First report of a complete genome sequence for a begomovirus infecting Jatropha gossypifolia in the Americas

Jatropha gossypifolia is a weed that is commonly found with yellow mosaic symptoms growing along the roadside and in close proximity to cultivated crops in many farming communities in Jamaica. For the first time, the complete genome sequence of a new begomovirus, designated jatropha mosaic virus-[Jamaica:Spanish Town:2004] (JMV-[JM:ST:04]), was determined from field-infected J. gossypifolia in the western hemisphere. DNA-A nucleotide sequence comparisons showed closest identity (84 %) to two tobacco-infecting viruses from Cuba, tobacco mottle leaf curl virus-[Cuba:Sancti Spiritus:03] (TbMoLCV-[CU:SS:03]) and tobacco leaf curl Cuba virus-[Cuba:Taguasco:2005] (TbLCuCUV-[CU:Tag:05]), and two weed-infecting viruses from Cuba and Jamaica, Rhynchosia rugose golden mosaic virus-[Cuba:Camaguey:171:2009] (RhRGMV- [CU:Cam:171:09]) and Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). Phylogenetic analysis revealed that JMV-[JM:ST:04] is most closely related to tobacco and tomato viruses from Cuba and WGMSTV-[JM:Alb:05], a common malvaceous-weed-infecting virus from eastern Jamaica, and that it is distinct from begomoviruses infecting Jatropha species in India and Nigeria.     

The molecular characterisation of a Sida-infecting begomovirus from Jamaica

The complete DNA sequence of both genome components of a new begomovirus (Sida golden mosaic Buckup virus-[Jamaica:St. Elizabeth:2004]; SiGMBuV-[JM:SE:04]) was determined from a field-infected Sida sp. sample from Buckup, St. Elizabeth, Jamaica. Phylogenetically, both genome components of SiGMBuV-[JM:SE:04] are most closely related to malvaceous weed-infecting Floridian and Mexican begomoviruses. Its DNA-B is a recombinant molecule, the majority of which was derived from a virus resembling Sida yellow mosaic Yucatan virus-[Mexico:Yucatan:2005] (SiYMYuV-[MX:Yuc:05]), while nucleotides 43-342 were derived from a virus resembling Sida golden mosaic virus-[United States of America:Florida] (SiGMV-[US:Flo]). Symptomatic infectivity of our cloned SiGMBuV-[JM:SE:04] components was confirmed in Nicotiana benthamiana.     

Molecular characterization of a distinct bipartite begomovirus species infecting tomato in India

A distinct bipartite begomovirus was found associated with tomato plants showing yellowing, curling, and crumpling of the leaves, in a sub-temperate region in India. The complete DNA-A and DNA-B components were amplified through rolling circle amplification (RCA) using Φ-29 DNA polymerase and characterized. The DNA-A of the isolate was comprised of 2,756 nucleotides, encoding six open reading frames (ORFs) and DNA-B that of 2,725 nucleotides, encoding two ORFs. Genome organization of the isolate was typical of an old world bipartite begomovirus. Comparisons showed that DNA-A and its intergenic region (IR) have the highest sequence identity (86% and 84%, respectively) with the Tomato leaf curl New Delhi virus (ToLCNDV; DQ116885) and some other begomoviruses (>84%) reported from cucurbits and tomato. This data suggested that the isolate is a distinct begomovirus species for which a name Tomato leaf curl Palampur virus (ToLCPMV) is proposed. DNA-B showed the maximum sequence identity (73%) with Tomato leaf curl New Delhi virus-India-[Pakistan:Dargai:T5/6:2001] (AY150305). The common region (CR) of DNA-A and DNA-B showed 94% sequence similarity with each other. In the present study, phylogenetic relationship of this new species was also established with different begomoviruses reported from tomato and other begomoviruses showing highest homologies with complete DNA-A and DNA-B sequences. ToLCPMV is being reported from a sub-temperate region in India which was previously unaffected by begomoviruses and its whitefly vector. An erratum to this article can be found at     

Molecular characterization and phylogeny of two begomoviruses infecting <Emphasis Type="Italic">Malvastrum americanum</Emphasis> in Jamaica: evidence of the contribution of inter-species recombination to the evolution of malvaceous weed-associated begomoviruses from the Northern Caribbean

Two distinct full-length begomovirus DNA-A components and a DNA-B component were PCR amplified, cloned and sequenced from Jamaican Malvastrum americanum plants exhibiting yellow mosaic symptoms. Whereas one of the DNA-A components is from a potentially new species that we have tentatively named Malvastrum yellow mosaic Helshire virus (MaYMHV), the other DNA-A and the DNA-B form a cognate pair and represent a new virus species tentatively named Malvastrum yellow mosaic Jamaica virus (MaYMJV). The MaYMJV genome components together infected M. americanum and produced yellow mosaic symptoms similar to those seen in naturally infected plants. Both the MaYMJV and MaYMHV DNA-A components are typical of those of bipartite begomoviruses from the Western Hemisphere. The DNA-As of MaYMJV and MaYMHV are most closely related to each other (sharing 84% sequence identity) and cluster phylogenetically with begomoviruses found infecting malvaceous weeds in Cuba and Florida. The DNA-B component of MaYMJV is most similar to that of Sida golden mosaic virus-[USA:Florida] (SiGMV-[US:Flo]) and Sida golden mosaic Costa Rica virus-[Costa Rica] (SiGMCRV-[CR]). As with many other geminivirus species, the genomes of MaYMJV and MaYMHV bear traces of inter-species recombination.     

A novel recombinant tomato-infecting begomovirus capable of transcomplementing heterologous DNA-B components

The genome of a tomato-infecting begomovirus from Ranchi, India, was cloned, sequenced and analysed. The viral genome shared 88.3% sequence identity with an isolate belonging to the species Tobacco curly shoot virus (TbCSV), and this virus should therefore be considered a member of a new species, tentatively named Tomato leaf curl Ranchi virus (ToLCRnV). The DNA-?? molecule, which had 74.5% sequence identity with tomato leaf curl Bangladesh betasatellite (ToLCBDB), is named tomato leaf curl Ranchi betasatellite (ToLCRnB). Phylogenetic analysis revealed that ToLCRnV is related to tomato leaf curl Bangladesh virus (ToLCBDV), tobacco curly shoot virus (TbCSV) and tomato leaf curl Gujarat virus (ToLCGV). An infectivity study with ToLCRnV established the monopartite nature of the viral genome, whereas inoculation with ToLCRnB resulted in increased symptom severity. ToLCRnV could transreplicate DNA-B of tomato leaf curl Gujarat virus (ToLCGV) and tomato leaf curl New Delhi virus (ToLCNDV), both in N. benthamiana and tomato, although DNA-B accumulation of was less than with the wild-type combinations. ToLCRnB could be efficiently replicated by DNA-A of both ToLCNDV and ToLCGV. A leaf disk assay suggests that DNA-A could transreplicate the homologous DNA-B and DNA-?? more efficiently than the heterologous one.     

Characterization and distribution of tomato yellow margin leaf curl virus, a begomovirus from Venezuela

A begomovirus causing mottling and leaf deformation in tomato from the State of Mérida was cloned and sequenced. The virus has a bipartite genome comprised of a DNA-A (2,572 nucleotides) and a DNA-B (2,543 nucleotides) with a genome organization typical of New World begomoviruses. Both components share a common region of 115 nucleotides with 98 % sequence identity. Phylogenetic analysis indicated that while no virus sequences were closely related, the A component was distantly related to those of two other tomato-infecting viruses, tomato leaf deformation virus and Merremia mosaic virus; and the DNA-B, to those of pepper huasteco yellow vein virus and Rhynchosia golden mosaic Yucatan virus. The DNA-A and DNA-B sequences were submitted to GenBank (accession no. AY508993 and AY508994, respectively) and later accepted by the International Committee on Taxonomy of Viruses as the genome of a member of a unique virus species with the name Tomato yellow margin leaf curl virus (TYMLCV). Tomato (Solanum lycopersicum L. ‘Fl. Lanai’) plants inoculated with cloned TYMLCV DNA-A and DNA-B became systemically infected and showed chlorotic margins and leaf curling. The distribution of TYMLCV in tomato-producing states in Venezuela was determined by nucleic acid spot hybridization analysis of 334 tomato leaf samples collected from ten states using a TYMLCV-specific probe and confirmed by PCR and sequencing of the PCR fragment. TYMLCV was detected in samples from the states of Aragua, Guárico, and Mérida, suggesting that TYMLCV is widely distributed in Venezuela.     

Complete nucleotide sequence of <Emphasis Type="Italic">Croton yellow vein mosaic virus</Emphasis> and DNA-β associated with yellow vein mosaic disease of <Emphasis Type="Italic">Jatropha gossypifolia</Emphasis> in India

A severe yellow vein mosaic disease was noticed on several Jatropha gossypifolia plants growing nearby agriculture fields at Lucknow, India. Diseased plants exhibited yellow vein mosaic, leaf deformation, vein swelling and stunting. A population of whiteflies (Bemisia tabaci) was also noticed in the vicinities; therefore, begomovirus infection was suspected. To confirm begomovirus association, total DNA was isolated from symptomatic leaf samples and subjected to PCR using DNA-A, DNA-B and DNA-β-specific primers. DNA-A and DNA-β was successfully amplified but several attempts failed to amplify DNA-B indicating monopartite nature of the begomovirus. The sequence analysis of amplicons revealed the presence of 2757 nucleotides of DNA-A genome (EU727086) and 1315 nt of DNA-β molecule (EU604296). The sequence analysis of DNA-A (EU727086) revealed the highest 96% identities and closest relationship with Croton yellow vein mosaic virus (CYVMV, AJ507777) infecting Croton bonplandianum in India. The DNA-β (EU604296) showed the highest 96% sequence identity and closest phylogenetic relationship with CYVMV-associated DNA-β (AM410551) isolated from Croton sp. in Pakistan. Based on the highest sequence identities and closest phylogenetic relationships of the DNA-A genome and DNA-β molecule with respective sequences of various isolates of Croton yellow vein mosaic virus, the begomovirus associated with yellow vein mosaic disease of J. gossypifolia was identified as an isolate of Croton yellow vein mosaic virus.     

Sequence characterization of Tomato leaf curl Sinaloa virus and <Emphasis Type="Italic">Tomato severe leaf curl virus</Emphasis>: Phylogeny of New World begomoviruses and detection of recombination

Summary. Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious constraint to tomato production in Nicaragua. In this study, the complete nucleotide (nt) sequences of the DNA-A and DNA-B components were determined for the first time for Tomato leaf curl Sinaloa virus (ToLCSinV). In addition, the complete nt sequence was determined for the DNA-A component of two isolates of Tomato severe leaf curl virus (ToSLCV). The genome organization of ToLCSinV and ToSLCV was identical to the bipartite genomes of other begomoviruses described from the Americas. A phylogenetic analysis of DNA-A including 45 begomovirus species showed that the indigenous begomoviruses of the New World can be divided into three major clades and an intermediate group: AbMV clade, SLCV clade, “Brazil clade”, and BGYMV group. Phylogenetic analyses of the DNA-A and DNA-B components and their open reading frames indicated that ToLCSinV and ToSLCV belong to different clades: ToLCSinV to the AbMV clade, and ToSLCV to the SLCV clade. The two Nicaraguan isolates of ToSLCV showed a close relationship with ToSLCV from Guatemala (ToSLCV-[GT96-1]) and Tomato chino La Paz virus (ToChLPV), but differed significantly in the AV1 and AC1 regions, respectively. Computer-based predictions indicated that recombination with another begomovirus had taken place within AV1 of ToSLCV dividing this species into two strains. A high probability was also found that ToChLPV is involved in the evolution of ToSLCV.     

Characterization of Rhynchosia yellow mosaic Yucatan virus, a new recombinant begomovirus associated with two fabaceous weeds in Yucatan, Mexico

Rhynchosia minima (L.) DC. (Fabaceae) plants exhibiting bright golden mosaic symptoms were previously associated with begomovirus infection in Yucatan, México [1]. To characterize the begomovirus infecting these plants, the complete bipartite genome was cloned and sequenced. Sequence comparisons indicated that the virus was distinct from all other begomoviruses known to date, including those previously identified from symptomatic R. minima, and the name Rhynchosia yellow mosaic Yucatan virus (RhYMYuV) is proposed. Pairwise comparisons indicated that RhYMYuV DNA-A [2,597 nt, (EU021216)] and DNA-B [2,542 nt, (FJ792608)] components shared the highest nt sequence identity with Cabbage leaf curl virus (CaLCuV), 87% for component A and 71% for component B. Phylogenetic analysis indicated that both components of RhYMYuV are most closely related to other New World begomoviruses, having as closest relatives immediate outliers to the major Squash leaf curl virus (SLCV) clade. Recombination analysis of the RhYMYuV genome indicated that the DNA-A component has arisen through intermolecular recombination. R. minima plants inoculated with the monomeric clones developed a bright yellow mosaic similar to symptoms observed in naturally infected plants, confirming that the clones were infectious. Nicotiana benthamiana plants biolistically inoculated with monomeric clones developed curling and chlorosis in the newly emerging leaves. RhYMYuV was also detected in symptomatic Desmodium sect. Scorpiurus Benth. (Fabaceae) that were collected near the RhYMYuV-infected plants.     

Identification and molecular characterization of begomovirus and associated satellite DNA molecules infecting <Emphasis Type="Italic">Cyamopsis tetragonoloba</Emphasis>

Monopartite begomoviruses comprise DNA-A as the main genome and associated satellite DNAs. Viral DNA extracted from guar (Cyamopsis tetragonoloba) showing leaf curl symptoms exhibited positive amplification of coat protein (CP) gene of DNA-A component, suggesting the presence of begomovirus. Full length DNA-A was amplified by primer pair re-designed from CP gene nucleotide sequence. The associated alphasatellite and betasatellite DNA molecules were amplified and sequenced, confirming the presence of monopartite begomovirus. Sequence comparisons showed 89% identity with other begomoviruses. The Neighbor-Joining tree based on full length DNA-A nucleotide sequence showed that the guar infecting begomovirus clustered separately from other known begomoviruses. The betasatellite shared a high (96%) nucleotide identity to Cotton leaf curl Multan betasatellites. The alphasatellite showed 91% nucleotide identity to alphasatellite associated with begomovirus infecting Okra. Recombination analyses showed three recombinant fragments in DNA-A, two in betasatellite, and four in alphasatellite. The results suggest that the begomovirus identified in this study was a new recombinant virus. Its name was proposed as Cyamopsis tetragonoloba leaf curl virus (CyTLCuV).     

Biological and molecular characterization of a begomovirus associated with yellow mosaic vein mosaic disease of pumpkin from Northern India

The biological and molecular properties of Squash leaf curl China virus from Varanasi, India (SLCCNV-IN[IN:Var:Pum]) were characterized. SLCCNV-IN[IN:Var:Pum] could be transmitted by grafting and through whitefly transmission. The complete DNA-A and DNA-B components were amplified through PCR using specific DNA-A and DNA-B primers. The DNA-A of the isolate was comprised of 2,738 nucleotides, encoding typical six open reading frames, and DNA-B of 2,704 nucleotides, encoding two ORFs. Genome organization of the isolate was typical of an old world bipartite begomovirus. Comparisons showed that DNA-A and its intergenic region have the highest sequence identity (97.6 and 97.4%, respectively) with the SLCCNV-IN[IN:Luc:Pum]; (DQ026296). This data suggested that the isolate is a same begomovirus species for which the name Squash leaf curl China virus-India[India:Varanasi:Pumpkin] is proposed. DNA-B showed maximum sequence identity (89.2%) with SLCCNV-IN[IN:Coi:Pum] (AY184488). Phylogenetic analysis of the present isolate showed close relationship to other cucurbit-infecting geminiviruses. This is the first evidence of occurrence of the bipartite Squash leaf curl China virus associated with severe yellow mosaic disease of pumpkin in northern India.     

Isolation and molecular characterization of a distinct begomovirus and its associated betasatellite infecting Hedyotis uncinella (Hook. et Arn.) in Vietnam

A begomovirus isolate VN1 associated with symptomatic Hedyotis uncinella Hook. et Arn. from Vietnam was characterized. The virus, which we provisionally name H. uncinella yellow mosaic virus (HUYMV), has a monopartite genome of 2,749 nucleotides (nts). Pairwise comparisons of DNA-A sequences showed that HUYMV had a maximum nt sequence identity with Soybean crinkle leaf virus (SbLCV) and Premna leaf curl virus (PLCuV) at 82.1 and 81.9 %, respectively, which are less than the 89 % identity in the complete genome, which has been used as the threshold value for demarcation of species in the genus Begomovirus, the family Geminiviridae. One recombination event was detected for HUYMV, which involves an unknown begomovirus as the major parent and Tomato leaf curl Philippines virus (ToLCPV) as the minor parent, with nt 2163 and nt 2452 as the beginning and ending breakpoints, respectively. A betasatellite was found to be associated with HUYMV. The betasatellite showed the highest nt sequence identity (70 %) with Tomato leaf curl Philippine betasatellite—[Philippines:Laguna2:2006]. The name H. uncinella yellow mosaic betasatellite [Vietnam: Binh Dinh: 2013] was proposed for the betasatellite.     

Tomato chlorotic leaf distortion virus,a new bipartite begomovirus infecting <Emphasis Type="Italic">Solanum lycopersicum</Emphasis> and <Emphasis Type="Italic">Capsicum chinense</Emphasis> in Venezuela

Virus isolate T217L was obtained from a diseased tomato (Solanum lycopersicum) plant showing leaf deformation and chlorotic mottle symptoms near Maracaibo in the state of Zulia, Venezuela. Full-length DNA-A and DNA-B molecules of T217L were cloned and sequenced. The genome organization of T217L was identical to the bipartite genomes of other begomoviruses described from the Americas. Characteristic disease symptoms were reproduced in S. lycopersicum and Capsicum annum plants inoculated using the cloned viral DNA-A and DNA-B components, confirming disease aetiology. A sequence analysis of DNA-A showed that the T217L isolate has the highest sequence identity (84%) with sida yellow mosaic Yucatan virus (SiYMYuV), sida golden mosaic Honduras virus (SiGMHV) and bean dwarf mosaic virus (BDMV) isolates. This is less than the 89% identity in the DNA-A component that has been defined as the threshold value for the demarcation of species in the genus Begomovirus. The molecular data show that isolate T217L belongs to a novel tentative begomovirus species, for which the name tomato chlorotic leaf distortion virus is proposed. TCLDV was also detected in symptomatic C. chinense plants growing near the T217L-infected plant.     

Infectivity analysis of a blackgram isolate of <Emphasis Type="Italic">Mungbean yellow mosaic virus</Emphasis> and genetic assortment with MYMIV in selective hosts

Yellow mosaic disease in grain legumes in Indian subcontinent is caused by two important virus species viz. Mungbean yellow mosaic virus (MYMV) and Mungbean yellow mosaic India virus (MYMIV), belonging to the genus Begomovirus of the family Geminiviridae. The genomic components of a begomovirus causing yellow mosaic disease in blackgram in southern India were cloned and sequenced. Nucleotide sequence comparison of DNA A component shows the virus isolate to be a variant of Mungbean yellow mosaic virus:–(MYMV-[IN:Vam:05]). However, DNA B component of the present virus isolate has greater similarity (92%) to Mungbean yellow mosaic India virus. Agroinoculations of the viral clones produced typical yellow mosaic symptoms in blackgram and mungbean, severe leaf curl and stunting in French bean, similar to blackgram isolate of MYMIV. Blackgram isolates of both the virus species were only mildly infectious on cowpea, produced atypical leaf curl symptoms and not yellow or golden mosaic. In agroinoculations done by exchanging genomic components, symptom expression was seen only in French bean. In cowpea, blackgram and mungbean there was no visible symptoms though viral DNA could be detected by PCR.     

Molecular characterization and phylogenetic relationships of Desmodium leaf distortion virus (DeLDV): a new begomovirus infecting <Emphasis Type="Italic">Desmodium glabrum</Emphasis> in Yucatan,Mexico

The complete DNA-A component sequence of Desmodium leaf distortion virus (DeLDV, Begomovirus) isolated in Yucatan was determined to be 2569 nucleotides (nt) in length, and it was most closely related to Cotton leaf crumple virus-California (CLCrV-[Cal]), at 76%. The complete DNA-B component sequence was 2514 nt in length, and shared its highest nucleotide identity (60%) with Potato yellow mosaic Trinidad virus (PYMTV). Phylogenetic analyses group the DeLDV DNA-A component in the SLCV clade, whereas, the DeLDV DNA-B was grouped with the Abutilon mosaic virus clade, which also contains PYMV, suggesting that the DeLDV components have distinct evolutionary histories, possibly as the result of recombination and reassortment.     

Molecular characterization of a distinct begomovirus infecting tobacco in Yunnan, China

Summary.  Virus isolate Y3V, obtained from tobacco showing leaf curl symptoms in Yunnan, China, had particles with the size and morphology typical of geminiviruses. In reactions with a set of monoclonal antibodies raised against begomoviruses, Y3V was readily differentiated from two previously studied Chinese Begomovirus isolates. The complete nucleotide sequence of a DNA-A-like molecule of Y3V was determined; it comprises 2744 nucleotides and has a typical Begomovirus genome organization. When compared with the DNA-A sequences of other begomoviruses, the total DNA-A of Y3V was most closely related to that of Ageratum yellow vein virus (AYVV) (85% sequence identity), but the Y3V intergenic region differed greatly from those of the other sequences (maximum 70% identity). In contrast, the deduced coat protein of Y3V is most like that of Tomato yellow leaf curl Thailand virus-[1] (TYLCTHV-[1]) (92% amino acid sequence identity). The molecular data show that the Yunnan isolate of Tobacco leaf curl virus is a distinct Begomovirus species, for which the name Tobacco leaf curl Yunnan virus (TLCYnV) is proposed. Received February 27, 2001/Accepted May 29, 2001     

<Emphasis Type="Italic">Watermelon chlorotic stunt virus</Emphasis> (WmCSV): a serious disease threatening watermelon production in Jordan

The incidence of watermelon chlorotic stunt disease and the molecular characterization of the Jordanian isolate of Watermelon chlorotic stunt virus (WmCSV-[JO]) are described in this study. Symptomatic leaf samples obtained from watermelon (Citrullus lanatus Thunb.), melon (Cucumis melo L.), squash (Cucurbita pepo), cucumber (Cucumis sativus L.), and bottle gourd (Lagenaria siceraria) plants were tested for WmCSV-[JO] infection by PCR. The virus could be detected in 8 melon and 87 watermelon samples obtained from Ghor Assafi (southern part of Jordan Valley). Three samples collected from Mafraq (eastern part of Jordan) were found mixed infected with WmCSV-[JO] and Squash leaf curl virus. The full-length DNA-A and DNA-B genomes of WmCSV-[JO] were amplified, and sequences were deposited in the GenBank under accession numbers EU561237 and EU561236, respectively. Sequence analysis reveals that WmCSV-[JO] is closely related to other virus isolates from Israel (WmCSV-[IL]), Yemen (WmCSV-[YE]), Iran (WmCSV-[IR]), Lebanon (WmCSV-[LB]), and Sudan (WmCSV-[SD]). DNA-A of WmCSV-[JO] showed highest nucleotide identity (99.42%) with WmCSV-[IL], while DNA-B had highest nucleotide identity (95.52%) with WmCSV-[YE]. Data of this study demonstrate that digestion of DNA-B genome of WmCSV isolates with ApaI enzyme can discriminate between these isolates at the molecular level. Infectious clones of WmCSV-[JO] were constructed and agroinoculated to Nicotiana benthamiana plants. Inoculated plants developed mild disease symptoms 4 weeks post inoculation, while watermelon plants biolistically inoculated with WmCSV-[JO] developed characteristic mottling, yellowing and severe leaf curling symptoms 3 weeks post inoculation.     

Molecular identification of a new begomovirus associated with yellow mosaic disease of Jatropha gossypifolia in India

Yellow mosaic disease was observed on Jatropha gossypifolia plants growing in Kathaupahadi, Madhya Pradesh, India, and whiteflies (Bemisia tabaci) were found in the vicinity. Association of a new begomovirus with yellow mosaic disease of J. gossypifolia has been detected by PCR using begomovirus DNA-A-specific primers. The complete DNA-A genome (~2.7 kb) of this virus isolate was amplified by rolling-circle amplification (RCA) followed by digestion with Bam HI. The ~2.7-kb amplicons was cloned and sequenced, and the data obtained were submitted to GenBank under accession numbers FJ177030. The genome of the virus isolate consisted of six open reading frames (ORFs): V2 (pre-coat protein) and V1 (coat protein) in the virion sense and C3 (REn protein), C2 (TrAP protein), C1 (replication-associated protein) and C4 (C4 protein) in the complementary sense. BLASTn analysis of the nucleotide sequence (2757 nt) of the viral genome (FJ177030) showed 84–85% identity and a distinct phylogenetic relationship with DNA-A of tomato leaf curl virus-Bangalore II (U38239) and tomato leaf curl Karnataka virus (AY754812). Based on its 85% sequence identity to all other begomoviruses known to date and ICTV species demarcating criteria (< 88% identity), the name Jatropha yellow mosaic India virus (JYMIV) is proposed. JYMIV is considered to be monopartite, as neither DNA-B nor DNA-β components associated with begomoviruses were detected.     

Soybean chlorotic spot virus, a novel begomovirus infecting soybean in Brazil

A novel soybean-infecting begomovirus from Brazil was identified in Jaíba, in the state of Minas Gerais, and molecularly characterized. By using rolling-circle amplification-based cloning of viral DNAs, three DNA-A variants and a cognate DNA-B were isolated from infected samples. The DNA variants share more than 98 % sequence identity but have less than 89 % identity to other reported begomovirus, the limit for demarcation of new species. In a phylogenetic analysis, both DNA-A and DNA-B clustered with other Brazilian begomoviruses. Infectious cloned DNA-A and DNA-B components induced distinct symptoms in Solanaceae and Fabaceae species by biolistic inoculation. In soybean, the virus induced mild symptoms, i.e., chlorotic spots on the leaves, from which the name soybean chlorotic spot virus (SoCSV) was proposed. The most severe symptoms were displayed by common beans, which exhibited leaf distortion, blistering, interveinal chlorosis, mosaic and golden mosaic. The possibility that SoCSV may become a threat to bean production in Brazil is discussed.     

Molecular characterization and experimental host-range of two begomoviruses infecting <Emphasis Type="Italic">Clerodendrum cyrtophyllum</Emphasis> in China

Two begomovirus isolates (YX2-I and YX2-II) were identified from Clerodendrum cyrtophyllum showing yellow mosaic symptoms collected in Jiangsu province of China. Sequence analysis reveals that YX2-I is a distinct begomovirus species for which the name Clerodendrum golden mosaic Jiangsu virus (ClGMJSV-[CN:YX2:08]) is proposed. YX2-II is an isolate of bipartite begomovirus Clerodendrum golden mosaic China virus (ClGMCNV-[CN:YX2:08]). Infectious clones of the two viruses were constructed and agroinoculated into Nicotiana benthamiana, N. glutinosa, N. tabacum Samsun, Petunia hybrida, Solanum lycopersicum, Capsicum annuum, S. melongena, Glycine max and Gossypium hirsutum plants. ClGMJSV induced leaf curling and stunting symptoms in N. benthamiana, N. glutinosa, N. tabacum Samsun, and P. hybrida, and ClGMCNV infected N. benthamiana, N. glutinosa, and N. tabacum Samsun with severe symptoms and P. hybrida without obvious symptom. Latent infection in N. benthamiana, N. glutinosa, N. tabacum Samsun, and P. hybrida plants was observed when plants were inoculated with ClGMCNV DNA-A alone. In addition, we illustrated that ClGMCNV DNA-A was capable of interacting with the betasatellite associated with Tobacco curly shoot virus (TbCSB) to produce symptoms in N. benthamiana and N. glutinosa plants, and ClGMJSV could interact with TbCSB but not with ClGMCNV DNA-B in N. benthamiana plants.