First Report of Yam mild mosaic virus in Yam in Guangxi Province, China

Yams (Dioscorea spp.) are widely grown in China as vegetables and herbal medicine. However, studies on viral diseases on yams are still limited. As a pilot project of a government initiative for improving yam productivity, a small study was conducted in Guangxi, a southern province of China, on viral disease in yams. Incidence of virus-like disease for the three extensively grown D. alata cultivars, GH2, GH5, and GH6, were 12 to 40%, 12 to 29%, and 11 to 25%, respectively, as found in a field survey with a five-plot sampling method in 2010. A total of 112 leaf samples showing mosaic or mottling or leaves without symptoms were collected from the cvs. GH2, GH5, GH6, and seven additional cultivars (D. alata cvs. GY2, GY23, GY47, GY69, GY62, GY72, and D. batatas cv. Tiegun). To determine if the symptoms were caused by Yam mild mosaic virus (YMMV; genus Potyvirus, family Potyviridae), total RNA was extracted from leaves with a commercial RNA purification kit (TIANGEN, Beijing, China), and reverse-transcription (RT)-PCR was conducted with a YMMV-specific primer pair (4) that amplifies the 3′-terminal portion of the viral genome. A PCR product with the predicted size of 262 bp was obtained from samples of GH5 (number testing positive of total number of leaves = 5 of 12), GH6 (24 of 42), and GY72 (1 of 1), but not from asymptomatic leaves. PCR products from a GH5 sample (YMMV-Nanning) and a GH6 sample (YMMV-Luzhai) were cloned and sequenced using an ABI PRISM 3770 DNA Sequencer. The two PCR products were 97% identical at nucleotide (nt) level and with the highest homology (89% identity) to a YMMV isolate (GenBank Accession No. AJ305466). To further characterize the isolates, degenerate primers (2) were used to amplify viral genome sequence corresponding to the C-terminal region of the nuclear inclusion protein b (NIb) and the N-terminal region of the coat protein (CP). These 781-nt fragments were sequenced and a new primer, YMMV For1 (5′-TTCATGTCGCACAAAGCAGTTAAG-3′) corresponding to the NIb region, was designed and used together with primer YMMV UTR 1R to amplify a fragment that covers the complete CP region of YMMV by RT-PCR. These 1,278-nt fragments were sequenced (GenBank Accession Nos. JF357962 and JF357963). CP nucleotide sequences of the YMMV-Nanning and YMMV-Luzhai isolates were 94% similar, while amino acid sequences were 99% similar. BLAST searches revealed a nucleotide identity of 82 to 89% and a similarity of 88 to 97% for amino acids to sequences of YMMV isolates (AF548499 and AF548519 and AAQ12304 and BAA82070, respectively) in GenBank. YMMV is known to be prevalent on D. alata in Africa and the South Pacific, and has recently been identified in the Caribbean (1) and Colombia (3). To our knowledge, this is the first report of the natural occurrence of YMMV in China and it may have implications for yam production and germplasm exchange within China. References: (1) M. Bousalem and S. Dallot. Plant Dis. 84:200, 2000. (2) D. Colinet et al. Phytopathology 84:65, 1994. (3) S. Dallot et al. Plant Dis. 85:803, 2001. (4) R. A. Mumford and S. E. Seal. J. Virol. Methods 69:73, 1997.

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First Report of Ranunculus mild mosaic virus on Ranunculus asiaticus in Yunnan Province, China

Plant Disease ◽

10.1094/pdis-92-11-1585a ◽

2008 ◽

Vol 92 (11) ◽

pp. 1585-1585 ◽

Cited By ~ 1

Author(s):

J. H. Wang ◽

S. Zhao ◽

X. M. Yang

Keyword(s):

Mosaic Virus ◽

Yunnan Province ◽

Disease Incidence ◽

Viral Disease ◽

Mild Mosaic ◽

Rt Pcr ◽

Potential Threat ◽

First Report ◽

Ranunculus Asiaticus ◽

Mild Mosaic Virus

In June 2007, a new viral disease occurred in commercial fields of Ranunculus asiaticus in the Yunnan Province of China. Infected plants exhibited mosaic symptoms and growth abnormalities. Viral disease incidence for this ornamental crop host in the Yunnan Province was estimated to range from 10 to 20%. Electron microscopic examination of negatively stained leaf-dip preparations from symptomatic plants identified long, flexuous linear particles (approximately 800 nm). The samples were tested using indirect antigen-coated plate (ACP)-ELISA. ACP-ELISA results showed that the leaf samples from symptomatic plants reacted positively to the potyvirus group antibody (Agdia Inc., Eklhart, IN). Total nucleic acid extracted from symptomatic plants was tested using reverse transcription (RT)-PCR with primers (S 5′-GGNAAAAYAGYGGNCARCC-3′; M4: 5′-GTTTTCCCAGTCACGAC-3′ [N = A, G, C, or T; Y = C or T; and R = A or G]) designed to amplify the 3′ terminal region of genomic RNA of the genus Potyvirus (1). RT-PCR produced a 1,650-bp amplification product that was cloned and sequenced (GenBank Accession No. EU684747). The sequenced portion showed 90 and 99% identity with the Ranunculus mild mosaic virus (RMMV) isolates (GenBank Accession Nos. DQ152191 and EF445546) from Italy and Israel, respectively (2). To our knowledge, this is the first report of RMMV in China. Infection from this virus may cause losses for cut-flower production of Ranunculus asiaticu and it is also a potential threat for international trade of Ranunculus germplasm. References: (1) J. Chen and J. P. Chen. Chin. J. Virol. 18:371, 2002. (2) M. Turina et al. Phytopathology 96:560, 2006.

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First Report of Olive mild mosaic virus and Sowbane mosaic virus in Spinach in Greece

Plant Disease ◽

10.1094/pdis-03-12-0273-pdn ◽

2012 ◽

Vol 96 (8) ◽

pp. 1230-1230 ◽

Cited By ~ 5

Author(s):

M. E. Gratsia ◽

P. E. Kyriakopoulou ◽

A. E. Voloudakis ◽

C. Fasseas ◽

I. E. Tzanetakis

Keyword(s):

Mosaic Virus ◽

Mild Mosaic ◽

Rt Pcr ◽

First Report ◽

Type Isolate ◽

Sequence Identity ◽

Leaf Deformation ◽

Mild Mosaic Virus ◽

Necrotic Spots ◽

Plant Pathol

Uncommon, viruslike symptoms (yellowing, line patterns, leaf deformation, and necrosis), were observed in spinach fields in the Marathon area, Greece in 2004. Seedlings from the same seed lot, grown in the greenhouse, also developed the same viruslike symptoms, indicating that the causal agent(s) of the disorder is seed-transmissible. Spinach seedlings of the same variety but a different lot and herbaceous indicators (Chenopodium quinoa, C. amaranticolor, Sonchus oleraceus, and Nicotiana benthamiana) were mechanically inoculated with infected material. Spinach developed yellowing or necrotic spots whereas indicators showed variety of symptoms including mosaic, vein banding, and necrotic lesions. Virus purifications, double-stranded RNA extractions, cloning, and sequencing (2,3) followed by a combination of molecular (reverse transcription [RT]-PCR and immunocapture RT-PCR) and serological (ELISA) techniques with antisera provided by Dr. Avgelis were performed as described (4), verifying the presence of two viruses in the diseased seedlings: Sowbane mosaic virus (SoMV), a sobemovirus, was present in spinach and indicators with mottling and leaf deformation, whereas Olive mild mosaic virus (OMMV), a necrovirus, was present in plants with necrotic spots. All RT-PCR products amplified with primers SoMV-F (5′-CAAATGGTCTTGGTCAGCAGTC)/SoMV-R (5′-GCATACGCTCGACGATCTG) and OMMV-F (5′-CAAACCCAGCCTGTGTTCGATG)/OMMV-R (5′-CATCAGTTTGGTAATCCATTGA) were sequenced and found to confirm the other results. The SoMV-spinach isolate polyprotein gene sequence (GenBank Accession No. DQ450973) has 95% sequence identity with the type isolate from C. quinoa (GenBank Accession No. GQ845002), whereas the OMMV-spinach isolate (GenBank Accession No. JQ288895) has 92% sequence identity with the OMMV type isolate from olive (GenBank Accession No. AY616760). SoMV has been found to naturally infect spinach in the Netherlands (1) and, to our knowledge, this is the first report on spinach in Greece. The presence of OMMV in spinach is, to our knowledge, the first report worldwide. Its natural host range is limited to olive, tulip, and now spinach. OMMV might be transmitted by Olpidium spp. and may, according to data of its close relatives, persist in the soil for several decades. Pollen- and seedborne viruses (PSVs) like sobemoviruses and necroviruses are of particular importance for a crop like spinach where crop increase takes place in small, seed production-designated areas. If a PSV spreads in such an area it has the potential to become a major problem for the industry, especially when it remains undetected. Infected seed can be shipped worldwide with PSVs, causing diseases and becoming endemic in areas where they were absent. For this reason and the fact that field losses can exceed 50%, rigorous monitoring for the presence of SoMV and OMMV in seed fields is essential to minimize the possibility of the viruses moving to new areas. References: (1) L. Bos and N. Huijberts. Eur. J. Plant Pathol. 102:707, 1996. (2) S. M. Girgis et al., Eur. J. Plant Pathol. 125:203, 2009, (3) I. E. Tzanetakis et al. J. Virol. Methods 124:73, 2005. (4) I. E. Tzanetakis et al. Virus Res. 121:199, 2006.

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First Report of Barley yellow mosaic virus in Barley in Spain

Plant Disease ◽

10.1094/pd-89-0105a ◽

2005 ◽

Vol 89 (1) ◽

pp. 105-105 ◽

Cited By ~ 3

Author(s):

M. A. Achon ◽

M. Marsiñach ◽

C. Ratti ◽

C. Rubies-Autonell

Keyword(s):

Mosaic Virus ◽

Yellow Mosaic Virus ◽

Complete Agreement ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

First Report ◽

Barley Yellow Mosaic Virus ◽

Pcr Products ◽

Mild Mosaic Virus ◽

Polymerase Chain

Recently, the presence of Barley mild mosaic virus (BaMMV) and the weakly serological detection of Barley yellow mosaic virus (BaYMV) were reported in Spain (1); both viruses are members of the genus Bymovirus (family Potyviridae). Random and symptomatic surveys were conducted during February and March of 2003 in barley fields in northeastern Spain to determine the occurrence of BaMMV and BaYMV. Leaves from 316 samples collected in 15 fields were analyzed using enzyme-linked immunosorbent assay (ELISA) with commercial antisera specific for BaYMV and BaMMV (Loewe Biochemica, Munich) as well as antisera against both viruses (provided by T. Klumen). Positive ELISA samples were further analyzed using reverse transcription-polymerase chain reaction (RT-PCR) with specific primers that amplify 445 bp of BaMMV and 433 bp of BaYMV (2). Complete agreement was observed between the ELISA and RT-PCR results. Mixed infections of BaYMV and BaMMV were detected in 10 samples, BaYMV in 5 samples and BaMMV in 3 samples. Samples positive for both viruses that exhibited clear mosaic symptoms were collected in two fields. RT-PCR products from five BaYMV-infected samples were cloned and sequenced and showed 96 to 98% identity to BaYMV isolates previously reported from Europe (Genbank Accession Nos. AJ1515479-85 and X95695-7) and 92 to 95% identity with isolates reported from Asia (GenBank Accession Nos. AB023585-96, AJ132268, AJ224619-22, AJ224624-28, AF536944-46, AF536948-58, D01091, D00544, and Z24677). Sequence identity of Spanish isolates were 96 to 99%. To our knowledge, this is the first report of BaYMV infecting barley in Spain and illustrates the association of both Bymoviruses infecting barley. References: (1) M. A. Achon et al. Plant Dis. 87:1004, 2003. (2) D. Hariri et al. Eur. J. Plant Pathol. 106:365, 2000.

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Detection of Banana mild mosaic virus and Banana virus X by polyvalent degenerate oligonucleotide RT-PCR (PDO-RT-PCR)

Journal of Virological Methods ◽

10.1016/j.jviromet.2007.01.004 ◽

2007 ◽

Vol 142 (1-2) ◽

pp. 41-49 ◽

Cited By ~ 10

Author(s):

Pierre-Yves Teycheney ◽

Isabelle Acina ◽

Benham E.L. Lockhart ◽

Thierry Candresse

Keyword(s):

Mosaic Virus ◽

Mild Mosaic ◽

Rt Pcr ◽

Degenerate Oligonucleotide ◽

Mild Mosaic Virus

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First Report of Tomato Brown Rugose Fruit Virus Infecting Tomato Crop in Saudi Arabia

Plant Disease ◽

10.1094/pdis-05-21-1065-pdn ◽

2021 ◽

Author(s):

Ahmed Sabra ◽

Mohammed Ali Al Saleh ◽

I. M. Alshahwan ◽

Mahmoud A. Amer

Keyword(s):

Saudi Arabia ◽

Mosaic Virus ◽

Solanum Lycopersicum ◽

Tomato Mosaic Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

First Report ◽

Pcr Products ◽

Dark Green ◽

Leaf Symptoms

Tomato (Solanum lycopersicum L.) is the most economically important member of family Solanaceae and cultivated worldwide and one of the most important crops in Saudi Arabia. The aim of this study is screening of the most common viruses in Riyadh region and identified the presence of tomato brown rugose fruit virus (ToBRFV) in Saudi Arabia. In January 2021, unusual fruit and leaf symptoms were observed in several greenhouses cultivating tomatoes commercially in Riyadh Region, Saudi Arabia. Fruit symptoms showed irregular brown spots, deformation, and yellowing spots which render the fruits non-marketable, while the leaf symptoms included mottling, mosaic with dark green wrinkled and narrowing. These plants presented the symptoms similar to those described in other studies (Salem et al., 2015, Luria et al., 2017). A total 45 Symptomatic leaf samples were collected and tested serologically against suspected important tomato viruses including: tomato chlorosis virus, tomato spotted wilt virus, tomato yellow leaf curl virus, tomato chlorotic spot virus, tomato aspermy virus, tomato bushy stunt virus, tomato black ring virus, tomato ringspot virus, tomato mosaic virus, pepino mosaic virus and ToBRFV using Enzyme linked immunosorbent assay (ELISA) test (LOEWE®, Biochemica, Germany), according to the manufacturers' instructions. The obtained results showed that 84.4% (38/45) of symptomatic tomato samples were infected with at least one of the detected viruses. The obtained results showed that 55.5% (25/45) of symptomatic tomato samples were found positive to ToBRFV, three out of 25 samples (12%) were singly infected, however 22 out of 45 (48.8%) had mixed infection between ToBRFV and with at least one of tested viruses. A sample with a single infection of ToBRFV was mechanically inoculated into different host range including: Chenopodium amaranticolor, C. quinoa, C. album, C. glaucum, Nicotiana glutinosa, N. benthamiana, N. tabacum, N. occidentalis, Gomphrena globosa, Datura stramonium, Solanum lycopersicum, S. nigrum, petunia hybrida and symptoms were observed weekly and the systemic presence of the ToBRFV was confirmed by RT-PCR and partial nucleotide sequence. A Total RNA was extracted from DAS-ELISA positive samples using Thermo Scientific GeneJET Plant RNA Purification Mini Kit. Reverse transcription-Polymerase chain reaction (RT-PCR) was carried out using specific primers F-3666 (5´-ATGGTACGAACGGCGGCAG-3´) and R-4718 (5´-CAATCCTTGATGTG TTTAGCAC-3´) which amplified a fragment of 1052 bp of Open Reading Frame (ORF) encoding the RNA-dependent RNA polymerase (RdRp). (Luria et al. 2017). RT-PCR products were analyzed using 1.5 % agarose gel electrophoresis. RT-PCR products were sequenced in both directions by Macrogen Inc. Seoul, South Korea. Partial nucleotide sequences obtained from selected samples were submitted to GenBank and assigned the following accession numbers: MZ130501, MZ130502, and MZ130503. BLAST analysis of Saudi isolates of ToBRFV showed that the sequence shared nucleotide identities ranged between 98.99 % to 99.50 % among them and 98.87-99.87 % identity with ToBRFV isolates from Palestine (MK881101 and MN013187), Turkey (MK888980, MT118666, MN065184, and MT107885), United Kingdom (MN182533), Egypt (MN882030 and MN882031), Jordan (KT383474), USA (MT002973), Mexico (MK273183 and MK273190), Canada (MN549395) and Netherlands (MN882017, MN882018, MN882042, MN882023, MN882024, and MN882045). To our knowledge, this is the first report of occurrence of ToBRFV infecting tomato in Saudi Arabia which suggests its likely introduction by commercial seeds from countries reported this virus and spread in greenhouses through mechanical means. The author(s) declare no conflict of interest. Keywords: Tomato brown rugose fruit virus, tomato, ELISA, RT-PCR, Saudi Arabia References: Luria N, et al., 2017. PLoS ONE 12(1): 1-19. Salem N, et al., 2015. Archives of Virology 161(2): 503-506. Fig. 1. Symptoms caused by ToBRFV showing irregular brown spots, deformation, yellowing spots on fruits (A, B, C) and bubbling and mottling, mosaic with dark green wrinkled and narrowing on leaf (D).

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Identification of Divergent Isolates of Banana Mild Mosaic Virus and Development of a New Diagnostic Primer to Improve Detection

Pathogens ◽

10.3390/pathogens9121045 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1045

Author(s):

Marwa Hanafi ◽

Rachid Tahzima ◽

Sofiene Ben Kaab ◽

Lucie Tamisier ◽

Nicolas Roux ◽

...

Keyword(s):

Mosaic Virus ◽

High Throughput Sequencing ◽

Plant Viruses ◽

Mild Mosaic ◽

Genome Variability ◽

Molecular Tests ◽

Pcr Products ◽

Reverse Primer ◽

Mild Mosaic Virus ◽

Germplasm Accessions

Banana mild mosaic virus (BanMMV) (Betaflexiviridae, Quinvirinae, unassigned species) is a filamentous virus belonging to the Betaflexiviridae family. It infects Musa spp. with a very wide geographic distribution. The genome variability of plant viruses, including the members of the Betaflexiviridae family, makes their molecular detection by specific primers particularly challenging. During routine indexing of the Musa germplasm accessions, a discrepancy was observed between electron microscopy and immunocapture (IC) reverse transcription (RT) polymerase chain reaction (PCR) test results for one asymptomatic accession. Filamentous viral particles were observed while molecular tests failed to amplify any fragment. The accession underwent high-throughput sequencing and two complete genomes of BanMMV with 75.3% of identity were assembled. Based on these sequences and on the 54 coat protein sequences available from GenBank, a new forward primer, named BanMMV CP9, compatible with Poty1, an oligodT reverse primer already used in diagnostics, was designed. A retrospective analysis of 110 different germplasm accessions from diverse origins was conducted, comparing BanMMCP2 and BanMMV CP9 primers. Of these 110 accessions, 16 tested positive with both BanMMCP2 and BanMMV CP9, 3 were positive with only BanMMCP2 and 2 tested positive with only BanMMV CP9. Otherwise, 89 were negative with the two primers and free of flexuous virions. Sanger sequencing was performed from purified PCR products in order to confirm the amplification of the BanMMV sequence for the five accessions with contrasting results. It is highly recommended to use the two primers successively to improve the inclusiveness of the protocol.

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Complete genome sequence of a novel zantedeschia mild mosaic virus isolate: the first report from Australia and from Alocasia sp.

Archives of Virology ◽

10.1007/s00705-015-2745-z ◽

2016 ◽

Vol 161 (4) ◽

pp. 1079-1082 ◽

Cited By ~ 3

Author(s):

Dawit B. Kidanemariam ◽

Adane D. Abraham ◽

Amit C. Sukal ◽

Timothy A. Holton ◽

James L. Dale ◽

...

Keyword(s):

Mosaic Virus ◽

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Virus Isolate ◽

Mild Mosaic ◽

First Report ◽

Mild Mosaic Virus

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First Report of Cucumber mosaic virus Subgroup IA Isolate Infecting Yucca aloifolia in Italy

Plant Disease ◽

10.1094/pdis-03-14-0324-pdn ◽

2014 ◽

Vol 98 (9) ◽

pp. 1284-1284 ◽

Cited By ~ 1

Author(s):

G. Parrella ◽

B. Greco

Keyword(s):

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Reverse Transcription ◽

Ornamental Plants ◽

Aphid Transmission ◽

Rt Pcr ◽

Cmv Infection ◽

Campania Region ◽

First Report ◽

Pcr Products

Yucca aloifolia L. (Spanish bayonet), family Asparagaceae, is the type species of the genus Yucca. It is native to Mexico and the West Indies and is appreciated worldwide as an ornamental plant. In 2013, during a survey for viruses in ornamental plants in the Campania region of southern Italy, symptoms consisting of bright chlorotic spots and ring spots 1 to 3 mm in diameter with some necrotic streaks were observed on leaves of two plants of Y. aloifolia growing in a nursery located in the Pignataro Maggiore municipality, Caserta Province. Cucumber mosaic virus (CMV) infection was suspected because the symptoms resembled those caused by CMV in Yucca flaccida (1). A range of herbal plant indicators was inoculated with sap extracts of symptomatic Y. aloifolia plants and developed symptoms indicative of CMV. Furthermore, 30 nm isometric virus particles were observed in the same Y. aloifolia sap extracts by transmission electron microscopy. The identity of the virus was confirmed by positive reaction in ELISA tests with CMV polyclonal antisera (Bioreba) conducted on sap extracts of symptomatic Y. aloifolia plants and systemically infected symptomatic hosts (i.e., Nicotiana tabacum, N. glutinosa, Cucumber sativus cv. Marketer, Solanum lycopersicum cv. San Marzano). The presence of CMV in the two naturally infected Y. aloifolia and other mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with the E.Z.N.A. Plant RNA Kit (Omega Bio-Tek), according to the manufacturer's instructions. RT-PCR was carried out with the ImProm-II Reverse Transcription System first-strand synthesis reaction (Promega) using the primer pair CMV1 and CMV2 (2). These primers amplify part of the CP gene and part of the 3′-noncoding region of CMV RNA3 and were designed to produce amplicons of different sizes to distinguish CMV isolates belonging to subgroups I or II (3). RT-PCR products were obtained from both naturally infected Y. aloifolia and mechanically inoculated plants as well as from PAE1 isolate of CMV (2), used as positive control, but not from healthy plants. Based on the length of the amplicons obtained (487 bp), the CMV isolate from Y. aloifolia (named YAL) belonged to subgroup I (3). The amplified RT-PCR products were purified with QIAquick PCR Purification Kit (Qiagen), cloned in the pGEMT vector (Promega), and three independent clones were sequenced at MWG (Ebersberg, Germany). Sequences obtained from the two CMV-infected Y. aloifolia plants were identical. This sequence was deposited at GenBank (Accession No. HG965199). Multiple alignments of the YAL sequence with sequences of other CMV isolates using MEGA5 software revealed highest percentage of identity (98.9%) with the isolates Z (AB369269) and SO (AF103992) from Korea and Japan, respectively. Moreover, the YAL isolate was identified as belonging to subgroup IA, based on the presence of only one HpaII restriction site in the 487-bp sequence, as previously proposed (2). Although CMV seems to not be a major threat currently for the production of Y. aloifolia, because the farming of this plant is performed using vegetative propagation, particular attention should be given to the presence of the virus in donor mother plants in order to avoid the dispersion of infected plants that could serve as sources for aphid transmission to other susceptible plant species. To our knowledge, this is the first report of CMV infection of Y. aloifolia in the world. References: (1) I. Bouwen et al. Neth. J. Plant Pathol. 84:175, 1978. (2) G. Parrella and D. Sorrentino. J. Phytopathol. 157:762, 2009. (3) Z. Singh et al. Plant Dis. 79:713, 1995.

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First Report and Molecular Characterization of Yam mild mosaic virus in Dioscorea alata on the Island of Martinique

Plant Disease ◽

10.1094/pdis.2000.84.2.200b ◽

2000 ◽

Vol 84 (2) ◽

pp. 200-200 ◽

Cited By ~ 7

Author(s):

M. Bousalem ◽

S. Dallot

Keyword(s):

Monoclonal Antibodies ◽

Mosaic Virus ◽

Papua New Guinea ◽

New Guinea ◽

Enzyme Linked Immunosorbent Assay ◽

Dioscorea Alata ◽

Mild Mosaic ◽

First Report ◽

Mild Mosaic Virus ◽

The Caribbean

Naturally infected Dioscorea alata plants showing mild mosaic were collected in 1998 on the island of Martinique in the Caribbean. Isolates were first screened by double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies raised against Yam mosaic virus (YMV) and antigen-coated plate ELISA with universal potyvirus monoclonal antibodies (Agdia, Elkhart, IN). A positive reaction was obtained only with the universal potyvirus antiserum. Immunocapture reverse-transcriptase polymerase chain reaction was performed for specific detection of Yam mild mosaic virus (YMMV [3]) and YMV. A product with the predicted size of 249 bp was obtained with YMMV primers. YMMV is a recently recognized distinct potyvirus infecting D. alata in West Africa and the South Pacific (2–4). It was originally described as Yam virus I and is synonymous with Dioscorea alata virus (4). To characterize the YMMV Martinique isolate, total RNA was extracted, and universal potyvirus degenerate primers (1) were used to amplify a 700-bp fragment that included the core and C-terminal region of the coat protein (CP) and 3′ untranslated region (3′UTR). Sequence information generated (EMBL AJ250336) from the cloned fragment was compared with sequences of other yam potyviruses. Sequence comparisons of the partial CP (453 nt) showed a similarity of 94.6% (amino acids [aa]) with the YMMV isolate from Papua New Guinea (EMBL AB022424 [2]); 72.2% (aa) with the Japanese yam mosaic virus (JYMV) isolate (EMBL AB016500); and 67 to 73% (aa) with 27 YMV isolates. These sequences are most diverse in the 3′UTR, which showed a similarity of 72.8% with the YMMV Papua New Guinea isolate, 30% with the JYMV isolate, and 26% with the YMV isolates. These results confirm, as previously shown by S. Fuji et al. (2), that YMMV should be classified as a new potyvirus of yam. This is the first report of the natural occurrence of YMMV in the Caribbean. References: (1) Colinet et al. Phytopathology 84:65, 1994. (2) S. Fuji et al. Arch Virol. 144:1415, 1999. (3) R. A. Munford and S. E. Seal. J. Virol. Methods 69:73, 1997. (4) B. O. Odu et al. Ann. Appl. Biol. 134:65, 1999.

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First Report of Apium virus Y on Cilantro, Celery, and Parsley in California

Plant Disease ◽

10.1094/pdis-92-8-1254b ◽

2008 ◽

Vol 92 (8) ◽

pp. 1254-1254 ◽

Cited By ~ 7

Author(s):

T. Tian ◽

H.-Y. Liu ◽

S. T. Koike

Keyword(s):

Mosaic Virus ◽

Consensus Sequence ◽

Amino Acid Sequences ◽

Apium Graveolens ◽

Petroselinum Crispum ◽

Rt Pcr ◽

First Report ◽

Virus Particles ◽

Pcr Products ◽

Reverse Primer

Recently, Apium virus Y (ApVY) was detected in field-grown cilantro (Coriandrum sativum), celery (Apium graveolens), and parsley (Petroselinum crispum) in California. In 2003, cilantro plants growing in three different fields in California (Monterey, San Joaquin, and San Luis Obispo counties) expressed symptoms of mosaic, vein clearing, and stunting. When plant sap was examined by transmission electron microscopy, flexuous, rod-shaped virus particles were observed. Total RNA was extracted from the symptomatic cilantro plants and used as a template in reverse transcription (RT)-PCR using universal potyvirus primers according to Chen et al. (1). The RT-PCR product was cloned into pGEM-T (Promega, Madison, WI) and the insert of 1,713 bp was sequenced (GenBank Accession No. EU515125). Nucleotide sequences from clones derived from three different infected cilantro plants were 89 to 97% identical to ApVY sequences encoding partial sequence of polyprotein in GenBank (Accession Nos. AY049716, EU127499, AF207594, AF203529, and EU255632). In 2007, celery plants showing necrotic line patterns and necrotic lesions on lower leaves and petioles were observed in several fields in two coastal counties in California (Monterey and Santa Clara counties). Flexuous, rod-shaped virus particles were also observed in the sap of those plants. ELISA for Cucumber mosaic virus and RT-PCR for Celery mosaic virus were negative. ApVY specific primers were designed on the basis of a consensus sequence of ApVY identified from cilantro in 2003; reverse primer 5′-GGCTCTTGCTATAGACAAATAGT-3′ and forward primer 5′-GAAGACCAAGCCAATGTGTGTA-3′. The sequence of RT-PCR products (GenBank Accession No. EU515126) amplified from infected celery had 90 to 98% nucleotide identity to ApVY. When the deduced amino acid sequences of NIb and CP regions from both cilantro and celery were used for comparison, they showed 95 to 99% identity with the known ApVY GenBank sequences mentioned above. More than 10 asymptomatic parsley plants growing in fields adjacent to the infected celery were also tested for ApVY and found to be infected. ApVY was previously identified in three Apiaceae weeds in Australia (2) and in celery in New Zealand (3). To our knowledge, this is the first report of ApVY on cilantro, celery, and parsley in California. References: (1) J. Chen et al. Arch. Virol. 146:757, 2001. (2) J. Moran et al. Arch. Virol. 147:1855, 2002. (3) J. Tang et al. Plant Dis. 91:1682, 2007.

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