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1.
Arch Virol ; 166(6): 1789-1793, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33811530

RESUMO

A previously undescribed monopartite begomovirus was identified in Kampot province, Cambodia, in Malvastrum coromandelianum plants exhibiting yellow vein symptoms characteristic of begomovirus infections. The apparently full-length viral component was cloned and sequenced following enrichment of circular DNA by rolling-circle amplification and restriction enzyme digestion. The genome of the virus was 2737 nucleotides in length (KP188831) and exhibited an organization like that of other monopartite begomoviruses, sharing the highest nucleotide sequence similarity (87.7% identity) with ageratum yellow vein virus (AM940137). A satellite molecule was amplified from total DNA by PCR amplification, using the betasatellite-specific primer pair ß01/ß02. The satellite molecule (1346 nt, KP188832) had structural characteristics like those of other betasatellites associated with begomoviruses and shared the highest nucleotide sequence similarity (84.8% identity) with malvastrum yellow vein betasatellite (MN205547). According to the criteria established for species demarcation for classification of begomoviruses (family Geminiviridae) and betasatellites (family Tolecusatellitidae), respectively, the virus isolate from M. coromandelianum in Cambodia is a previously undescribed novel monopartite begomovirus, for which the name "malvastrum yellow vein Cambodia virus" (MaYVCV) is proposed, and the betasatellite is a previously undescribed novel betasatellite, for which the name "malvastrum yellow vein Cambodia betasatellite" (MaYVKHB) is proposed.


Assuntos
Begomovirus/genética , DNA Satélite/genética , Malvaceae/virologia , Begomovirus/isolamento & purificação , Camboja , Filogenia , Doenças das Plantas/virologia
2.
Arch Virol ; 166(6): 1759-1762, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33745066

RESUMO

The whole genome sequence of a begomovirus (family Geminiviridae) infecting Muntingia calabura L. (family Muntingiaceae) from the province of Guayas in Ecuador was determined in this work. The major symptom observed on this plant species was yellow spots on leaves. The nucleotide sequences of three DNA-A clones and one DNA-B clone were compared to those of other begomoviruses. The DNA-A clones displayed the highest similarity to isolates of pepper leafroll virus (PepLRV), with 87.4 to 88.1% sequence identity. Likewise, the DNA-B clone showed the highest similarity (79.3-79.6% sequence identity) to PepLRV isolates. According to the demarcation criteria for begomovirus species, the begomovirus described in this work, for which we propose the name "muntingia yellow spot virus", represents a novel species. To our best knowledge, this is the first report of a begomovirus infecting a plant of the family Muntingiaceae.


Assuntos
Begomovirus/genética , Doenças das Plantas/virologia , Plantas/virologia , Begomovirus/isolamento & purificação , DNA Viral/genética , Equador , Phyllachorales
3.
Mol Biol Rep ; 48(2): 1383-1391, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33599950

RESUMO

Yellow vein mosaic disease is the major biotic constraint of okra cultivation in Sri Lanka. Identification and detailed molecular characterization of associated pathogen is needed for effective disease management. The genome of the begomovirus and betasatellite were amplified in symptomatic plant samples using specific degenerate primers. DNA-A genome of twelve isolates representing different locations in Sri Lanka were cloned, sequenced and deposited in GenBank database (Accession No- KX698087- KX698092 and MH455207- MH455212). Size of the complete nucleotide sequences ranged from 2735 to 2786 bp. The genome organization showed characteristics of begomoviruses. The pairwise sequence identity revealed the association of two different begomovirus species. Five of the isolates showed > 91% of sequences identity with Bhendi yellow vein mosaic virus, and the rest of the seven isolates were around 92% of identity with Okra enation leaf curl virus. This is further supported by phylogenetic analysis where both of these group of isolates were in different cluster. Recombination analysis showed the presence of recombinant fragments in the virus isolates associated with okra yellow vein mosaic disease (OYVMD) in Sri Lanka. Attempts to amplify DNA- B were failed in any of the samples tested. However, both type of the begomovirus species associated with betasatellite species, Bhendi yellow vein mosaic betasatellite. The present study has revealed the association of two distinct monopartite begomovirus species, Bhendi yellow vein mosaic virus or Okra enation leaf curl virus, with OYVMD in Sri Lanka.


Assuntos
Abelmoschus/virologia , Begomovirus/genética , Doenças das Plantas/virologia , Abelmoschus/genética , Begomovirus/isolamento & purificação , Begomovirus/patogenicidade , Análise por Conglomerados , DNA Viral/genética , DNA Viral/isolamento & purificação , Variação Genética/genética , Genoma Viral/genética , Filogenia , Doenças das Plantas/genética , Análise de Sequência de DNA , Software
4.
Mol Biol Rep ; 48(3): 2143-2152, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33635470

RESUMO

Geminiviridae comprises the largest family of plant viruses which causes severe crop losses in India. The highest pungency chilli Bhut-Jolokia or ghost pepper (Capsicum chinense Jaqc.) hails from North-East region of India and is used in many dishes to add flavors and also for its medicinal value. However, this chilli variety is also affected by viruses leading to crop and economic losses. The present study reports the identification of begomoviruses in the infected chilli Bhut-Jolokia leaf samples collected from eight different places of North-East region (Manipur) of India. The infected leaf samples were screened for the presence of viral genome by rolling circle amplification (RCA) followed by PCR using degenerate primer pairs. The subsequent analyses using restriction fragment length polymorphism and sequencing revealed the presence of Cotton leaf curl Multan virus (CLCuMuV), and Tomato leaf curl Patna betasatellite (ToLCPaB). The findings focus on the phylogenetic relatedness, probable recombinational hot-spots and evolutionary divergence of the viral DNA sequences with the current reported begomoviral genome. To the best of our knowledge, this is the first report showing the presence of CLCuMuV, and associated non-cognate ToLCPaB with leaf curl disease of Bhut-Jolokia chillies. The study reveals potential recombination sites on both viral genome and betsatellite which, during the course of evolution, may have aided the virus to progress and successfully establish infection in chilli plants. Taken together, our results suggest a possible spread of CLCuMuV to the hitherto non-host crop in the North-East region of India.


Assuntos
Begomovirus/fisiologia , Capsicum/virologia , Doenças das Plantas/virologia , Vírus Satélites/fisiologia , Composição de Bases/genética , Begomovirus/genética , Begomovirus/isolamento & purificação , DNA Satélite/genética , DNA Viral/genética , Evolução Molecular , Genoma Viral , Geografia , Índia , Filogenia , Recombinação Genética/genética
5.
Arch Virol ; 165(9): 2099-2103, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32556597

RESUMO

Geminiviruses cause considerable yield loss in several crop plants worldwide. In 2016, several hollyhock plants displaying yellow mosaic and leaf curling symptoms were noticed in a nursery of Jawaharlal Nehru University, New Delhi, India. Analysis of the collected samples indicated an association of monopartite and bipartite begomoviruses with satellites. Three begomoviruses (including a member of a new begomovirus species), two alphasatellites, and a betasatellite were isolated from yellow-mosaic-disease-affected plants. Similarly, a begomovirus, two alphasatellites, and a betasatellite were found to be associated with leaf curl disease of hollyhock. These begomoviruses and satellites were found to be recombinants. By harboring diverse begomoviruses and satellite DNAs, hollyhock may serve as a potential source of virus inoculum.


Assuntos
Begomovirus/isolamento & purificação , Malvaceae/virologia , Doenças das Plantas/virologia , Vírus Satélites/isolamento & purificação , Begomovirus/classificação , Begomovirus/genética , Begomovirus/fisiologia , Índia , Filogenia , Vírus Satélites/classificação , Vírus Satélites/genética , Vírus Satélites/fisiologia
6.
Arch Virol ; 165(7): 1659-1665, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32405827

RESUMO

In this work, a begomovirus isolated from a bean plant coinfected with the potyviruses bean common mosaic virus and bean common mosaic necrosis virus was characterized. The three viruses were detected by high-throughput sequencing and assembly of total small RNAs, but the begomovirus-related contigs did not allow precise identification. Molecular analysis based on standard DNA amplification techniques revealed the presence of a single bipartite virus, which is a novel begomovirus according to the current taxonomic criteria. Infectious clones were generated and agroinoculated into Phaseolus vulgaris and Nicotiana benthamiana plants. In all cases, viral DNA-A and DNA-B were detected in new growths, but no symptoms were observed, thus indicating that this virus produces asymptomatic infections in both host species.


Assuntos
Begomovirus/isolamento & purificação , Phaseolus/virologia , Doenças das Plantas/virologia , Potyvirus/fisiologia , Tabaco/virologia , Begomovirus/classificação , Begomovirus/genética , Begomovirus/fisiologia , Coinfecção/virologia
7.
Bull Entomol Res ; 110(4): 487-496, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31987066

RESUMO

The whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most important agricultural pests and virus vectors worldwide. Bemisia tabaci is considered a complex of cryptic species with at least 44 species. Among them, the species Middle East-Asia Minor 1 (MEAM1, formerly B biotype) and Mediterranean (MED, formerly Q biotype) are the most important, and they have attained global status. In Brazil, MEAM1 was first reported in the 1990s and is currently the predominant species in the country, meanwhile, MED was recently reported in the South and Southeast regions and was found to be mainly associated with ornamental plants. Currently, an increasing problem in the management of whitefly infestations in greenhouses associated with bell pepper was observed in São Paulo State, Brazil. The whiteflies were collected and identified based on a microsatellite locus (primer pair BEM23F and BEM23R) and the mitochondrial cytochrome oxidase I gene followed by restriction fragment length polymorphism analysis and sequencing. We observed that MED was the predominant species collected on bell pepper, but it was also found on tomato, cucumber, eggplant, and weeds grown in greenhouses. In open field, we found MED on tomatoes, bell peppers, and eggplants. In addition, MED was identified in Goiás State in association with ornamental plants. The begomovirus Tomato severe rugose virus and the crinivirus Tomato chlorosis virus was detected on bell pepper and tomato, respectively. Only MED specimens were found associated with the virus-infected plants. Moreover, we also investigated the endosymbionts present in the MED whiteflies. The collected populations of B. tabaci MED harbored a diversity of secondary endosymbionts, with Hamiltonella (H) found predominantly in 89 specimens of the 129 tested. These results represent a new concern for Brazilian agriculture, especially for the management of the newly introduced whitefly MED species, which must be implemented to limit the spreading and establishment of this pest in different crops in this country.


Assuntos
Produtos Agrícolas , Hemípteros/classificação , Hemípteros/virologia , Animais , Begomovirus/isolamento & purificação , Brasil , Crinivirus/isolamento & purificação , Surtos de Doenças , Hemípteros/genética , Espécies Introduzidas , Repetições de Microssatélites , Doenças das Plantas/virologia , Simbiose , Verduras
8.
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
9.
Virus Genes ; 56(1): 16-26, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31773493

RESUMO

Betasatellites are a group of circular, single-stranded DNA molecules that are frequently found to be associated with monopartite begomoviruses of the family Geminiviridae. Betasatellites require their helper viruses for replication, movement, and encapsidation and they are often essential for induction of typical disease symptoms. The ßC1 protein encoded by betasatellites is multifunctional that participates in diverse cellular events. It interferes with several cellular processes like normal development, chloroplasts, and innate immune system of plants. Recent research has indicated ßC1 protein interaction with cellular proteins and its involvement in modulation of the host's cell cycle and symptom determination. This article focuses on the functional mechanisms of ßC1 and its interactions with other viral and host proteins.


Assuntos
Begomovirus/fisiologia , Doenças das Plantas/virologia , Vírus Satélites/fisiologia , Begomovirus/classificação , Begomovirus/genética , Begomovirus/isolamento & purificação , DNA Satélite/genética , DNA Satélite/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Vírus Satélites/genética , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral
10.
Virol J ; 16(1): 131, 2019 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-31706358

RESUMO

BACKGROUND: In Oman tobacco (Nicotiana tabacum; family Solanaceae) is a minor crop, which is produced only for local consumption. In 2015, tobacco plants exhibiting severe downward leaf curling, leaf thickening, vein swelling, yellowing and stunting were identified in fields of tobacco in Suhar Al-Batina region, Oman. These symptoms are suggestive of begomovirus (genus Begomovirus, family Geminiviridae) infection. METHODS: Circular DNA molecules were amplified from total DNA extracted from tobacco plants by rolling circle amplification (RCA). Viral genomes were cloned from RCA products by restriction digestion and betasatellites were cloned by PCR amplification from RCA product, using universal primers. The sequences of full-length clones were obtained by Sanger sequencing and primer walking. Constructs for the infectivity of virus and betasatellite were produced and introduced into plants by Agrobacterium-mediated inoculation. RESULTS: The full-length sequences of 3 begomovirus and 3 betasatellite clones, isolated from 3 plants, were obtained. Analysis of the full-length sequences determined showed the virus to be a variant of Chilli leaf curl virus (ChiLCV) and the betasatellite to be a variant of Tomato leaf curl betasatellite (ToLCB). Both the virus and the betasatellite isolated from tobacco show the greatest levels of sequence identity to isolates of ChiLCV and ToLCB identified in other hosts in Oman. Additionally clones of ChiLCV and ToLCB were shown, by Agrobacterium-mediated inoculation, to be infectious to 3 Nicotiana species, including N. tabacum. In N. benthamiana the betasatellite was shown to change the upward leaf rolling symptoms to a severe downward leaf curl, as is typical for many monopartite begomoviruses with betasatellites. CONCLUSIONS: The leaf curl disease of tobacco in Oman was shown to be caused by ChiLCV and ToLCB. This is the first identification of ChiLCV with ToLCB infecting tobacco. The study shows that, despite the low diversity of begomoviruses and betasatellites in Oman, the extant viruses/betasatellites are able to fill the niches that present themselves.


Assuntos
Begomovirus/isolamento & purificação , Capsicum/virologia , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Vírus Satélites/isolamento & purificação , Tabaco/virologia , Begomovirus/classificação , Begomovirus/genética , Begomovirus/patogenicidade , DNA Viral/genética , Genoma Viral/genética , Omã , Filogenia , Folhas de Planta/virologia , Vírus Satélites/classificação , Vírus Satélites/genética , Vírus Satélites/patogenicidade , Análise de Sequência de DNA
11.
Biomol Concepts ; 10(1): 184-193, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31743101

RESUMO

This study was conducted to determine the incidence, diversity and distribution of viruses infecting pepper (Capsicum spp.) in the central, northern and northeastern parts of Thailand. During a survey in 2016 - 2019, a total of 2,149 leaf samples from symptomatic and asymptomatic peppers were collected randomly from farmer's fields, and preliminary tested by an enzyme-linked immunosorbent assay (ELISA) using 7 antibodies specific for cucumber mosaic virus (CMV), chilli veinal mottle virus (ChiVMV), tomato necrotic ringspot virus (TNRV), tobacco mosaic virus (TMV), potato virus Y (PVY), tomato spotted wilt virus (TSWV), and begomoviruses. Our data revealed that the incidence of the viruses infecting pepper in Thailand was high, accounting for nearly 70% (1,482 infected samples). The highest viral incidence was found in the central part (96%), followed by the north (74.4%) and the northeastern (52.8%), respectively. Begomoviruses, CMV, ChiVMV, and TNRV were detected in the samples at varying rates, whereas PVY, TMV, and TSWV were not detected. Of these, the most frequently found virus was Begomoviruses accounting for nearly 33%, with the highest rate (ca. 82%) in the central Provinces of Thailand. In addition, of the 1,482 infected samples, mixed infections among the four viruses were also found in 616 samples (ca. 42%), and CMV + ChiVMV (approximately 11%) was the most common mixed infection. This is the first report describing an occurrence of viruses in pepper of Thailand, and the results obtained have revealed that viruses infecting pepper are widespread, which may pose a threat to pepper production in Thailand.


Assuntos
Begomovirus/isolamento & purificação , Capsicum/virologia , Doenças das Plantas/estatística & dados numéricos , Doenças das Plantas/virologia , Begomovirus/genética , Capsicum/genética , DNA de Plantas/genética , DNA de Plantas/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Humanos , Tailândia
12.
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
13.
Viruses ; 11(7)2019 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261973

RESUMO

Plant DNA viruses of the genus Begomovirus have been documented as the most genetically diverse in the family Geminiviridae and present a serious threat for global horticultural production, especially considering climate change. It is important to characterize naturally existing begomoviruses, since viral genetic diversity in non-cultivated plants could lead to future disease epidemics in crops. In this study, high-throughput sequencing (HTS) was employed to determine viral diversity of samples collected in a survey performed during 2012-2016 in seven states of Northern-Pacific Mexico, areas of diverse climatic conditions where different vegetable crops are subject to intensive farming. In total, 132 plant species, belonging to 34 families, were identified and sampled in the natural ecosystems surrounding cultivated areas (agro-ecological interface). HTS analysis and subsequent de novo assembly revealed a number of geminivirus-related DNA signatures with 80 to 100% DNA similarity with begomoviral sequences present in the genome databank. The analysis revealed DNA signatures corresponding to 52 crop-infecting and 35 non-cultivated-infecting geminiviruses that, interestingly, were present in different plant species. Such an analysis deepens our knowledge of geminiviral diversity and could help detecting emerging viruses affecting crops in different agro-climatic regions.


Assuntos
Begomovirus/isolamento & purificação , Biodiversidade , Produtos Agrícolas/virologia , Doenças das Plantas/virologia , Vírus de Plantas/isolamento & purificação , Begomovirus/classificação , Begomovirus/genética , Produtos Agrícolas/crescimento & desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , México , Filogenia , Vírus de Plantas/classificação , Vírus de Plantas/genética
14.
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
15.
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
16.
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
17.
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
18.
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
19.
J Virol Methods ; 267: 1-7, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30771384

RESUMO

Current techniques for plant virus detection, such as RT- PCR and ELISA, require multistep procedures and rely on sophisticated equipment. Due to the global spread of plant viruses, the development of simpler, faster and cheaper assay methods is inevitable. Gold nanoparticles (AuNPs) had raised much interest during recent years due to their novel optical properties or diagnostic purposes. The localized surface plasmon resonance (LSPR1) of AuNPs had been used in the development of novel colorimetric nano-biosensing systems. The frequency and intensity of the LSPR peak generally depend on the shape, size and the surrounding medium of the AuNPs. In this study, unmodified AuNPs had been used to detect the unamplified Tomato yellow leaf curl virus (TYLCV) genome in infected plants. A specific DNA probe complementary to the coat protein region of virus genome was designed. The extracted total DNA of uninfected and infected plants was mixed with hybridization buffer and the designed probe. The mixture was denatured, annealed and then cooled to room temperature and was followed by AuNPs addition. The color changes in the samples indicating the presence of target virus infections were assessed visually after the addition of salt and confirmed by UV-Vis spectroscopy. The results showed that this strategy allowed for fast and sensitive detection of TYLCV genome and eliminated the need for PCR amplification and detection equipment.


Assuntos
Begomovirus/isolamento & purificação , Técnicas Biossensoriais , Genoma Viral , Nanopartículas Metálicas , Ressonância de Plasmônio de Superfície , Begomovirus/genética , Colorimetria/métodos , Sondas de DNA , Ouro , Lycopersicon esculentum/virologia , Nanotecnologia/métodos , Doenças das Plantas/virologia
20.
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
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