First Report of Cichorium endivia (Asteraceae) as a Natural Host of Groundnut ringspot orthotospovirus in Brazil.

Endive (Cichorium endivia L.) is a very important cash crop for small farmers in Brazil. During inspections conducted in the summer season of 2019–2020, leaf samples of C. endivia ‘La Spezia’ seedlings exhibiting typical symptoms of orthotospoviruses infection (viz. concentric chlorotic spots and apical leaf deformation; ≈ 10%) were collected in commercial greenhouses in Brasília–DF, Central Brazil. Leaves of one healthy and three symptomatic plants were initially evaluated via double antibody sandwich enzyme-linked immunosorbent assay (DAS–ELISA) with polyclonal antibodies (produced at CNPH) raised against the nucleoprotein of the three major orthotospoviruses: tomato spotted wilt orthotospovirus (TSWV), groundnut ringspot orthotospovirus (GRSV) and tomato chlorotic spot orthotospovirus (TCSV). Strong serological reactions were observed only against GRSV antibodies exclusively in extracts from symptomatic samples. In order to confirm the causal agent of those symptoms, total RNA was extracted (Trizol®; Sigma) from infected leaf samples and used in a two-step reverse transcriptase polymerase chain reaction (RT–PCR) approach. Synthesis of the cDNA was carried out with the J13 primer (5’–CCC GGA TCC AGA GCA AT–3’) (Cortez et al., 2001) followed by PCR assays with the primer pair BR60 (5’–AGA GCA ATC GTG TCA–3`) and BR65 (5’–ATC AAG CCT TCT GAA AGT CAT–3’) (Eiras et al., 2001). This primer set amplifies a fragment of 453 bp including the untranslated region at the 3’ terminus of the small RNA and the protein N–coding gene of at least five orthotospoviruses: TSWV, GRSV, TCSV, chrysanthemum stem necrosis orthotospovirus (CSNV) and zucchini lethal chlorosis orthotospovirus (ZLCV) (Eiras et al., 2001). The obtained amplicons (≈ 432 bp) were subsequently subjected to Sanger dideoxy nucleotide sequencing at CNPH. BLASTn analysis showed >99% identity with a wide array of GRSV isolates available in the GenBank. The nucleotide sequence of Tospo #1 (MT215222) and Tospo #3 (MT215224) isolates displayed 100% identity between them, whereas the Tospo #2 (MT215223) isolate displayed one non–synonymous point mutation in the 3’ untranslated region in comparison with the former two isolates. Three plants of C. endivia, Capsicum annuum L. cv. Ikeda, tomato (Solanum lycopersicum L.) cv. Santa Clara and its isoline ‘LAM–147’ (with the Sw–5 resistance gene), Nicotiana rustica L., Lactuca sativa L. (‘Vanda’ and ‘PI-342444’) and Gomphrena globosa L. were mechanically inoculated individually with each GRSV isolate in order to confirm their pathogenicity. Chlorotic lesions and mosaic were observed seven days after inoculation of all plant materials, except the tomato inbred line ‘LAM–147’, which has the Sw-5 gene that confers broad–spectrum resistance to all Brazilian orthotospoviruses (Boiteux and Giordano, 1993). The GRSV infection was confirmed via DAS–ELISA and RT–PCR 15 days after inoculation, using the same set of antibodies and the primer pair BR60 / BR65. Transmission electron microscopy of ultrathin sections from symptomatic leaf tissues, both from field–infected and experimentally inoculated endive revealed the presence of typical orthotospovirus particles, within endoplasmic reticulum cisternae. Natural infection of endive by TSWV has been reported in Greece (Chatzivassiliou et al., 2000) and by TCSV in São Paulo State, Brazil and in Florida, USA (Subramanya Sastry et al., 2019). To our knowledge, it is the first report of GRSV naturally infecting this Asteraceae species in Brazil. Confirmation of GRSV infection of C. endivia plants is a relevant piece of information aiming to design effective disease management strategies. References: Boiteux, L.S. and Giordano, L. B. 1993. Euphytica 71: 151. Eiras, M. et al. 2001. Fitopatol. Bras. 26: 170. Chatzivassiliou, E.K. et al. 2000 Ann. Appl. Biol. 137: 127. Cortez, I., et al. 2001. Arch. Virol. 146: 265. Subramanya Sastry, K., et al. 2019. Encyclopedia of plant viruses and viroids. Springer, New Delhi. https://doi.org/10.1007/978-81-322-3912-3.

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First Report of Cucurbit aphid-borne yellows virus in Iran Causing Yellows on Four Cucurbit Crops

Plant Disease ◽

10.1094/pd-90-0526a ◽

2006 ◽

Vol 90 (4) ◽

pp. 526-526 ◽

Cited By ~ 7

Author(s):

K. Bananej ◽

C. Desbiez ◽

C. Wipf-Scheibel ◽

I. Vahdat ◽

A. Kheyr-Pour ◽

...

Keyword(s):

Citrullus Lanatus ◽

Healthy Plant ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

First Report ◽

Chain Reactions ◽

Reference Isolate ◽

Sigma Chemical ◽

International Mycological Institute ◽

Das Elisa

A survey was conducted from 2001 to 2004 in the major cucurbit-growing areas in Iran to reassess the relative incidence of cucurbit viruses. Severe yellowing symptoms were observed frequently on older leaves of cucurbit plants in various regions in outdoor crops, suggesting the presence of Cucurbit aphid-borne yellows virus (CABYV, genus Polerovirus, family Luteoviridae) (1,2). Leaf samples (n = 1019) were collected from plants of melon (Cucumis melo L.), cucumber (C. sativus L.), squash (Cucurbita sp.), and watermelon (Citrullus lanatus L.) showing various virus-like symptoms (mosaic, leaf deformation, yellowing). All samples, collected from 15 provinces, were screened for the presence of CABYV by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with IgGs and alkaline phosphatase-conjugated IgGs against a CABYV reference isolate (1). Of the 1,019 samples tested, 471 were positive for CABYV using DAS-ELISA. Some of the positive samples had typical severe yellowing symptoms while symptoms in other samples were masked by mosaic or leaf deformations caused by other viruses frequently found in mixed infections (data not shown). During the entire survey, CABYV was detected by DAS-ELISA in 201 of 503 melon samples, 72 of 129 cucumber samples, 158 of 249 squash samples, and 40 of 138 watermelon samples. These results indicate that CABYV is widely distributed on four cucurbit species in the major growing areas of Iran. In order to confirm CABYV identification, total RNA extracts (TRI-Reagent, Sigma Chemical, St Louis, MO) were obtained from 25 samples that were positive using DAS-ELISA originating from Khorasan (n = 4), Esfahan (n = 6), Teheran (n = 3), Hormozgan (n = 4), Azerbaiejan-E-Sharqi (n = 4), and Kerman (n = 4). Reverse transcription-polymerase chain reactions (RT-PCR) were carried out using forward (5′-CGCGTGGTTGTGG-TCAACCC-3′) and reverse (5′-CCYGCAACCGAGGAAGATCC-3′) primers designed in conserved regions of the coat protein gene according to the sequence of a CABYV reference isolate (3) and three other unpublished CABYV sequences. RT-PCR experiments yielded an expected 479-bp product similar to the fragment amplified with extracts from the reference isolate. No amplification of the product occurred from healthy plant extracts. To our knowledge, this is the first report of the occurrence of CABYV in Iran on various cucurbit species. The high frequency (46.2%) with which CABYV was detected in the samples assayed indicates that this virus is one of the most common virus infecting cucurbits in Iran. References: (1) H. Lecoq et al. Plant Pathol. 41:749, 1992 (2) M. A. Mayo and C. J. D'Arcy. Page 15 in: The Luteoviridae. H. G. Smith and H. Barker, eds. CAB International Mycological Institute, Wallingford, UK, 1999. (3) H. Guilley et al. Virology 202:1012, 1994.

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First Report of Sharka Disease Caused by Plum Pox Virus in Lithuania

Plant Disease ◽

10.1094/pdis.1998.82.12.1405c ◽

1998 ◽

Vol 82 (12) ◽

pp. 1405-1405 ◽

Cited By ~ 1

Author(s):

J. Staniulis ◽

J. Stankiene ◽

K. Sasnauskas ◽

A. Dargeviciute

Keyword(s):

Coat Protein ◽

Plant Protection ◽

Virus Disease ◽

Pcr Amplification ◽

Enzyme Linked Immunosorbent Assay ◽

Plum Pox Virus ◽

Rt Pcr ◽

First Report ◽

Das Elisa ◽

Sharka Disease

Plum pox (sharka) disease caused by plum pox potyvirus (PPV) is considered the most important virus disease of stone fruit trees in Europe and the Mediterranean region. Nearly all those countries that produce stone fruits are affected (3). The causal virus of the disease is a European Plant Protection Organization A2 quarantine pathogen. Symptoms of leaf mottling, diffuse chlorotic spots, rings, and vein banding of varied intensity characteristic for plum pox virus infection were observed in the plum (Prunus domestica) orchard tree collection of the Lithuanian Institute of Horticulture in Babtai in 1996. Presence of this virus in the diseased trees was confirmed by double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) with kits from BIOREBA (Reinach, Switzerland) and by polyclonal antibodies raised against a Moldavian isolate of PPV courtesy of T. D. Verderevskaya (Institute of Horticulture, Kishinev, Moldova). ELISAs with both sources of antiserum were positive for presence of PPV. Electron microscopy revealed the presence of potyvirus-like particles averaging 770 nm in extracts of mechanically inoculated plants of Chenopodium foetidum (chlorotic LL [local lesions]) and Pisum sativum cvs. Rainiai and Citron (mottling). For molecular diagnosis and characterization of this isolate, PPV-971, reverse transcription-polymerase chain reaction (RT-PCR) was employed. Total RNA from the leaves of infected pea was isolated as described (2). High molecular weight RNA selectively precipitated with 2 M lithium chloride was used for RT-PCR amplification of the coat protein encoding sequence by use of specific primers complementary to 5′ and 3′ parts of PPV coat protein L1 (GenBank accession no. X81081). Amino acid sequence comparison with GenBank data indicated 98.2% similarity with coat protein of PPV potyvirus isolated by E. Mais et al. (accession no. X81083) and 97.3% with PPV strain Rankovic (1).The specific DNA fragment, corresponding to predicted coat protein sequence size, was cloned into Escherichia coli pUC57 for DNA sequencing. Expression of the cloned sequence in bacteria and yeast expression systems is under investigation. The presence of PPV in plum trees in the 9-year-old collection at Babtai was confirmed by DAS-ELISA in 1997 and again in 1998. PPV was then detected in 20% of symptomatic trees of three cultivars. The Lithuanian PPV isolate reacted positively with “universal” Mab.5b and with a Mab (Mab.4DG5) specific for PPV-D. No reaction was observed with Mabs specific for PPV-M (Mab.AL), PPV-C (Mab.AC and Mab.TUV), and PPV-El Amar (Mab.EA24). PPV-971 seems to be a typical member of the less aggressive Dideron strain cluster of PPV (D. Boscia, personal communication). This is the first report of PPV in Lithuania and confirms the necessity for continuing the precautionary measures established in this country for indexing of nursery plum trees used for graft propagation. References: (1) S. Lain et al. Virus Res. 13:157, 1989. (2) J. Logemann et al. Anal. Biochem. 163:16, 1987. (3) M. Nemeth. OEPP/EPPO Bull. 24:525, 1994.

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First Report on the Natural Occurrence of Cherry virus A in Mirabelle Plum (Prunus domestica var. insititia)

Plant Disease ◽

10.1094/pd-89-0433a ◽

2005 ◽

Vol 89 (4) ◽

pp. 433-433 ◽

Cited By ~ 5

Author(s):

L. Svanella-Dumas ◽

A. Marais ◽

P. Gentit ◽

J. Lamorte ◽

T. Candresse

Keyword(s):

Natural Infection ◽

Plant Viruses ◽

Natural Occurrence ◽

Prunus Domestica ◽

Rt Pcr ◽

Pcr Assay ◽

First Report ◽

Specific Pcr ◽

Specific Pcr Assay ◽

Prunus Spp

Cherry virus A (CVA) is a member of the Capillovirus genus (2). It was discovered serendipitously during cloning of the little cherry agent (2) and has since been shown to be relatively widespread in sweet and sour cherry (Prunus cerasus and P. avium) (2,3). It is currently unclear whether CVA is associated with any specific symptoms in these hosts. Although it can be transmitted by grafting and thus propagated in peach, it has not been reported to naturally infect any host other than cherry. Using a degenerate reverse transcription-polymerase chain reaction (RT-PCR) technique targeting a conserved region of the RNA-dependent RNA polymerase (RdRp) and allowing the amplification of members of the Trichovirus, Capillovirus, and Foveavirus genera of filamentous plant viruses (1), a number of symptomatic Prunus spp. germplasm were evaluated. Among these, a cv. Mirabelle dorée accession (Prunus domestica var. insititia P332) of French origin exhibited severe symptoms of rosetting, severe leaf and fruit deformation, and yellow mosaic occasionally turning necrotic. RT-PCR conducted on symptomatic samples produced an amplification product of the expected size (362 bp) in several independent experiments. Sequencing of these products yielded a single sequence (GenBank Accession No. AY792509) with 88.1% nucleotide identity and 93.2% amino acid identity with the type strain of CVA (2). Presence of a CVA isolate was independently confirmed using a CVA-specific PCR assay directly on the original plum material or following experimental transmission by grafting on several new hosts including apricot (P. armeniaca cv. Priana) and plum (P. domestica cv. Prune d'Ente). To our knowledge, this is the first report of natural infection of CVA in plum. The symptoms observed in the infected plum are reminiscent of those caused by severe Prune dwarf virus (PDV) strains. Infection by PDV was confirmed using a PDV-specific PCR assay. The contribution, if any, of CVA to the symptoms observed remains to be evaluated. These findings suggest that the possible presence of CVA in noncherry Prunus spp. hosts should be taken into consideration by quarantine and certification programs. References: (1) X. Foissac et al. Acta Hortic. 550:3743, 2001. (2) W. Jelkmann. J. Gen. Virol. 76:2015, 1995. (3) M. J. Kirby et al. Plant Pathol. 50:6, 2001.

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First Report of Southern bean mosaic virus Infecting French Bean in Morocco

Plant Disease ◽

10.1094/pdis.2004.88.10.1162b ◽

2004 ◽

Vol 88 (10) ◽

pp. 1162-1162 ◽

Cited By ~ 5

Author(s):

E. Segundo ◽

F. M. Gil-Salas ◽

D. Janssen ◽

G. Martin ◽

I. M. Cuadrado ◽

...

Keyword(s):

Mosaic Virus ◽

Sodium Dodecyl ◽

Plant Viruses ◽

Enzyme Linked Immunosorbent Assay ◽

First Report ◽

Sequence Identity ◽

Southern Bean Mosaic Virus ◽

Bean Plants ◽

Symptomatic Leaf ◽

Das Elisa

Common bean (Phaseolus vulgaris L.) is grown on approximately 1,500 ha in commercial greenhouses and is of major economic importance in the Souss-Massa Region, Agadir, Morocco. Since October 2003, symptoms resembling a viral disease, consisting of pod mosaic and distortion and mild to severe mosaic in leaves, have been observed on bean plants in several greenhouses. Mechanical inoculation with symptomatic leaf extracts produced necrotic local lesions on P. vulgaris ‘Pinto’ and systemic symptoms similar to those observed in the naturally infected bean plants P. vulgaris ‘Donna’ (five plants per cultivar). Inoculated and naturally infected samples reacted positively using a double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) to Southern bean mosaic virus (SBMV) (DSMZ, Braunschweig, Germany), a member of the Sobemovirus genus that is transmitted by contact, soil, beetles, and seeds (1). Virions purified from a naturally infected ‘Donna’ plant contained a 30-kDa polypeptide that reacted positively using sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blot analysis with SBMV antiserum (DSMZ). Reverse transcription-polymerase chain reaction amplification with SMBV primers as described by Verhoeven et al. (2) produced an expected 870-bp band. The amplicon was cloned, sequenced (GenBank Accession No. AJ748276), and compared to those isolates available in GenBank and had a nucleotide sequence identity of 87% and a derived amino acid sequence identity of 95% with an SBMV isolate from Spain (2). During a survey in different areas of the Souss-Massa Region, 20 symptomatic leaf and pod samples were randomly collected from 12 greenhouses (50 ha) where significant commercial losses were suffered because of this virus disease, and all samples were positive using DAS-ELISA for SBMV. To our knowledge, this is the first report of SBMV in Morocco. References: (1) J. H. Tremaine and R. I. Hamilton. Southern bean mosaic virus. No. 274 in: Descriptions of Plant Viruses. CMI/AAB, Kew, Surrey, England, 1983. (2) J. Th. J. Verhoeven et al. Eur. J. Plant Pathol. 109:935, 2003.

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First Report of Raspberry bushy dwarf virus on Red Raspberry and Grapevine in Slovenia

Plant Disease ◽

10.1094/pdis.2003.87.9.1148d ◽

2003 ◽

Vol 87 (9) ◽

pp. 1148-1148 ◽

Cited By ~ 12

Author(s):

I. Mavrič ◽

M. Viršček Marn ◽

D. Koron ◽

I. Žežlina

Keyword(s):

Polyclonal Antiserum ◽

Rubus Idaeus ◽

Dwarf Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Natural Occurrence ◽

Red Raspberry ◽

Rt Pcr ◽

First Report ◽

Raspberry Bushy Dwarf Virus ◽

Das Elisa

In 2002, severe vein yellowing and partial or complete yellowing of leaves was observed on some shoots of red raspberry (Rubus idaeus) cvs. Golden Bliss and Autumn Bliss. Sap of infected plants of cv. Golden Bliss was inoculated onto Chenopodium quinoa and Nicotiana benthamiana. Faint chlorotic spots were observed on inoculated leaves of C. quinoa approximately 14 days after inoculation but no systemic symptoms appeared. No symptoms were observed on N. benthamiana. Raspberry bushy dwarf virus (RBDV) was detected in the original raspberry plant using double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) with polyclonal antiserum (Loewe Biochemica, Sauerlach, Germany). Systemic infections of inoculated C. quinoa and N. benthaminana were confirmed using DAS-ELISA. In 2001 and 2002, unusual virus symptoms were observed on grapevine grafts (Vitis vinifera) of cv. Laški Rizling. Symptoms appeared as curved line patterns and yellowing of the leaves. No nepoviruses were found in symptomatic plants, but RBDV was confirmed using DAS-ELISA. RBDV infection was later confirmed in grapevine cv. Štajerska Belina with similar symptoms. RBDV was transmitted mechanically from grapevine to C. quinoa where it was detected by immunocapture-reverse transcription-polymerase chain reaction (IC-RT-PCR). IC-RT-PCR was used to amplify a part of the coat protein gene of the virus from raspberry and grapevine, and the amplification products were sequenced (1). The obtained sequence shared at least 93% nucleotide sequence identity with other known RBDV sequences, which confirmed the serological results. To our knowledge, this is the first report of the natural occurrence of RBDV in grapevine and also of RBDV infection of red raspberry in Slovenia. Reference: (1) H. I. Kokko et al. Biotechniques 20:842, 1996.

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First Report of Nasturtium as a Natural Host of Cherry leaf roll virus on Amsterdam Island

Plant Disease ◽

10.1094/pdis-94-4-0477b ◽

2010 ◽

Vol 94 (4) ◽

pp. 477-477 ◽

Cited By ~ 5

Author(s):

A. Marais ◽

C. Faure ◽

T. Candresse ◽

M. Hullé

Keyword(s):

Natural Infection ◽

Leaf Roll ◽

Plant Viruses ◽

Natural Host ◽

Mechanical Transmission ◽

Sequence Information ◽

Coding Region ◽

Rt Pcr ◽

First Report ◽

Cherry Leaf Roll Virus

Cherry leaf roll virus (CLRV) is a well-known virus belonging to the genus Nepovirus, but unlike most members of this genus, it is not known to be transmitted by nematodes but only through seeds and pollen. Since its first description in 1955 on Prunus avium L. in England (1), CLRV has been shown to have a worldwide distribution and a wide natural host range. During a survey of plant viruses in the French sub-Antarctic islands, samples from nasturtium plants (Tropaeolum majus), an introduced plant species, showing symptoms of leaf mosaic, deformation, and veinal necrosis were collected on Amsterdam Island. Upon mechanical transmission with sap extracts, necrotic ringspot and oak-leaf symptoms typical of Nepovirus infection were observed on the leaves of inoculated Nicotiana clevelandii and N. tabacum plants. Inoculation of healthy nasturtium plants resulted in mosaic and pin-point necrosis symptoms. Electron microscopy on negatively stained sap extracts revealed the presence of icosahedral virions, 28 to 30 nm in diameter, in the symptomatic Nicotiana leaves. Amplification by reverse transcription (RT)-PCR with a polyvalent test, which identifies viruses belonging to the family Comoviridae (2), yielded the expected 248-bp fragment. Sequencing of the cloned amplicon showed 80% nucleotide and 90% amino acid identity with a part of the RNA dependent RNA polymerase (RdRp) of CLRV (CAE83562). To confirm the presence of CLRV, an approximate 4.6-kbp cDNA fragment was PCR amplified from double-stranded RNAs purifed from infected Nicotiana plants using the sense primer 5′-GTGGGACTGCCATGCACCTACTC-3′ and an oligo-T25 as antisense primer. This PCR product (GenBank Accession No. GU167974) spans the region between the VPg gene and the polyA tail at the 3′ end of the genome and thus provides approximately 2.8 kb of new internal sequence information on RNA1 of CLRV. The presence of CLRV in the initial nasturtium samples was confirmed with a CLRV-specific RT-PCR assay that amplifies the 3′ non-coding region of the CLRV genome (3). Sequence of the amplified fragment showed it to be identical to the corresponding part of the 3′ non-coding region of 4.6-kbp clone obtained from the CLRV isolate mechanically transmitted to the N. tabacum and N. clevelandii plants. Experimental infection of nasturtium by CLRV has been reported (4), but to the best of our knowledge these results represent the first report of natural infection of T. majus by CLRV. Given its seed transmissible character in many hosts, CLRV likely was introduced in infected seeds of T. majus imported to the remote sub-Antarctic Amsterdam Island. References: (1) R. Cropley. Ann. Appl. Biol. 49:524, 1961. (2) V. Maliogka et al. J. Phytopathol. 152:404, 2004. (3) K. Rebenstorf et al. J. Virol. 80:2453, 2006. (4) K. Schmelzer. Phytopathol. Z. 55:317, 1966.

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First Report of Tomato Spotted Wilt Tospovirus Infection of Watermelon in Georgia

Plant Disease ◽

10.1094/pdis.1998.82.3.351c ◽

1998 ◽

Vol 82 (3) ◽

pp. 351-351 ◽

Cited By ~ 6

Author(s):

S. S. Pappu ◽

H. R. Pappu ◽

R. D. Gitaitis ◽

J. D. Gay

Keyword(s):

Natural Infection ◽

Late Summer ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

First Report ◽

Nucleocapsid Gene ◽

Tomato Spotted Wilt ◽

Pcr Product ◽

Polymerase Chain ◽

Potential Impact

In 1996, volunteer watermelon plants in a tobacco field in Coffee County, GA, exhibited foliar symptoms that included necrotic ring spots and veinal necrosis. Watermelon plants from experimental plots of the Coastal Plain Experiment Station in Tifton, GA, similarly showed necrotic lesions, often resulting in necrotic ring spots during the late summer of 1997. Out of 16 samples tested for the presence of tomato spotted wilt tospovirus (TSWV) with a commercially available enzyme-linked immunosorbent assay (ELISA) kit (Agdia, Elkhart, IN), six were positive for TSWV. Primers specific to the nucleocapsid gene of TSWV were used in a reverse transcription-polymerase chain reaction assay (RT-PCR) (1) to verify the presence of TSWV. RT-PCR gave an expected PCR product of approximately 350 bp. The amplicon was cloned in pGEM-T vector and the recombinant clone was sequenced. The sequence of the cloned PCR product confirmed the identity of TSWV, thus verifying TSWV infection of watermelon. The potential impact of TSWV on watermelon crop in Georgia will be investigated. This is the first report of natural infection of watermelon by TSWV in Georgia. Reference: (1) H. R. Pappu et al. Tobacco Sci. 40:74, 1996.

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First Report of Tomato spotted wilt virus on a New Host Leuzea carthamoides in Bulgaria and the World

Plant Disease ◽

10.1094/pdis-11-12-1005-pdn ◽

2013 ◽

Vol 97 (9) ◽

pp. 1258-1258 ◽

Cited By ~ 2

Author(s):

B. Dikova ◽

N. Petrov ◽

A. Djourmanski ◽

H. Lambev

Keyword(s):

Tomato Spotted Wilt Virus ◽

Plant Viruses ◽

Rt Pcr ◽

First Report ◽

Tomato Spotted Wilt ◽

The World ◽

Systemic Symptoms ◽

Wilt Virus ◽

The Town ◽

Das Elisa

The Siberian plant Leuzea carthamoides or maral root was introduced to Europe as a medicinal crop. Tomato spotted wilt virus (TSWV), genus Tospovirus, family Bunyaviridae, caused a harmful outbreak on L. carthamoides in central Bulgaria near the town of Kazanluk in 2009. In 2011, TSWV was identified on young sprouts from the rootages of L. carthamoides in the same place near the town of Kazanluk, Bulgaria, by means of indicator (test) plants, double antibody sandwich (DAS)-ELISA, and reverse transcription (RT)-PCR. Disease symptoms were small yellow spots on the young leaves grown from the tested sprouts and distortions of the leaf lamina. The old leaves had large yellow spots and necrosis, without deformations. Most of those L. carthamoides plants with such symptoms died in the second and third year. The number of the plants in the plantations decreased 20 to 40% during the 3-year period and some of these losses were from the virus disease except the environment conditions. DAS-ELISA was carried out with polyclonal TSWV antiserum of LOEWE Biochemica, GmbH, Germany. We obtained positive extinction values ODλ 405nm 0.358 ± 0.091 compared to the negative 0.053 ± 0.016 and the positive control 0.510 at a confidential interval at P ≤ 0.05. TSWV symptoms were observed on the following indicator plants according to Antignus et al. (1) and DPV/412 (2): Chenopodium quinoa, Cucumis sativus, Datura stramonium, Nicotiana glutinosa, N. rustica, N. tabacum cv. Samsun NN, and Petunia hybrida. TSWV caused on C. quinoa and on cotyledons of C. sativus cv. Delikates local chlorotic lesions only. In this TSWV differed from CMV because CMV caused systemic mosaic symptoms. Local small necrotic lesions and no systemic symptoms were observed on P. hybrida. We noticed systemic symptoms caused from TSWV on D. stramonium, N. glutinosa, N. rustica, and N. tabacum cv. Samsun NN. The systemic symptoms were chlorotic spots, concentric ring spots, and line patterns proceeding to necrosis. RT-PCR, adapted by Mumford et al. (3), was carried out on samples of L. carthamoides. Oligonucleotide primer sequences were used in accordance with Mumford et al. (3). The DNA fragment was visualized by UV trans-illumination. A fragment of the TSWV genome with a length of 276 base pairs was found in three young L. carthamoides leaf samples taken from the sprouts (marker 100 bp). The PCR fragment was sequenced and deposited to NCBI with GenBank Accession No. KC918808. PCR master mix without RNA template was used as a negative control. L. carthamoides is a newly established TSWV host in the world. To our knowledge, this is the first report of TSWV in L. carthamoides identified by RT-PCR. References: (1) Y. Antignus et al. Phytoparasitica 25:319, 1997. (2) R. Kormelink. Descriptions of Plant Viruses, p. 412, 2005. (3) R. A. Mumford et al. J. Virol. Methods 57:109, 1996.

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First Report of Soybean dwarf virus on Soybean in Wisconsin

Plant Disease ◽

10.1094/pdis.2004.88.11.1285a ◽

2004 ◽

Vol 88 (11) ◽

pp. 1285-1285 ◽

Cited By ~ 7

Author(s):

A. Phibbs ◽

A. Barta ◽

L. L. Domier

Keyword(s):

Leaf Tissue ◽

Dwarf Virus ◽

Economic Losses ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

First Report ◽

Elisa Testing ◽

Soybean Plants ◽

Soybean Dwarf Virus ◽

Das Elisa

Soybean dwarf virus (SbDV) causes widespread economic losses on soybean (Glycine max (L.) Merr.) in Japan (4), and has been reported on soybean in Virginia (2), in various legumes in the southeastern United States (1), and in peas in California (3). During late July and early August of 2003, soybean plants in Wisconsin were surveyed for SbDV. In 286 soybean fields at the R2-R4 growth stage, the uppermost fully unfurled leaf was collected from 10 plants at each of five sites. Samples were collected at random without regard to symptoms. SbDV symptom information was not recorded. Samples were stored on ice until frozen at -80°C. Five fields in four Wisconsin counties (Columbia, Lafayette, Sauk, and Waushara) tested positive for SbDV using double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). DAS-ELISA testing was conducted with reagents from Agdia, Inc (Elkhart, IN) following the manufacturer's protocol. Absorbance was read at 405 nm with a Stat Fax 2100 microplate reader (Awareness Technology, Inc., Palm City, FL) or visually evaluated. DAS-ELISA did not discriminate between strains of SbDV. The presence of SbDV was confirmed, and strain identity was inferred as dwarfing strain using reverse transcription-polymerase chain reaction (RT-PCR). Total RNA was extracted from homogenized leaf tissue, reverse transcribed, and amplified with the SuperScript One Step RT-PCR System (Invitrogen, Carlsbad, CA) and SbDV-specific primers (5′-CTGCTTCTGGTGATTACACTGCCG-3′ and 5′-CGCTTTCATTTAACGYCATCAAAGGG-3′). Size of the RT-PCR products (110 bp) was consistent with the dwarfing strain, SbDV-D. All locations that tested positive for SbDV showed soybean aphids, Aphis glycines Matsumura (Homoptera: Aphididae), on 100% of soybean plants. Several aphid species have been reported to vector SbDV, but at this time, vector relations in the Wisconsin infections are unknown. To our knowledge, this is the first report of SbDV infecting soybean in Wisconsin. References: (1) V. D. Damsteegt et al. Plant Dis. 79:48, 1995. (2) A. Fayad et al. Phytopathology (Abstr.) 90(Suppl.):S132, 2000. (3) G. R. Johnstone et al. Phytopathology (Abstr.) 74:795(A43), 1984. (4) T. Tamada et al. Ann. Phytopathol. Soc. Jpn. 35:282, 1969.

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First Report of Natural Infection of Penstemon acuminatus with Cucumber mosaic virus in the Treasure Valley Region of Idaho and Oregon

Plant Disease ◽

10.1094/pdis-93-7-0762a ◽

2009 ◽

Vol 93 (7) ◽

pp. 762-762 ◽

Cited By ~ 1

Author(s):

R. K. Sampangi ◽

C. Almeyda ◽

K. L. Druffel ◽

S. Krishna Mohan ◽

C. C. Shock ◽

...

Keyword(s):

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Great Basin ◽

Natural Infection ◽

The United States ◽

Native Plant ◽

Rt Pcr ◽

Cmv Infection ◽

Spot Virus ◽

First Report

Penstemons are perennials that are grown for their attractive flowers in the United States. Penstemon species (P. acuminatus, P. deustus, and P. speciosus) are among the native forbs considered as a high priority for restoration of great basin rangelands. During the summer of 2008, symptoms of red spots and rings were observed on leaves of P. acuminatus (family Scrophulariaceae) in an experimental trial in Malheur County, Oregon where the seeds from several native forbs were multiplied for restoration of range plants in intermountain areas. These plants were cultivated as part of the Great Basin Native Plant Selection and Increase Project. Several native wildflower species are grown for seed production in these experimental plots. Plants showed red foliar ringspots and streaks late in the season. Fungal or bacterial infection was ruled out. Two tospoviruses, Impatiens necrotic spot virus and Tomato spotted wilt virus, and one nepovirus, Tomato ring spot virus, are known to infect penstemon (2,3). Recently, a strain of Turnip vein-clearing virus, referred to as Penstemon ringspot virus, was reported in penstemon from Minnesota (1). Symptomatic leaves from the penstemon plants were negative for these viruses when tested by ELISA or reverse transcription (RT)-PCR. However, samples were found to be positive for Cucumber mosaic virus (CMV) when tested by a commercially available kit (Agdia Inc., Elkhart, IN). To verify CMV infection, total nucleic acid extracts from the symptomatic areas of the leaves were prepared and used in RT-PCR. Primers specific to the RNA-3 of CMV were designed on the basis of CMV sequences available in GenBank. The primer pair consisted of CMV V166: 5′ CCA ACC TTT GTA GGG AGT GA 3′ and CMV C563: 5′ TAC ACG AGG ACG GCG TAC TT 3′. An amplicon of the expected size (400 bp) was obtained and cloned and sequenced. BLAST search of the GenBank for related sequences showed that the sequence obtained from penstemon was highly identical to several CMV sequences, with the highest identity (98%) with that of a sequence from Taiwan (GenBank No. D49496). CMV from infected penstemon was successfully transmitted by mechanical inoculation to cucumber seedlings. Infection of cucumber plants was confirmed by ELISA and RT-PCR. To our knowledge, this is the first report of CMV infection of P. acuminatus. With the ongoing efforts to revegetate the intermountain west with native forbs, there is a need for a comprehensive survey of pests and diseases affecting these plants. References: (1) B. E. Lockhart et al. Plant Dis. 92:725, 2008. (2) D. Louro. Acta Hortic. 431:99, 1996. (3) M. Navalinskiene et al. Trans. Estonian Agric. Univ. 209:140, 2000.

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