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The diversity of Geminiviridae and Alphasatellitidae species in tomatoes was assessed via high-throughput sequencing of 154 symptomatic foliar samples collected from 2002 to 2017 across seven Brazilian biomes. The first pool (BP1) comprised 73 samples from the North (13), Northeast (36), and South (24) regions. Sixteen begomoviruses and one Topilevirus were detected in BP1. Four begomovirus-like contigs were identified as putative novel species (NS). NS#1 was reported in the semi-arid (Northeast) region and NS#2 and NS#4 in mild subtropical climates (South region), whereas NS#3 was detected in the warm and humid (North) region. The second pool (BP2) comprised 81 samples from Southeast (39) and Central-West (42) regions. Fourteen viruses and subviral agents were detected in BP2, including two topileviruses, a putative novel begomovirus (NS#5), and two alphasatellites occurring in continental highland areas. The five putative novel begomoviruses displayed strict endemic distributions. Conversely, tomato mottle leaf curl virus (a monopartite species) displayed the most widespread distribution occurring across the seven sampled biomes. The overall diversity and frequency of mixed infections were higher in susceptible (16 viruses + alphasatellites) in comparison to tolerant (carrying the Ty-1 or Ty-3 introgressions) samples, which displayed 9 viruses. This complex panorama reinforces the notion that the tomato-associated Geminiviridae diversity is yet underestimated in Neotropical regions.

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Cactaceae comprise a diverse and iconic group of flowering plants which are almost exclusively indigenous to the New World. The wide variety of growth forms found amongst the cacti have led to the trafficking of many species throughout the world as ornamentals. Despite the evolution and physiological properties of these plants having been extensively studied, little research has focused on cactus-associated viral communities. While only single-stranded RNA viruses had ever been reported in cacti, here we report the discovery of cactus-infecting single-stranded DNA viruses. These viruses all apparently belong to a single divergent species of the family Geminiviridae and have been tentatively named Opuntia virus 1 (OpV1). A total of 79 apparently complete OpV1 genomes were recovered from 31 different cactus plants (belonging to 20 different cactus species from both the Cactoideae and Opuntioideae clades) and from nine cactus-feeding cochineal insects (Dactylopius sp.) sampled in the USA and Mexico. These 79 OpV1 genomes all share > 78.4% nucleotide identity with one another and < 64.9% identity with previously characterized geminiviruses. Collectively, the OpV1 genomes display evidence of frequent recombination, with some genomes displaying up to five recombinant regions. In one case, recombinant regions span ~40% of the genome. We demonstrate that an infectious clone of an OpV1 genome can replicate in Nicotiana benthamiana and Opuntia microdasys. In addition to expanding the inventory of viruses that are known to infect cacti, the OpV1 group is so distantly related to other known geminiviruses that it likely represents a new geminivirus genus. It remains to be determined whether, like its cactus hosts, its geographical distribution spans the globe.

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Grapevine red blotch virus (GRBV) is an emerging virus of significant viticultural importance throughout North America. Here, we report the development of a simple protocol for point-of-use detection of GRBV. Extraction of nucleic acids is not required; instead, the whole intact plant can simply be pricked with a sterile pipette tip, which is then incubated in sterile distilled water to provide the sample template in a loop-mediated isothermal amplification (LAMP) reaction. This method is 10,000 times more sensitive than conventional PCR, costs under a dollar per sample, and can be completed from sampling to readout in just over half an hour.

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Beet mild curly top virus (BMCTV) is associated with an outbreak of curly top in chili pepper, tomato and other Solanaceae species, which can cause severe crop losses. The aim of this work was to obtain the 1H NMR metabolomic profiling of both healthy chili peppers (cv. mirasol) and infected chili peppers with BMCTV in order to find chemical markers associated to the infection process. Significant differences were found between the two groups, according to principal component analysis and orthogonal projections to latent structure discriminant analysis. Compared to the asymptomatic peppers, the symptomatic fruits had higher relative abundance of fructose, isoleucine, histidine, phenylalanine and tryptophan. Contrarily, the asymptomatic samples showed greater amounts of malonate and isobutyrate. These results suggest that in diseased chili peppers there are metabolic changes related to the viral acquisition of energy for replication and capsid assembly. This is the first study describing the chemical profiling of a polar extract obtained from Capsicum annuum infected by BMCTV under open field conditions.

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We investigated the molecular characteristics of an Argentinean isolate of alfalfa leaf curl virus (ALCV-Arg), a virus of the genus Capulavirus in the family Geminiviridae that was isolated from alfalfa plants showing dwarfism. The genome was found to be 2,750 nucleotides in length. In pairwise comparisons, this ALCV isolate shared 83.2% to 92.6% sequence identity with European ALCV isolates. Sequence comparisons and phylogenetic analysis showed that this isolate combines features of strains A and B of ALCV. Recombination analysis showed that ALCV-Arg is a recombinant isolate that was generated by intraspecific recombination between ALCV strains A and B. The results of this study not only show that ALCV-Arg is unique because it combines features of strains A and B but also show that ALCV naturally infects this forage crop on the American continent.

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In fall 2014, 5 to 75% percent of chili and bell pepper (Capsicum annuum L.) in commercial fields located in the Mexican states of Durango, Zacatecas, and Michoacán had symptoms of deformed, small, mosaic, curled, and chlorotic leaves; shortened internodes; plant dwarfing; or phyllody and rosetting leaf tips. At the same time, leafhoppers and psyllids were observed in the fields, and more than 50 beet leafhoppers (Circulifer tenellus) and nearly 300 potato psyllids (Bactericera cockerelli) were collected from the pepper plants and adjacent weeds. Based on the insect pressure and observed symptoms, nearly 400 pepper samples were collected across this region of Mexico and tested for the presence of leafhopper- and psyllid-associated pathogens. In all, 76% of the pepper samples were found to be infected with 'Candidatus Liberibacter solanacearum', beet leafhopper-transmitted virescence agent (BLTVA) phytoplasma, a strain of a curtovirus, or a combination of any two or three of these pathogens. Additionally, 77% of the collected leafhoppers and 40% of the psyllids were infected with one or more of these pathogens, in addition to Spiroplasma citri. Specifically, the leafhoppers were infected with BLTVA phytoplasma, S. citri, or a strain of curtovirus. Of particular interest, potato psyllids were not only infected with 'Ca. L. solanacearum' but also with phytoplasmas that belong to the groups 16SrVI subgroup A and 16SrI subgroup A. The presence of mixed infections in pepper plants and the insect vectors highlights the need for growers to effectively control both leafhoppers and potato psyllids from solanaceous crops in this region of Mexico in order to prevent the spread of these bacterial and viral pathogens.

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Viruses in the family Geminiviridae have single-stranded DNA genomes encapsulated in geminate icosahedral particles. High throughput sequencing (HTS) for metagenomic approaches are being extensively used for the identification of known and novel viruses. Using a HTS approach, we identified a novel geminivirus in a tomato (Solanum lycopersicum) sample and a Cleome sp. sample collected in the midwest region of Brazil. The genomes from the two samples share 99.96% identity and ∼61-63% to genomes in the genus Capulavirus. The novel virus has been tentatively named tomato associated geminivirus 1 (TaGV1). No visual symptoms were observed in the field tomato plant or in the inoculated Nicotiana benthamiana where the virus established a systemic infection. The replication associated protein of TaGV1 is most similar to that encoded by capulaviruses (sharing 62-70% identity), whereas the CP is most similar to that of tomato pseudo curly top virus (sharing ∼31% identity). In the TaGV1 positive Cleome sp. sample, begomovirus DNA A and B components were also detected sharing 96% and 90% sequence identity to cleome leaf crumple virus DNA A and B components, respectively. Using a HTS approach, we identified TaGV1 in tomato and Cleome sp. samples and this is the first report of a geminivirus that is non-begomovirus in Brazil.

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BACKGROUND: In Africa and Asia, sugarcane is the host of at least seven different virus species in the genus Mastrevirus of the family Geminiviridae. However, with the exception of Sugarcane white streak virus in Barbados, no other sugarcane-infecting mastrevirus has been reported in the New World. Conservation and exchange of sugarcane germplasm using stalk cuttings facilitates the spread of sugarcane-infecting viruses. METHODS: A virion-associated nucleic acids (VANA)-based metagenomics approach was used to detect mastrevirus sequences in 717 sugarcane samples from Florida (USA), Guadeloupe (French West Indies), and Réunion (Mascarene Islands). Contig assembly was performed using CAP3 and sequence searches using BLASTn and BLASTx. Mastrevirus full genomes were enriched from total DNA by rolling circle amplification, cloned and sequenced. Nucleotide and amino acid sequence identities were determined using SDT v1.2. Phylogenetic analyses were conducted using MEGA6 and PHYML3. RESULTS: We identified a new sugarcane-infecting mastrevirus in six plants sampled from germplasm collections in Florida and Guadeloupe. Full genome sequences were determined and analyzed for three virus isolates from Florida, and three from Guadeloupe. These six genomes share >88% genome-wide pairwise identity with one another and between 89 and 97% identity with a recently identified mastrevirus (KR150789) from a sugarcane plant sampled in China. Sequences similar to these were also identified in sugarcane plants in Réunion. CONCLUSIONS: As these virus isolates share <64% genome-wide identity with all other known mastreviruses, we propose classifying them within a new mastrevirus species named Sugarcane striate virus. This is the first report of sugarcane striate virus (SCStV) in the Western Hemisphere, a virus that most likely originated in Asia. The distribution, vector, and impact of SCStV on sugarcane production remains to be determined.

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The RNAi concept was explored to silence the rep gene from the bean golden mosaic virus (BGMV) and a genetically modified (GM) bean immune to the virus was previously generated. We investigated if BGMV-viruliferous whiteflies would reduce viral amount after feeding on GM plants. BGMV DNA amount was significantly reduced in whiteflies feeding in GM-plants (compared with insects feeding on non-GM plants) for a period of 4 and 8 days in 52% and 84% respectively.

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Circomics (circular DNA genomics), the combination of rolling circle amplification (RCA), restriction fragment length polymorphism (RFLP) analysis and pyro-sequencing, has been used recently to identify geminiviruses with high efficiency and low costs. Circular DNAs associated with Cuban geminiviruses were characterised by RCA/RFLP analysis and 454 sequencing of two batches of DNA amplified from selected plant samples as well as individual cloning and Sanger sequencing of DNA components and compared to other geminiviral DNAs by phylogenetic analysis. Cuban geminiviruses that were closely related to each other challenged the circomics approach. Ten geminiviral components and one alpha-satellite DNA were determined and compared to three geminiviral components obtained by conventional cloning. New strains of Sida yellow mottle virus (SiYMoV), tomato yellow distortion leaf virus (ToYDLV), Sida golden mosaic Florida virus (SiGMFV) and Sida golden mosaic Liguanea virus (SiGMLV) are described with host plant species being classified by molecular PCR-based bar coding. A new virus species is named Peristrophe mosaic virus. The first alpha-satellite found in Middle America establishes the New World branch of these elements which are related to nanoviruses and were previously thought to be restricted to the Old World. In conclusion, circomics is efficient for complex infections and closely related viruses to detected unexpected viral DNAs, but may need some scrutinisation by direct sequencing and cloning of individual components for certain cases.

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La transmisión experimental de Begomovirus es problemática. La mayoría de estos virus se pueden transmitir de planta a planta por su vector biológico, Bemisia tabaci. Las inoculaciones experimentales con mosca blanca son problemáticas debido a sus hábitos de alimentación, requerimiento de una planta viva infectada e instalaciones de contención para el vector. Por su parte la inoculación mecánica de Begomovirus es posible, pero generalmente a tasas bajas y no en todos los casos. Por esta razón el bombardeo de partículas (biobalística) de DNA viral como una estrategia de inoculación fue desarrollada. La posibilidad de utilizar el dispositivo de mano Helios Gen Gun System (Biorad®), un equipo de biobalística, para la transmisión de un Begomovirus bipartita a plantas de tomate y tabaco fue ensayado y optimizado. Los parámetros evaluados fueron: número de disparos (1-2), presión de helio (220 y 320 psi) y diámetro de las partículas de oro (0.6 y 1.6µm). Los síntomas característicos de la enfermedad viral (clorosis, mosaico y deformación de la hoja) aparecieron 3 semanas después del bombardeo en las hojas jóvenes no inoculadas. La replicación del DNA viral en las plantas se confirmó por Reacción en cadena de la polimerasa. Plantas infectadas en un 100 se obtuvieron cuando en el bombardeo se emplearon partículas de oro de 1.6 µm recubiertas con DNA viral a una presión de 320psi. A nuestro entender este es el primer reporte en Colombia de la inoculación directa de plantas de tomate y tabaco con un Begomovirus bipartita usando un dispositivo portátil de biobalística.

Experimental transmission of Begomovirus is problematic. Most Begomoviruses can be transmitted readily from plant to plant by the whitefly vector, but this also requires a live infected plant and extensive facilities to maintain the insect. Whitefly inoculations can also be problematic because of their preferential feeding habits on certain plants. Mechanical inoculation of Begomovirus is possible but generally at low rates and for others not at all. For this reason particle bombardment (biolistic) of DNA viral as an inoculum was developed. The possibility of using the Helios Gen Gun System (Biorad®), a biolistic hand-held device, for transmitting Begomovirus bipartite to tomato and tobacco plants was assayed and optimized. Biolistic inoculation was carried out with the hand held device at 220 or 320 psi, applying 1 or 2 shots /plant and using gold particles of 0.6 or 1.6µm in size. Characteristic symptoms of viral disease (chlorosis, mosaic and leaf deformation) appeared 3 weeks post-inoculation in the newly developing leaves. Replication of the viral DNA in plants was confirmed by Polymerase Chain Reaction. All bombarded plants became infected when biolistic inoculation was carried out with the hand held device at 320psi and using 1.6 µm gold particles in size. To our knowledge this is the first report in Colombia of successful direct inoculation of tomato and tobacco plants with Begomovirus bipartite geminivirus using a biolistic hand-held device.

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Begomoviruses cause major diseases of sweet potato worldwide impairing considerably the yields of this important food staple. Since sweet potato plants are vegetatively propagated and globally transported, they are prone to accumulate and disseminate geminiviruses. Effective diagnostic tools are, therefore, desirable. We studied the genomic diversity of geminiviruses present in naturally-infected sweet potato accessions belonging to a Brazilian germplasm bank collection. Fifty-five samples from different sweet potato accessions displaying geminivirus-like symptoms were analyzed by combining rolling circle amplification (RCA) with restriction fragment length polymorphism (RFLP) and sequencing. The restriction enzyme MspI (HpaII) revealed diverse band patterns in 55 samples and digestion with BamHI, SstI or PstI resulted in full-length sweet potato geminivirus DNAs of about 3 kb in 46 samples. In addition, smaller fragments were identified as either viral "Defective DNAs" (D-DNAs) or mitochondrial plasmid DNAs. The diversity of sweet potato-associated geminiviruses was found to be very high under Brazilian conditions. Representative viral full-length DNAs have been cloned and sequenced yielding two new tentative species, three strains and several variants of previously described sweet potato geminiviruses. Sequence comparisons identified footprints of recombination in their genomes underscoring the risk of generating new geminiviruses in vegetatively propagated germplasm bank material. The sites of recombination were found in conjunction with predicted hairpin structures. We propose diagnostic routines to screen germplasm bank material for geminiviruses by the rapid and reliable RCA/RFLP as the technique of choice.

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Over 4,950 asymptomatic weed samples from more than 20 weed species that are host plants for curtoviruses were collected from ten chile pepper fields in southern New Mexico (NM) during 2003, 2004 and 2005 to identify whether they were infected with curtoviruses and to determine which curtoviruses were distributed in the weed population. Polymerase chain reaction using primers designed to detect a portion of the coat protein (cp) gene were used to detect curtoviruses, and infected plants were further tested for specific curtoviruses using primers designed to detect to a portion of the replication-associated protein (rep) gene. Amplification of the cp gene was successful from 3.7, 1.17, and 1.9% of the weed samples in 2003, 2004, and 2005, respectively. Seventy-three amplicons from those samples were sequenced and compared to well-characterized curtoviruses. Analysis of the rep nucleotide sequences showed that approximately 32.9% of the weed isolates tested were closely related to beet mild curly top virus (BMCTV). Approximately 12.4% were closely related to beet severe curly top virus (BSCTV). The rest of the weed isolates (54.7%), which shared a very high level of nucleotide sequence identity to each other, represent a new curtovirus species. Using eight primers designed for PCR, complete genomes of three curtoviruses isolated from chile pepper samples representing the three groups of curtoviruses in southern New Mexico were sequenced. Comparisons of whole sequences of the genomes revealed that the DG2SW171601 isolate (2,929 nucleotides) was nearly identical to BMCTV-W4 (approximately 98% nucleotide sequence identity). The LRME27601 isolate (2,927 nucleotides) was most closely related to BSCTV (approximately 92% nucleotide sequence identity). The LJN17601 isolate (2,959 nucleotides) shared only from 49.9 to 88.8% nucleotide sequence identity with other well-characterized curtoviruses. Based on the accepted cut-off of 89%, we propose that the LJN17601 isolate is a member of a new curtovirus species. Chile peppers infected with this virus in the field express chlorotic stunting symptoms, so we propose the name pepper yellow dwarf virus (PeYDV). This new curtovirus species may be the result of mutations in the genome and recombination between BMCTV-W4 and BSCTV.

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BACKGROUND: Viruses that have spent most of their evolutionary time associated with a single host lineage should have sequences that reflect codivergence of virus and host. Several examples for RNA viruses of host-virus tree congruence are being challenged. DNA viruses, such as mastreviruses, are more likely than RNA viruses to have maintained a record of host lineage association. RESULTS: The full genomes of 28 isolates of Wheat dwarf virus (WDV), a member of the Mastrevirus genus, from different regions of China were sequenced. The analysis of these 28 entire genomes and 18 entire genome sequences of cereal mastreviruses from other countries support the designation of wheat, barley and oat mastrevirus isolates as separate species. They revealed that relative divergence times for the viruses WDV, Barley dwarf virus (BDV), Oat dwarf virus (ODV) and Maize streak virus (MSV) are proportional to divergence times of their hosts, suggesting codivergence. Considerable diversity among Chinese isolates was found and was concentrated in hot spots in the Rep A, SIR, LIR, and intron regions in WDV genomes. Two probable recombination events were detected in Chinese WDV isolates. Analysis including further Mastrevirus genomes concentrated on coding regions to avoid difficulties due to recombination and hyperdiversity. The analysis demonstrated congruence of trees in two branches of the genus, but not in the third. Assuming codivergence, an evolutionary rate of 10-8 substitutions per site per year was calculated. The low rate implies stronger constraints against change than are obtained by other methods of estimating the rate. CONCLUSION: We report tests of the hypothesis that mastreviruses have codiverged with their monocotyledonous hosts over 50 million years of evolution. The tests support the hypothesis for WDV, BDV and ODV, but not for MSV and other African streak viruses.

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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.

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The begomovirus Potato yellow mosaic virus (PYMV) is responsible of significant yield losses in tomato in Guadeloupe. Four field isolates from Guadeloupe were analyzed in term of their host range using three inoculation methods (mechanical, grafting and insect vector), sequences analysis of PCR fragments and phylogenetic analysis of an infectious clone, PYMV-[GP]. Capsicum annuum, Datura stramonium, Nicotiana benthamiana, N. tabacum 'Xanthi NC', Petunia hybrida, and Solanum tuberosum were found to be hosts. All isolates from Guadeloupe, Martinique, Puerto Rico and the Dominican Republic were closely related to PYMV-[GP]. Sequence identity between PYMV-[GP] and PYMV-Ve from Venezuela and PYMTV from Trinidad and Tobago clearly confirmed that it is a new strain of PYMV.

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Tomato-infecting begomoviruses have been reported throughout Brazil since the introduction of the B biotype of Bemisia tabaci. Here, we report a large scale survey on the distribution and genetic diversity of tomato-infecting begomoviruses. Tomato samples with typical begomovirus symptoms were collected in seven different states, comprising the major tomato growing areas of the country. Viruses were detected by polymerase chain reaction (PCR) using universal primers for the genus Begomovirus. PCR-amplified fragments were cloned and sequenced. Based on sequence comparisons and phylogenetic analyses, at least seven previously undescribed species of begomoviruses were found. Four of the new viruses were found exclusively in the Southeastern states, two exclusively in the Northeastern states, and one was found in both regions. Sequence comparisons reveal strong evidence of recombination among the Brazilian begomoviruses. Together, the results indicate the existence of a high degree of pre-existing genetic diversity among tomato-infecting begomoviruses in Brazil and suggest that these viruses have emerged after being transferred from natural hosts to tomatoes, due to the introduction into Brazil of a novel polyfagous biotype of the whitefly vector.

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Biological differences and molecular variability between six phenotypically distinct tobacco-infecting geminivirus isolates from southern Africa (Zimbabwe) and Mexico were investigated. Host range studies conducted with tobacco virus isolates ZIM H from Zimbabwe and MEX 15 and MEX 32 from Mexico indicated all had narrow host ranges restricted to the Solanaceae. Alignment of coat protein gene (CP) and common region (CR) sequences obtained by PCR, and phylogenetic analysis of the CP sequences indicated Zimbabwean isolates were distantly related to those from Mexico and that geographically proximal isolates shared their closest affinities with Old and New World geminiviruses, respectively. Zimbabwean isolates formed a distinct cluster of closely related variants (> 98% sequence identity) of the same species, while MEX 15 segregated independently from MEX 32, the former constituting a distinct species among New World geminiviruses, and the latter being a variant, Texas pepper virus-Chiapas isolate (TPV-CPS) with 95% sequence identity to TPV-TAM. Results collectively indicated a geographic basis for phylogenetic relationships rather than a specific affiliation with tobacco as a natural host. MEX 15 is provisionally described as a new begomovirus, tobacco apical stunt virus, TbASV, whose closest CP relative is cabbage leaf curl virus, and ZIM isolates are provisionally designated as tobacco leaf curl virus, TbLCV-ZIM, a new Eastern Hemisphere begomovirus, which has as its closest relative, chayote mosaic virus from Nigeria.

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The cloning and nucleotide sequence of a new bipartite geminivirus found in Cuba is described. DNA A (2620 nt) and DNA B (2586 nt) presented a genomic structure resembling that of other geminiviruses transmitted by Bemisia tabaci. Both components had a common region of 168 nt with a 95% identity. Typical elements involved in replication and transcription were found in this region, though group-characteristic arrangement of iterons was not conserved in this virus. Sequence was compared with geminivirus sequences deposited in the GenBank. Interestingly, when total DNAs or individual ORFs and deduced amino acid sequences were compared, the highest scores were for different viruses. It showed to be most closely related to tomato mottle virus (81.9% and 65.5% similarity with DNAs A and B, respectively) and a member of the abutilon mosaic cluster of New World Begomoviruses. When clones A and B were co-agroinoculated they resulted highly infectious and induced symptoms in Nicotiana benthamiana plants. The A component alone was infectious but induced only mild symptoms, while the B component was not infectious. The presence of viral DNA in N. benthamiana plants was confirmed by dot-blot hybridization using specific probes. These data show that the cuban isolate is a new geminivirus for which the name of Havana tomato virus is proposed.

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The nucleotide sequence of infectious clones of a geminivirus from Costa Rica that infects Sida rhombifolia was determined. Sida golden mosaic virus (SiGMV-Co) has a bipartite genome (DNAs A and B). Computer analysis showed that the bipartite genome of SiGMV-Co resembles that of other whitefly-transmitted geminiviruses. The DNA A (2605 nt) and DNA B (2587 nt) components have little sequence homology other than within the common region (CR). Analysis of DNAs A and B showed that SiGMV-Co is closely related to bean dwarf mosaic virus (BDMV). SiGMV-Co was introduced via agroinoculation into seven plant species, including tomato and bean.

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