - TNV tobacco necrosis virus - TBSV tomato bushy stunt virus     

Analysis of coat protein gene sequences of begomoviruses associated with different weed species in India

Sida cordifolia L., Croton bonplandianum L., Malachra capitata L., Eclipta prostrata L., Clerodendron inerme L., Acalypha indica L., and Urena lobata L. are common weeds found all over India. They are often infected by different begomovirus complexes and may act as reservoirs of crop-infecting begomoviruses. Cloning and sequencing were done to partially characterize the begomovirus complexes associated with these weed species from the eastern part of India and their genetic pattern was compared with respective geographical isolates throughout India. Coat protein (CP) genes were found to be amplified from all the infected samples tested in this study, whereas betasatellite molecules amplified only from four infected samples (Sida, Croton, Malachra and Urena). Sequence analysis using CP genes and betasatellites of the present begomovirus complexes showed significant variation among their geographical isolates and also exhibited closeness to different crop-infecting begomovirus complexes. The majority of the weed-infecting begomovirus complexes characterized in this paper are reported for the first time from India.