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1.
Arch Virol ; 165(3): 775-779, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31919592

RESUMO

Two begomovirus-associated alphasatellites were isolated from okra and a malvastrum plant (Malvaceae) in Cameroon. The complete nucleotide sequences of the okra- and malvastrum-infecting alphasatellites were 1375 and 1416-1418 nucleotides, respectively, and both exhibited features characteristic of other alphasatellites. Based on pairwise sequence comparisons, these previously undescribed alphasatellites are members of distinct species in the genera Colecusatellite and Gosmusatellite and have been tentatively named "pepper yellow vein Mali alphasatellite" and "cotton leaf curl Gezira alphasatellite3", respectively. Taken together with previous studies, alphasatellites endemic to Cameroon appear to be more diverse and infect plants of many more species and families than currently recognized.


Assuntos
Abelmoschus/virologia , Begomovirus/classificação , Begomovirus/genética , Malvaceae/virologia , Sequência de Bases , Begomovirus/isolamento & purificação , Camarões , DNA Viral/genética , Doenças das Plantas/virologia , Análise de Sequência de DNA , Proteínas Virais/genética
2.
Arch Virol ; 164(11): 2873-2875, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31432269

RESUMO

A novel bipartite begomovirus infecting begomovirus-resistant tomato plants was detected via Illumina sequencing analysis, and its genome sequence was confirmed by Sanger sequencing. The DNA-A (2627 nt) and DNA-B (2587 nt) have a genome organization that is typical of New World bipartite begomoviruses, sharing 82.5% identity with tomato golden leaf distortion virus and 75.1% identity with sida chlorotic vein virus. Based on the current classification criteria for begomoviruses, this isolate should be considered a member of a new species, and the name "tomato interveinal chlorosis virus-2" (ToICV2) is proposed for this virus.


Assuntos
Begomovirus/classificação , Begomovirus/genética , Genoma Viral/genética , Lycopersicon esculentum/virologia , Sequência de Bases , Begomovirus/isolamento & purificação , Brasil , DNA Viral/genética , Doenças das Plantas/virologia , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
3.
Arch Virol ; 164(9): 2379-2383, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31203434

RESUMO

During 2017, leaf samples of chili pepper (Capsicum annuum), tomato (Solanum lycopersicum), and tobacco (Nicotiana tabacum) plants exhibiting yellowing and curling symptoms were collected from Aceh province, Indonesia. These samples were used to isolate and sequence viral genomic DNA. Six isolates with complete DNA-A and DNA-B sequences of begomovirus were obtained, all of which showed >99% sequence identity to the others. DNA-A sequences shared the highest nucleotide sequence identity (89.3%-89.7%) with monopartite pepper yellow leaf curl Indonesia virus 2 (PepYLCIV2) and the second-highest sequence identity (87.3%-87.4%) with bipartite pepper yellow leaf curl Indonesia virus (PepYLCIV). The DNA-B sequences shared the highest nucleotide sequence identity (95%-97.5%) with PepYLCIV. Results of recombination analysis indicated that the novel begomovirus was a recombinant. In accordance with the guidelines for begomovirus species demarcation, these isolates should be assigned to a new species, and we have proposed the name ''pepper yellow leaf curl Aceh virus'' (PepYLCAV) for this virus.


Assuntos
Begomovirus/isolamento & purificação , Capsicum/virologia , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Tabaco/virologia , Begomovirus/classificação , Begomovirus/genética , Genoma Viral , Indonésia , Filogenia , Recombinação Genética , Análise de Sequência de DNA
4.
Arch Virol ; 164(7): 1907-1910, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30972591

RESUMO

A new bipartite begomovirus (family Geminiviridae) was detected on cowpea (Vigna unguiculata) plants exhibiting bright golden mosaic symptoms on leaves under field conditions in Brazil. Complete consensus sequences of DNA-A and DNA-B components of an isolate of the virus (PE-088) were obtained by nanopore sequencing and confirmed by Sanger sequencing. The genome components presented the typical genomic organization of New World (NW) begomoviruses. Pairwise sequence comparisons revealed low levels of identity with other begomovirus species previously reported infecting cowpea around the world. Phylogenetic analysis using complete sequences of DNA-A components revealed that the closest relatives of PE-088 (85-87% nucleotide sequence identities) were three legume-infecting begomoviruses from Brazil: bean golden mosaic virus, macroptilium common mosaic virus and macroptilium yellow vein virus. According to the current classification criteria, PE-088 represents a new species in the genus Begomovirus, tentatively named as cowpea bright yellow mosaic virus (CoBYMV).


Assuntos
Begomovirus/classificação , Begomovirus/genética , Genoma Viral/genética , Doenças das Plantas/virologia , Folhas de Planta/virologia , Vigna/virologia , Sequência de Bases , Begomovirus/isolamento & purificação , DNA Viral/genética , Filogenia , Análise de Sequência de DNA
5.
Arch Virol ; 164(7): 1897-1901, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30972592

RESUMO

Two begomoviruses were isolated in the northern Brazilian state of Pará, infecting non-cultivated Hibiscus sp. and cultivated tomato (Solanum lycopersicum). The complete genomes (DNA-A and DNA-B) of the two viruses showed the typical organization of New World bipartite begomoviruses. Based on the species assignment criteria in the genus Begomovirus, each virus is a member of a new species. The virus from Hibiscus is most closely related to sida yellow mosaic Yucatan virus, while the tomato virus is most closely related to abutilon mosaic Brazil virus and corchorus mottle virus. Recombination events were detected in the DNA-A of the tomato virus, but not in the Hibiscus virus genome. We propose the names "hibiscus golden mosaic virus" (HGMV) and "tomato chlorotic leaf curl virus" (ToCLCV) for the viruses reported in this study.


Assuntos
Begomovirus/classificação , Begomovirus/genética , Hibiscus/virologia , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Begomovirus/isolamento & purificação , Brasil , DNA Viral/genética , Genoma Viral/genética , Homologia de Sequência do Ácido Nucleico
6.
Arch Virol ; 164(6): 1661-1665, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30949815

RESUMO

Forty-five papaya samples showing severe leaf curl symptoms were tested by PCR with a degenerate primer set for virus species in the genus Begomovirus. Of these, 29 were positive for tomato leaf curl Bangladesh virus (ToLCBV). The complete genome sequences of ToLCBV (GenBank accession no. MH380003) and its associated tomato leaf curl betasatellite (ToLCB) (MH397223) from papaya isolate Gaz17-Pap were determined and characterized. Defective betasatellites were found in ToLCBV-positive papaya isolates Gaz19-Pap, Gaz20-Pap and Gaz21-Pap. This study confirmed that papaya is a host of ToLCBV, ToLCB, and other defective and recombinant DNA satellites in Bangladesh.


Assuntos
Begomovirus/isolamento & purificação , Carica/virologia , Doenças das Plantas/virologia , Análise de Sequência de DNA/métodos , Bangladesh , Begomovirus/genética , Begomovirus/patogenicidade , Genoma Viral , Lycopersicon esculentum/virologia , Filogenia , Vírus Satélites/genética , Vírus Satélites/isolamento & purificação , Vírus Satélites/patogenicidade
7.
BMC Genomics ; 20(1): 274, 2019 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-30954067

RESUMO

BACKGROUND: Cotton leaf curl disease (CLCuD), caused by begomoviruses in association with satellite molecules, is a major threat to cotton production causing enormous losses to cotton crop in most of the cotton growing countries including Indian subcontinent. In this study, isolates of begomovirus and satellite molecules associated with CLCuD were collected from North India (Haryana, New Delhi). They were amplified employing rolling circle replication mechanism, cloned, sequenced and, their phylogenetic and recombination analysis was performed. RESULTS: The five Cotton leaf curl Multan virus (CLCuMuV) isolates investigated in this study showed monopartite organization of the genome typical of Old World begomoviruses. Nucleotide sequence analyses assigned them as the strains of CLCuMuV and were designated as CLCuMuV-SR13, CLCuMuV-SR14, CLCuMuV-ND14, CLCuMuV-ND15 and CLCuMuV-SR15. The genome of CLCuMuV-SR13 shared a highest level of nucleotide sequence identity (98%) with CLCuMuV (JN678804), CLCuMuV-SR14 and CLCuMuV-SR15 exhibited 96% with CLCuMuV (KM096471), while isolates CLCuMuV-ND15 and CLCuMuV-SR15 revealed 96% sequence identity with CLCuMuV (AY765253). The four betasatellite molecules investigated in this study shared 95-99% nucleotide sequence identity with Cotton leaf curl Multan betasatellite (CLCuMB) from India. The betasatellite molecules were designated as CLCuMB-SR13, CLCuMB-SR14, CLCuMB-ND14 and CLCuMB-ND15. Alphasatellite molecules in this study, designated as GLCuA-SR14, GLCuA-ND14 and GLCuA-SR15, revealed 98% identity with Guar leaf curl alphasatellite (GLCuA) reported from Pakistan. CONCLUSION: The phylogenetic and recombination studies concluded that the isolates of CLCuMuV genomes undertaken in this study have a potential recombinant origin. Remarkably, significant recombination was detected in almost all the genes with contribution of Cotton leaf curl Kokhran Virus (CLCuKoV) in IR, V1, V2, C1, C4 and C5 regions and of CLCuMuV in C2 region of CLCuMuV-SR14. CLCuKoV also donated in C2, C3 regions of CLCuMuV-ND14; V1, V2, C2 and C3 regions of CLCuMuV-ND15 and C1 of CLCuMuV-SR15. Altogether, these observations signify the uniqueness in Indian CLCuMuV isolates showing contribution of CLCuKoV in all the genes. An interesting observation was frequent identification of GLCuA in CLCuD leaf samples.


Assuntos
Begomovirus/genética , DNA Satélite , Doenças das Plantas/virologia , Folhas de Planta/virologia , Recombinação Genética , Tabaco/virologia , Begomovirus/classificação , Begomovirus/isolamento & purificação , Índia , Filogenia , Análise de Sequência de DNA
8.
J Virol Methods ; 265: 71-76, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30321578

RESUMO

The emergence of begomovirus infection is one of the most important problems affecting production of a variety of vegetable crops worldwide. Infection by begomoviruses has been detected and spread rapidly on Cucurbitaceae and Solanaceae plants in Indonesia. A rapid and simple detection assay for begomoviruses under field conditions for routine sampling of plants is needed. Primers for a loop-mediated isothermal amplification (LAMP) assay were designed based on the sequences of three Indonesian begomoviruses, namely Tomato leaf curl New Delhi virus (ToLCNDV), Pepper yellow leaf curl Indonesia virus (PepYLCIV), and Tomato yellow leaf curl Kanchanaburi virus (TYLCKaV), infecting Cucurbitaceae and Solanaceae plants. LAMP assays using a Genelyzer™ III portable fluorometer with a toothpick method successfully detected these begomoviruses in infected melon, pepper, and eggplant samples. LAMP assays conducted during a field survey for detection of the three begomoviruses on 104 fresh leaves indicated that most of the samples were positive; the findings were confirmed by PCR using universal primers of begomovirus as a common detection method. These results demonstrate that this simple and rapid LAMP assay using a fluorometer portable device may be used to achieve real-time detection of begomoviruses under field conditions.


Assuntos
Begomovirus/isolamento & purificação , Cucurbitaceae/virologia , Fluorometria/instrumentação , Fluorometria/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Doenças das Plantas/virologia , Solanaceae/virologia , Begomovirus/genética , Primers do DNA/genética , Indonésia , Folhas de Planta/virologia , Fatores de Tempo
9.
J Virol Methods ; 263: 81-87, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30359678

RESUMO

A loop-mediated isothermal amplification (LAMP) assay was optimized for the detection of Mesta yellow vein mosaic virus (MeYVMV) in diseased plants of mesta (Hibiscus sabdariffa L.& H. cannabinus L.). The LAMP assay was optimized using a set of six primers targeting the MeYVMV genome and could be completed in 30-60 min at 63 °C. The LAMP amplification results were visualized by adding 1 µl of hydroxy naphthol blue (HNB) dye in a 25 µl LAMP reaction mixture prior to amplification as well as by electrophoresis. The LAMP assay, which detected MeYVMV in a 10-5-fold diluted total DNA, was more sensitive than the PCR assay (10-4-fold dilution). The optimized LAMP assay was able to detect MeYVMV in different parts of the kenaf and roselle plants. Similarly, the optimized PCR assay was also capable of detecting MeYVMV in all the different parts of the kenaf plant but failed to detect the virus in the stem and flower buds of the roselle plant. Validation of the LAMP and LAMP with HNB dye assays revealed that the optimized reactions can be used successfully for the in-situ detection of MeYVMV in field samples and in virus quarantine programs. This is the first report of the detection of the begomovirus species, MeYVMV, in the mucilaginous plant species, kenaf and roselle, using a LAMP assay.


Assuntos
Begomovirus/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico , Doenças das Plantas/virologia , Begomovirus/genética , Hibiscus/virologia , Naftalenossulfonatos , Técnicas de Amplificação de Ácido Nucleico/normas , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Microb Pathog ; 128: 82-89, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30583019

RESUMO

A begomovirus isolate collected from bitter gourd plants showing yellowing, puckering and stunting symptoms from Coimbatore district, Tamil Nadu, India was characterized. The full-length genome of the virus isolate was amplified by rolling circle amplification using phi29 DNA polymerase. The virus isolate exhibited 98% identity in the nucleotide sequence of DNA-A component with the Coccinia mosaic Virudhunagar virus (GenBank accession no. KY860899). The DNA-B component was very distinct and shared only 60% identity with the begomovirus, Coccinia mosaic Tamil Nadu virus (GenBank accession no. KM244719). The virus renamed as new species Bitter gourd yellow mosaic virus (BgYMV) was detected in seeds from infected plants and in the grow-out test seedlings by ELISA and virus-specific PCR. The seed infectivity was 79.16% and transmission rate to seedling was 32.05%. The virus titre as indicated by A405 absorption value was high (0.854-0.280) in different seed parts. Results clearly indicated seed transmission of the begomovirus, BgYMV.


Assuntos
Begomovirus/classificação , Begomovirus/genética , Begomovirus/isolamento & purificação , Transmissão de Doença Infecciosa , Momordica charantia/virologia , Filogenia , Doenças das Plantas/virologia , Sementes/virologia , Sequência de Bases , Clonagem Molecular , DNA Viral , Frutas , Genoma Viral , Índia , Folhas de Planta/virologia , Plântula/virologia , Análise de Sequência de DNA , Especificidade da Espécie
11.
Virus Res ; 258: 81-91, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30336187

RESUMO

Chayote (Sechium edule (Jacq. Sw.) is a single seeded cucurbitaceous vegetable crop mainly grown for its fruit. During 2015-2016, mosaic and leaf distortion type of symptoms were observed in chayote plants in hilly regions of Tamil Nadu. The disease incidence was 50. 3-100% and yield loss was about 69.9% in Dindigul district. The infected chayote plants showed yellow spots, yellow mosaic, leaf curling, puckering, and enations. The fruits of infected plants were malformed and were not marketable. The begomovirus causing the disease was identified as a variant of tomato leaf curl New Delhi virus. The chayote isolates of ToLCNDV share only 91 to 92% identity with other ToLCNDV isolates, deserving to be designated as distinct strain. The phylogenetic analysis on the basis of DNA A component nucleotides clearly indicated common origin of chayote, ridge gourd, ash gourd isolates of India along with Spanish isolates of ToLCNDV. This was contrasting to diverse origin of ToLCNDV isolates from other countries. The virus was sap transmissible to selected cucurbitaceous hosts. The whitefly population (Asia-I) reared in the glass house transmitted the virus to bottle gourd with 4 h of acquisition access period (AAP) and 24 h of inoculation feeding period (IFP). Heavy infestation of greenhouse whiteflies, Trialeurodes vaporariorum on infected chayote plant in Kodaikanal paved way to investigations on its role in vector transmission of ToLCNDV. The field population of T. vaporariorum was found to be viruliferous in PCR using virus specific primers. The greenhouse whitefly efficiently transmitted the virus with 4 h of AAP and 24 h IFP. Seed-borne nature of ToLCNDV was confirmed in PCR by using Roja's and ToLCNDV specific primers in different parts of the fruit viz., pericarp, mesocarp, seed coat, endosperm and embryo. This is the first report of seed transmissible nature of ToLCNDV, its implication in transboundary movement of the virus across several countries is discussed.


Assuntos
Begomovirus/isolamento & purificação , Cucurbita/virologia , Doenças das Plantas/virologia , Sementes/virologia , Animais , Begomovirus/genética , DNA Viral/genética , Variação Genética , Genoma Viral , Hemípteros/virologia , Filogenia , Reação em Cadeia da Polimerase , Recombinação Genética , Análise de Sequência de DNA
12.
Virol J ; 15(1): 134, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-30165872

RESUMO

BACKGROUND: Geminiviruses cause major losses to several economically important crops. Pedilanthus leaf curl virus (PeLCV) is a pathogenic geminivirus that appeared in the last decade and is continuously increasing its host range in Pakistan and India. This study reports the identification and characterization of PeLCV-Petunia from ornamental plants in Pakistan, as well as geographical, phylogenetic, and recombination analysis. METHODS: Viral genomes and associated satellites were amplified, cloned, and sequenced from Petunia atkinsiana plants showing typical geminivirus infection symptoms. Virus-satellite complex was analyzed for phylogenetic and recombination pattern. Infectious clones of isolated virus and satellite molecules were constructed using a partial dimer strategy. Infectivity analysis of PeLCV alone and in combination with Digera yellow vein betasatellite (DiYVB) was performed by Agrobacterium infiltration of Nicotiana benthamiana and Petunia atkinsiana plants with infectious clones. RESULTS: PeLCV, in association with DiYVB, was identified as the cause of leaf curl disease on P. atkinsiana plants. Sequence analysis showed that the isolated PeLCV is 96-98% identical to PeLCV from soybean, and DiYVB has 91% identity to a betasatellite identified from rose. Infectivity analysis of PeLCV alone and in combination with DiYVB, performed by Agrobacterium infiltration of infectious clones in N. benthamiana and P. atkinsiana plants, resulted in mild and severe disease symptoms 14 days after infiltration, respectively, demonstrating that these viruses are natural disease-causing agents. Southern blot hybridization indicated successful replication of the virus-betasatellite complex in the infected plants. Phylogenetic analysis suggests that PeLCV originated from Pakistan and later spread to India. Recombination analysis predicted that PeLCV is a donor parent for recombination and evolution of two important begomoviruses, Papaya leaf curl virus (PaLCuV) and Radish leaf curl virus (RaLCuV). The molecular phylogeny of genes encoding coat protein (CP) and replication associated protein (Rep) depict a complex evolutionary pattern of the viruses, with wide diversity in both of the genes. CONCLUSIONS: This study presents PeLCV and DiYVB as a new natural combination resulting in leaf curl disease on P. atkinsiana plants. Phylogenetic analysis, in addition to recent agricultural reports, identify PeLCV as an emerging broad host range Begomovirus that is resident in Pakistan and, more recently, has also spread to India. Recombination analysis showed that PeLCV was involved in a natural recombinational event leading to the evolution of two recombinant begomoviruses, RaLCuV and PaLCuV.


Assuntos
Begomovirus/classificação , Begomovirus/genética , Petunia/virologia , Filogeografia , Recombinação Genética , Vírus Satélites/genética , Begomovirus/isolamento & purificação , Southern Blotting , Paquistão , Doenças das Plantas/virologia , Análise de Sequência de DNA , Tabaco/virologia
13.
Curr Opin Virol ; 33: 167-176, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30243102

RESUMO

Emerging plant viruses are one of the greatest problems facing crop production worldwide, and have severe consequences in the developing world where subsistence farming is a major source of food production, and knowledge and resources for management are limited. In Africa, evolution of two viral disease complexes, cassava mosaic begomoviruses (CMBs) (Geminiviridae) and cassava brown streak viruses (CBSVs) (Potyviridae), have resulted in severe pandemics that continue to spread and threaten cassava production. Identification of genetically diverse and rapidly evolving CMBs and CBSVs, extensive genetic variation in the vector, Bemisia tabaci (Hemiptera: Aleyrodidae), and numerous secondary endosymbiont profiles that influence vector phenotypes suggest that complex local and regional vector-virus-plant-environment interactions may be driving the evolution and epidemiology of these viruses.


Assuntos
Begomovirus/crescimento & desenvolvimento , Hemípteros/virologia , Insetos Vetores/virologia , Manihot/crescimento & desenvolvimento , Doenças das Plantas/virologia , Potyviridae/crescimento & desenvolvimento , África , Animais , Begomovirus/isolamento & purificação , Países em Desenvolvimento , Potyviridae/isolamento & purificação
14.
Plant Dis ; 102(11): 2361-2370, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30252625

RESUMO

Virus diseases are among the main biotic factors constraining common bean (Phaseolus vulgaris L.) production in Tanzania. Disease management requires information on types, distribution, incidence, and genetic variation of the causal viruses, which is currently limited. Thus, a countrywide comprehensive survey was conducted. Use of a next-generation sequencing technique enabled simultaneous detection of 15 viruses belonging to 11 genera. De novo assembly resulted in many contigs, including complete or nearly complete sequences of Bean common mosaic virus (BCMV), Bean common mosaic necrosis virus (BCMNV), and Southern bean mosaic virus (SBMV). Some viruses (for example, SBMV and Tomato leaf curl Uganda virus-related begomovirus) were detected for the first time in common bean in Tanzania. Visually assessed virus-like disease incidence ranged from 0 to 98% but reverse-transcription polymerase chain reaction-based incidence of BCMV and BCMNV (7,756 samples) was mostly less than 40%. The Sanger-based nucleotide sequences encoding coat proteins of BCMV and BCMNV isolates were 90.2 to 100% and 97.1 to 100% identical to each other, respectively. Phylogenetic analysis showed that BCMV isolates were more diverse than BCMNV isolates. The information generated in this study will contribute to the development of molecular diagnostic tools and strategies for management of virus diseases nationally and internationally. [Formula: see text] Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .


Assuntos
Begomovirus/isolamento & purificação , Phaseolus/virologia , Doenças das Plantas/virologia , Vírus de Plantas/isolamento & purificação , Potyvirus/isolamento & purificação , Begomovirus/genética , Proteínas do Capsídeo/genética , Geografia , Patologia Molecular , Filogenia , Vírus de Plantas/genética , Potyvirus/genética , Análise de Sequência de DNA , Inquéritos e Questionários , Tanzânia
15.
Arch Virol ; 163(12): 3451-3453, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30178119

RESUMO

This is the first description of the complete genome sequence of a new monopartite begomovirus isolated from tomato with symptoms of tomato (yellow) leaf curl disease collected in the Seychelles. The DNA-A-like nucleotide sequences share the highest nucleotide sequence identity (84%) with tomato leaf curl Anjouan virus (ToLCAnjV) from the Comoros islands. Phylogenetic analysis confirmed its recombinant nature and its relationship to Old World monopartite and bipartite begomoviruses. This discovery of a new member of a species confirms the high genetic diversity of begomoviruses in the south-western Indian Ocean islands.


Assuntos
Begomovirus/isolamento & purificação , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Begomovirus/classificação , Begomovirus/genética , Genoma Viral , Fases de Leitura Aberta , Filogenia , Análise de Sequência de DNA , Seicheles
16.
Arch Virol ; 163(12): 3443-3446, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30145682

RESUMO

Two isolates of a novel monopartite begomovirus were obtained from naturally infected Ageratum conyzoides plants showing typical leaf curling and enation symptoms in Sichuan Province, China. The complete DNA sequences of two isolates were determined to be 2749 nucleotides in length. Sequence analysis showed that the two isolates shared 99.5% identity, and the highest identity (89.5-89.6%) was with the DNA sequence of tomato leaf curl Hainan virus (ToLCHaiV). No other begomoviruses or satellite molecules were detected in the two samples. Based on the species demarcation criterion for the genus Begomovirus established by the Geminiviridae Study Group, the virus is a novel monopartite begomovirus, and the tentative name "ageratum leaf curl Sichuan virus" (ALCScV) is proposed. Phylogenetic analysis showed that it clustered with ToLCHaiV, and recombination analysis showed that ALCScV might have arisen by recombination between viruses related to ToLCHaiV, ageratum leaf curl virus (ALCuV), and sida leaf curl virus (SiLCuV).


Assuntos
Ageratum/virologia , Begomovirus/genética , Begomovirus/isolamento & purificação , Doenças das Plantas/virologia , Sequência de Bases , Begomovirus/classificação , China , Genoma Viral , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Análise de Sequência de DNA
17.
Virus Res ; 256: 174-182, 2018 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-30149045

RESUMO

Spinach is a common vegetable crop and very little data is available about its virus infection. Symptomatic leaves of spinach were collected during field survey. Circular DNA molecules were amplified from symptomatic samples using rolling circle amplification (RCA). After restriction analysis, presumed bands of virus and satellites were cloned, sequenced and analyzed. Analysis of sequenced RCA product revealed the presence of chickpea chlorotic dwarf virus (CpCDV; Mastrevirus). Further analyses of the cloned virus showed that strain "C" of CpCDV was present in symptomatic samples of spinach collected from field associated with vein darkening, curling and enations on leaves. Amplification of alpha- and betasatellites with universal primers was performed. CpCDV showed association with cotton leaf curl Multan betasatellite (CLCuMB) and cotton leaf curl Multan alphasatellites (CLCuMA). Infectivity analysis of CpCDV and CpCDV/CLCuMB were done in N. benthamiana using particle bombardment method and the results showed that CpCDV was able to transreplicates CLCuMB in this host. To our knowledge, this is the first report of a dicot infecting mastrevirus (CpCDV) along with CLCuMB and CLCuMA associated with leaf curl disease of spinach in Pakistan. The significance of the results is discussed.


Assuntos
Begomovirus/isolamento & purificação , Geminiviridae/isolamento & purificação , Doenças das Plantas/virologia , Vírus Satélites/isolamento & purificação , Spinacia oleracea/virologia , Begomovirus/genética , DNA Viral/química , DNA Viral/genética , Geminiviridae/genética , Paquistão , Vírus Satélites/genética , Análise de Sequência de DNA , Tabaco/virologia
18.
Acta Virol ; 62(3): 246-258, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30160140

RESUMO

The samples from eggplants showing mixed symptoms of little leaf and mosaic were collected from two districts (Mirzapur and Varanasi) of Uttar Pradesh, India. The total nucleic acid extracted from these samples was amplified by PCR using universal 16S rRNA primers specific to phytoplasma and primers specific to DNA-A-like sequence of begomovirus. A total of eighteen eggplant samples showing the symptoms of little leaf and mosaic tested positive for the presence of both begomovirus and phytoplasma. The phytoplasma associated with the mixed symptoms of mosaic and little leaf in the eggplant samples was identified as a member belonging to Clover proliferation group (16SrVI) (nucleotide sequence identity of 97.5-97.8%). The characterized begomovirus from the eggplant samples was identified as a strain of previously described bipartite begomovirus tomato leaf curl Palampur virus (ToLCPalV) (92.5-94.1% nucleotide sequence identity), which is known to infect cucurbits and solanaceous crops in India and Ireland. Further, putative recombination events were detected within the 16S rRNA gene F2n/R2 fragment of phytoplasma and DNA-A of strain of ToLCPalV. Most of the sequence variations observed within the phytoplasma were due to intra and interspecific recombination events between eggplant little leaf-16SrVI-D, Ca. P. asteris-16SrI and Ca. P. pruni-16SrIII. Similarly, most of the DNA fragments of newly characterized strain of ToLCPalV appear to have been derived from tomato leaf curl New Delhi virus (ToLCNDV), squash leaf curl China virus (SLCCNV) and ToLCPalV like ancestors. This perhaps is the first evidence of mixed infection of both phytoplasma-begomovirus in eggplant in India.


Assuntos
Begomovirus/genética , Phytoplasma/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Solanum melongena/microbiologia , Begomovirus/isolamento & purificação , Begomovirus/fisiologia , Variação Genética , Índia , Filogenia , Phytoplasma/isolamento & purificação , Phytoplasma/fisiologia , Recombinação Genética , Análise de Sequência de DNA , Solanum melongena/virologia
19.
Arch Virol ; 163(11): 3199-3202, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30097742

RESUMO

A new begomovirus infecting Croton hirtus (Euphorbiaceae) from Colombia has been characterized. The complete DNA-A and DNA-B components were determined to be 2613 and 2551 nt in length, respectively, showing the typical genome organization of bipartite New World begomoviruses. DNA-A showed the highest nucleotide sequence identity (81.2%) to sida yellow mottle virus (JN411687), a begomovirus isolated from Sida rhombifolia in Cuba. Based on the current ICTV species demarcation criterion for the genus Begomovirus, we report a new member of this genus infecting C. hirtus. We propose that it be named Croton golden mosaic virus (CroGMV), based on the symptoms observed in the weed. Phylogenetic analysis revealed that CroGMV segregates into a single clade and has some relationship with viruses from Central America and the Caribbean. CroGMV is the first Croton-infecting bipartite begomovirus reported in the world.


Assuntos
Begomovirus/isolamento & purificação , Croton/virologia , Doenças das Plantas/virologia , Sequência de Bases , Begomovirus/classificação , Begomovirus/genética , Colômbia , Cuba , Genoma Viral , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
20.
PLoS One ; 13(8): e0202174, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30102735

RESUMO

Sweet potato is a vegetatively propagated crop that is produced for both growth in Korean fields and for export out of the country. The viruses that are present in introduced sweet potatoes can spread both domestically and to foreign countries. Determining the time and path of virus movement could help curtail its spread and prevent future dispersal of related viruses. Determining the consequences of past virus and sweet potato dispersal could provide insight into the ecological and economic risks associated with other sweet potato-infecting viral invasions. We therefore applied Bayesian phylogeographic inferences and recombination analyses of the available Sweepovirus sequences (including 25 Korean Sweepovirus genomes) and reconstructed a plausible history of Sweepovirus diversification and movement across the globe. The Mediterranean basin and Central America were found to be the launchpad of global Sweepovirus dispersal. Currently, China and Brazil are acting as convergence regions for Sweepoviruses. Recently reported Korean Sweepovirus isolates were introduced from China in a recent phase and the regions around China and Brazil continue to act as centers of Sweepovirus diversity and sites of ongoing Sweepovirus evolution. The evidence indicates that the region is an epidemiological hotspot, which suggests that novel Sweepovirus variants might be found.


Assuntos
Begomovirus/genética , Genoma Viral , Ipomoea batatas/virologia , Begomovirus/isolamento & purificação , Produção Agrícola , Filogenia , Filogeografia , Doenças das Plantas/genética , Recombinação Genética , República da Coreia , Análise Espacial
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