First Report of Tomato spotted wilt virus Causing Potato Tuber Necrosis in Texas

In the summer of 2008, potato (Solanum tuberosum L.) tubers (cvs. FL1867, FL2053, and FL1922) from commercial fields near Dalhart, TX were observed with distinct external erumpent rings and severe internal discolorations including blotches, spots, and dry, cork-like tissue. The presence of rings suggested the possible involvement of one or more viruses. Nucleic acid from seven of eight symptomatic tubers received in Washington (cvs. FL1867 and FL1922) tested positive for Tomato spotted wilt virus (TSWV) by reverse transcription (RT)-PCR with primers TSWV 1 and 2 (3). Similarly, tubers (cvs. FL1867 and FL2053) received in North Dakota tested positive for TSWV with forward (S1983) and reverse (S2767) primers of Tsompana et al. (4). The 777-bp amplicon obtained with primers TSWV 1 and 2 and the 803-bp amplicon obtained with primers S1983 and S2767 were cloned and three clones of each were sequenced. Analysis of the consensus sequences and BLAST comparisons confirmed the Washington and North Dakota sequences were indeed TSWV in origin and were each 98 to 99% identical to the corresponding nucleocapsid region of a number of TSWV isolates and most closely related to an isolate detected in eastern black nightshade from Colorado (GenBank No. AY777475). The deduced amino acid sequences of the 777-bp nucleocapsid open reading frame differed from AY777475 at only two residues in each of the Washington and North Dakota sequences. The Washington and North Dakota derived sequences were deposited with GenBank (Nos. FJ882069 and FJ882070, respectively). None of the eight symptomatic tubers tested positive for Tobacco rattle virus (TRV), Alfalfa mosaic virus (AMV), or the necrotic strains of Potato virus Y (PVY) by RT-PCR. Mechanical transmission tests were conducted by grinding symptomatic tissue of a TSWV-positive FL1867 tuber in 10 volumes of 30 mM potassium phosphate buffer, pH 8.0, containing 10 mM of sodium diethyldithiocarbamate and 10 mM of sodium thioglycollate and rub inoculated onto Carborundum-dusted leaves of Samsun NN tobacco. Approximately 10 days after inoculation, chlorotic-necrotic rings were present on the inoculated leaves and circular necrotic lesions developed on the upper leaves. Dark stem lesions were also present on inoculated tobacco, and after 3 weeks, the upper leaves developed severe, spreading lesions. Tissue from the symptomatic tobacco tested positive for TSWV by RT-PCR (primers TSWV 1 and 2) and also with a TSWV-specific ImmunoStrip (Agdia, Inc., Elkhart, IN), but tested negative for TRV, AMV, and PVY by RT-PCR. TSWV has been reported on field-grown potatoes in North Carolina (1) and has been reported on potatoes in Australia (2) and in other parts of the world (referenced in 1). To our knowledge, this is the first report associating TSWV with tuber necrosis on potatoes in Texas. References: (1) J. A. Abad et al. Am. J. Potato Res. 82:255, 2005. (2) L. J. Latham and R. A. C. Jones. Aust. J. Agric. Res. 48:359, 1997. (3) R. Navarre et al. Am. J. Potato Res. 86:88, 2009. (4) M. Tsompana et al. Mol. Ecol. 14:53, 2005.

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First Report of Tomato spotted wilt virus in Blackberry Lily in North America

Plant Disease ◽

10.1094/pdis.2003.87.1.102c ◽

2003 ◽

Vol 87 (1) ◽

pp. 102-102 ◽

Cited By ~ 3

Author(s):

S. Adkins ◽

L. Breman ◽

C. A. Baker ◽

S. Wilson

Keyword(s):

North America ◽

Tomato Spotted Wilt Virus ◽

Amino Acid Sequences ◽

South Florida ◽

N Gene ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

First Report ◽

Tomato Spotted Wilt ◽

Wilt Virus

Blackberry lily (Belamcanda chinensis (L.) DC.) is an herbaceous perennial in the Iridaceae characterized by purple-spotted orange flowers followed by persistent clusters of black fruit. In July 2002, virus-like symptoms including chlorotic ringspots and ring patterns were observed on blackberry lily leaves on 2 of 10 plants in a south Florida ornamental demonstration garden. Inclusion body morphology suggested the presence of a Tospovirus. Tomato spotted wilt virus (TSWV) was specifically identified by serological testing using enzyme-linked immunosorbent assay (Agdia, Elkhart, IN). Sequence analysis of a nucleocapsid (N) protein gene fragment amplified by reverse transcription-polymerase chain reaction (RT-PCR) with primers TSWV723 and TSWV722 (1) from total RNA confirmed the diagnosis. Nucleotide and deduced amino acid sequences of a 579 base pair region of the RT-PCR product were 95 to 99% and 95 to 100% identical, respectively, to TSWV N-gene sequences in GenBank. Since these 2-year-old plants were grown on-site from seed, they were likely inoculated by thrips from a nearby source. Together with a previous observation of TSWV in north Florida nursery stock (L. Breman, unpublished), this represents, to our knowledge, the first report of TSWV infection of blackberry lily in North America although TSWV was observed in plants of this species in Japan 25 years ago (2). References: (1) S. Adkins, and E. N. Rosskopf. Plant Dis. 86:1310, 2002. (2) T. Yamamoto and K.-I. Ohata. Bull. Shikoku Agric. Exp. Stn. 30:39, 1977.

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First Report of Tomato spotted wilt virus on Chrysanthemum in Serbia

Plant Disease ◽

10.1094/pdis-08-12-0778-pdn ◽

2013 ◽

Vol 97 (1) ◽

pp. 150-150 ◽

Cited By ~ 7

Author(s):

I. Stanković ◽

A. Bulajić ◽

A. Vučurović ◽

D. Ristić ◽

K. Milojević ◽

...

Keyword(s):

Tomato Spotted Wilt Virus ◽

Disease Incidence ◽

N Gene ◽

Impatiens Necrotic Spot Virus ◽

Maximum Parsimony Tree ◽

Rt Pcr ◽

First Report ◽

Tomato Spotted Wilt ◽

Negative Controls ◽

Wilt Virus

In July 2011, greenhouse-grown chrysanthemum hybrid plants (Chrysanthemum × morifolium) with symptoms resembling those associated with tospoviruses were observed in the Kupusina locality (West Bačka District, Serbia). Disease incidence was estimated at 40%. Symptomatic plants with chlorotic ring spots and line patterns were sampled and tested by double antibody sandwich (DAS)-ELISA using polyclonal antisera (Bioreba AG, Reinach, Switzerland) against the two of the most devastating tospoviruses in the greenhouse floriculture industry: Tomato spotted wilt virus (TSWV) and Impatiens necrotic spot virus (INSV) (2). Commercial positive and negative controls and extracts from healthy chrysanthemum tissue were included in each ELISA. TSWV was detected serologically in 16 of 20 chrysanthemum samples and all tested samples were negative for INSV. The virus was mechanically transmitted from ELISA-positive chrysanthemum samples to five plants each of both Petunia × hybrida and Nicotiana tabacum ‘Samsun’ using chilled 0.01 M phosphate buffer (pH 7) containing 0.1% sodium sulfite. Inoculated plants produced local necrotic spots and systemic chlorotic/necrotic concentric rings, consistent with symptoms caused by TSWV (1). The presence of TSWV in ELISA-positive chrysanthemum plants and N. tabacum‘Samsun’ was further confirmed by conventional reverse transcription (RT)-PCR. Total RNAs were extracted with an RNeasy Plant Mini Kit (Qiagen, Hilden, Germany). RT-PCR was performed with the One-Step RT-PCR Kit (Qiagen) using primers TSWVCP-f/TSWVCP-r specific to the nucleocapsid protein (N) gene (4). A Serbian isolate of TSWV from tobacco (GenBank Accession No. GQ373173) and RNA extracted from a healthy chrysanthemum plant were used as positive and negative controls, respectively. An amplicon of the correct predicted size (738-bp) was obtained from each of the plants assayed, and that derived from chrysanthemum isolate 529-11 was purified (QIAqick PCR Purification Kit, Qiagen) and sequenced (JQ692106). Sequence analysis of the partial N gene, conducted with MEGA5 software, revealed the highest nucleotide identity of 99.6% (99% amino acid identity) with 12 TSWV isolates deposited in GenBank originating from different hosts from Italy (HQ830186-87, DQ431237-38, DQ398945), Montenegro (GU355939-40, GU339506, GU339508), France (FR693055-56), and the Czech Republic (AJ296599). The consensus maximum parsimony tree obtained on a 705-bp partial N gene sequence of TSWV isolates available in GenBank revealed that Serbian TSWV isolate 529-11 from chrysanthemum was clustered in the European subpopulation 2, while the Serbian isolates from tomato (GU369723) and tobacco (GQ373172-73 and GQ355467) were clustered in the European subpopulation 1 denoted previously (3). The distribution of TSWV in commercial chrysanthemum crops is wide (2). To our knowledge, this is the first report of TSWV infecting chrysanthemum in Serbia. Since chrysanthemum popularity and returns have been rising rapidly, the presence of TSWV may significantly reduce quality of crops in Serbia. References: (1) Anonymous. OEPP/EPPO Bull. 34:271, 2004. (2) Daughtrey et al. Plant Dis. 81:1220, 1997. (3) I. Stanković et al. Acta Virol. 55:337, 2011. (4) A. Vučurović et al. Eur. J. Plant Pathol. 133:935, 2012.

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First Report of Tomato spotted wilt virus Infection of Tomatillo in Georgia

Plant Disease ◽

10.1094/pdis.2000.84.10.1155b ◽

2000 ◽

Vol 84 (10) ◽

pp. 1155-1155 ◽

Cited By ~ 3

Author(s):

J. C. Díaz-Pérez ◽

H. R. Pappu

Keyword(s):

Tomato Spotted Wilt Virus ◽

Plant Size ◽

Coding Region ◽

Rt Pcr ◽

First Report ◽

Nucleocapsid Gene ◽

Tomato Spotted Wilt ◽

Pcr Product ◽

The University ◽

Wilt Virus

During the 2000 spring season, tomatillo (Physalis ixocarpa) plants showing chlorotic streaks on leaves were observed in an experimental plot of the University of Georgia's Coastal Plain Experiment Station in Tift County, GA. Leaf samples from 192 plants were collected. These included plants that had chlorotic streaks and those without obvious symptoms. Samples were tested by ELISA using a commercially available Tomato spotted wilt virus (TSWV) detection kit (Agdia Inc., Elkhart, IN). TSWV was found in 10 samples that had chlorotic streaks on leaves, and the remaining plants with no obvious symptoms were negative for TSWV. Infected plants were found in both cultivars, Verde Puebla and Toma Verde. The presence of the virus had no apparent effect on plant size or fruit appearance. TSWV infection of the ELISA-positive samples was further verified by immunocapture reverse transcription-polymerase chain reaction (IC-RT-PCR) (1). The primer pair (5′-ATGTCTAAGGTTAAGCTC-3′ and 5′ TTAAGCAAGTTCTGTGAG-3′) represented the first and last 18 bases of the coding region of the nucleocapsid gene of TSWV, respectively, and produced approximately 800-bp PCR product (1). IC-RT-PCR gave a single DNA band of expected size and no amplification was found in the uninfected control. This is the first report of TSWV on tomatillo in Georgia. Reference: (1) R. K. Jain et al. Plant Dis. 82:900, 1998.

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First Report of Tomato spotted wilt virus on Brugmansia sp. in Serbia

Plant Disease ◽

10.1094/pdis-10-12-0937-pdn ◽

2013 ◽

Vol 97 (6) ◽

pp. 850-850 ◽

Cited By ~ 3

Author(s):

D. Nikolić ◽

I. Stanković ◽

A. Vučurović ◽

D. Ristić ◽

K. Milojević ◽

...

Keyword(s):

Mosaic Virus ◽

Tomato Spotted Wilt Virus ◽

N Gene ◽

Broad Host Range ◽

Rt Pcr ◽

First Report ◽

Tomato Spotted Wilt ◽

Plant Pathol ◽

Negative Controls ◽

Wilt Virus

Brugmansia (Brugmansia spp.), also known as Angel's trumpet, is a perennial shrub in the Solanaceae that is a popular landscape plant in the tropics and subtropics, and potted plant in temperate regions. In April 2012, virus-like symptoms including chlorotic leaf patterns and curling followed by necrosis and distortion of leaves were observed on five outdoor-grown brugmansia plants in a private garden in Mackovac, Rasina District, Serbia. Symptomatic leaves were tested for the presence of several common ornamental viruses including Tomato spotted wilt virus (TSWV), Impatiens necrotic spot virus (INSV), Cucumber mosaic virus (CMV), and Tobacco mosaic virus (TMV) by commercial double-antibody sandwich (DAS)-ELISA diagnostic kits (Bioreba AG, Reinach, Switzerland). Commercial positive and negative controls and extract from healthy brugmansia leaves were included in each ELISA. TSWV was detected serologically in all five brugmansia samples and all tested samples were negative for INSV, CMV, and TMV. The virus was mechanically transmitted from an ELISA-positive sample (41-12) to five plants of each Petuina × hybrida and Nicotiana glutinosa. Inoculated P. × hybrida plants showed local necrotic lesions and N. glutinosa showed mosaic and systemic necrosis 4 and 12 days post-inoculation, respectively, which were consistent with symptoms caused by TSWV (1). For further confirmation of TSWV infection, reverse transcription (RT)-PCR was performed with the OneStep RT-PCR (Qiagen, Hilden, Germany) using a set of TSWV-specific primers, TSWV CP-f and TSWV CP-r (4), designed to amplify a 738-bp fragment of the nucleocapsid protein (N) gene. Total RNAs from naturally infected brugmansia and symptomatic N. glutinosa plants were extracted using the RNeasy Plant Mini Kit (Qiagen). Total RNAs obtained from the Serbian tobacco isolate of TSWV (GenBank Accession No. GQ373173) and healthy brugmansia plants were used as positive and negative controls, respectively. The expected size of the RT-PCR product was amplified from symptomatic brugmansia and N. glutinosa but not from healthy tissues. The amplified product derived from the isolate 41-12 was sequenced directly after purification with the QIAquick PCR Purification kit (Qiagen), deposited in GenBank (JX468080), and subjected to sequence analysis by MEGA5 software (3). Sequence comparisons revealed that the Serbian isolate 41-12 shared the highest nucleotide identity of 99.9% (99.5% amino acid identity) with an Italian TSWV isolate P105/2006RB (DQ915946) originating from pepper. To our knowledge, this is the first report of TSWV on brugmansia in Serbia. Due to the increasing popularity and economic importance of brugmansia as an ornamental crop, thorough inspections and subsequent testing for TSWV and other viruses are needed. This high-value ornamental plant may act also as reservoir for the virus that can infect other ornamentals and cultivated crops, considering that TSWV has a very broad host range (2). References: (1) Anonymous. OEPP/EPPO Bull. 34:271, 2004. (2) G. Parrella et al. J. Plant Pathol. 85:227, 2003. (3) K. Tamura et al. Mol. Biol. Evol. 28:2731, 2011. (4) A. Vučurović et al. Eur. J. Plant Pathol. 133:935, 2012.

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First Report of Tomato spotted wilt virus in Lettuce Crops in Saudi Arabia

Plant Disease ◽

10.1094/pdis-05-14-0444-pdn ◽

2014 ◽

Vol 98 (11) ◽

pp. 1591-1591 ◽

Cited By ~ 2

Author(s):

M. A. Al-Saleh ◽

I. M. Al-Shahwan ◽

M. A. Amer ◽

M. T. Shakeel ◽

M. H. Ahmad ◽

...

Keyword(s):

Saudi Arabia ◽

Tomato Spotted Wilt Virus ◽

Post Inoculation ◽

Rt Pcr ◽

Specific Primers ◽

Indicator Plants ◽

First Report ◽

Tomato Spotted Wilt ◽

Local Lesions ◽

Wilt Virus

A survey for viruses in open field lettuce crops was carried out in March 2014 in the Al-Uyaynah area, central region of Saudi Arabia. In one plot, more than 50% of the lettuce plants (Lactuca sativa; hybrid: Romaine), with the majority of the affected plants in the edges of the plot, were showing virus-like symptoms such as necrotic lesions, necrosis of the lamina of the younger leaves, and leaf curling, indicating a possible infection by a Tospovirus, possibly Tomato spotted wilt virus (TSWV). Most of them were dead when the field was visited again 3 weeks later. Samples from 10 symptomatic and two asymptomatic plants were collected. Five of the samples from symptomatic and two from asymptomatic plants were mechanically inoculated onto Nicotiana benthamiana and N. glutinosa (three indicator plants of each species were used for each sample) using 0.1 M phosphate buffer (pH 7) containing 0.01M Na2SO3 mM. All the symptomatic lettuce samples were also tested serologically using polyclonal antisera (3) against TSWV, CMV, and by using monoclonal antibodies against potyviruses. Moreover, total RNA was extracted (1) and detection of TSWV was also attempted with reverse transcription (RT)-PCR using species specific primers (4) for a 276-bp fragment of the L RNA segment. In both serological and molecular methods, positive and negative controls were included. All the mechanically inoculated plants with tissue from the symptomatic lettuce plants of N. benthamiana showed chlorotic local lesions followed by systemic top necrosis 2 to 3 weeks post inoculation. Similarly, all inoculated N. glutinosa plants showed necrotic local lesions followed by systemic chlorosis. However, all the indicator plants mechanically inoculated with tissue from asymptomatic lettuce plants gave no reaction. All the symptomatic lettuce samples reacted positively, while asymptomatic samples reacted negatively in ELISA tests with TSWV antiserum and the presence of the virus was further confirmed by RT-PCR by using specific primers (method A) (4). PCR products of two randomly selected positive samples were directly sequenced and BLAST analysis of the obtained sequences (Accession Nos. KJ701035 and KJ701036) revealed 99% nucleotide and 100% amino acid identity with the deposit sequence in NCBI from South Korea (KC261947). Regarding mechanical inoculation, 10 days post-inoculation, both indicator plants showed typical symptoms of TSWV infection, such as necrotic local lesions, systemic necrotic patterns, and leaf deformation. None of the symptomatic plants was found to be infected with either CMV or potyvirus. To our knowledge, this is the first report of TSWV naturally infecting lettuce in Saudi Arabia; therefore, insect vector and weed management are necessary measures to control the virus spread to other crops such as tomato and pepper (2). References: (1) E. Chatzinasiou et al. J. Virol. Meth. 169:305, 2010. (2) E. K. Chatzivassiliou. Plant Dis. 92:1012, 2008. (3) E. K. Chatzivassiliou et al. Phytoparasitica 28:257, 2000. (4) R. A. Mumford et al. J. Virol. Meth. 46:303, 1994.

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First Report of Tomato spotted wilt virus Infecting African Clover (Trifolium tembense) in Georgia

Plant Disease ◽

10.1094/pdis-93-2-0202c ◽

2009 ◽

Vol 93 (2) ◽

pp. 202-202 ◽

Cited By ~ 2

Author(s):

N. A. Barkley ◽

D. L. Pinnow ◽

M. L. Wang ◽

G. A. Pederson

Keyword(s):

Tomato Spotted Wilt Virus ◽

Plant Genetic Resources ◽

Germplasm Collection ◽

Rt Pcr ◽

First Report ◽

Nucleocapsid Gene ◽

Weed Host ◽

Tomato Spotted Wilt ◽

Wilt Virus ◽

Das Elisa

Tomato spotted wilt virus (TSWV; family Bunyaviridae, genus Tospovirus), which is vectored by several species of thrips (order Thysanoptera, family Thripidae), causes a destructive disease that affects many economically important host plants such as tomatoes, peppers, and peanuts. Controlling the spread of this disease is challenging, and currently, only limited strategies are available to prevent and/or control its dissemination, including early diagnosis, destruction of infected material, and elimination of the vector. TSWV has been previously reported in subterranean clover (Trifolium subterraneum), white clover (T. repens), and various unidentified wild clovers (Trifolium spp.) in North America and Australia (1,3), but never before in an African species. T. tembense (Fresen.), an herbaceous annual African clover that is mainly used for grazing, is part of the national germplasm collection housed at the Plant Genetic Resources Conservation Unit in Griffin, GA. TSWV was found naturally infecting several accessions of this species being grown for regeneration in a greenhouse during 2008. Initial putative identification of the virus was done by visual inspection of host symptoms that included ringspots, necrotic and chlorotic local lesions, sometimes mild systemic wilting, and eventually an overall decline of healthy tissue in the infected plants. This was subsequently confirmed by double-antibody sandwich (DAS)-ELISA and reverse transcription (RT)-PCR. Primers (5′-ATGTCTAAGGTTAAGCTC-3′ forward and 5′-TTAAGCAAGTTCTGTGAG-3′ reverse) targeted the nucleocapsid gene of TSWV and amplified an expected product of approximately 800 bp (2). No product was amplified in any of the negative controls. Twenty-six individuals representing twelve plant accessions (PI 517788, 517790, 517792, 517793, 517809, 517832, 517842, 517845, 517851, 517871, 517876, and 517889) were screened for TSWV. Two to three individuals were targeted from each accession. Samples were chosen on the basis of the availability of leaf tissue to perform two diagnostic assays, ELISA and RT-PCR. Samples chosen for this study were all naturally infected by thrips. All but four individuals representing two plant accessions tested positive for the virus. The RT-PCR data substantiated the DAS-ELISA results and confirmed the suspected infection. More than 26% of the positive samples naturally infected by TSWV were further characterized by purifying and sequencing (bidirectionally) the RT-PCR product on an automated CEQ 8000 sequencer (Beckman Coulter, Fullerton, CA). The resulting sequences were aligned and edited using AlignIR (LI-COR, Lincoln, NE). More than 700 bp of sequence data (GenBank Accession No. FJ183743–FJ183746) was compiled and they displayed 98% identity with deposited TSWV nucleocapsid gene sequences in GenBank, with no similarity to any other targets. To our knowledge, this is the first report of TSWV infection in T. tembense. Accessions potentially resistant to TSWV within this species were identified and need to be further substantiated. T. tembense is a wild, native clover in Africa and could serve as a weed host for infection of nearby agronomically important crops. References: (1) I. Bitterlich and L. S. MacDonald. Can. Plant Dis. Surv. 73:137, 1993. (2) R. J. Holguín-Peña and E. O. Rueda-Puente. Plant Dis. 91:1682, 2007. (3) C. R. Wilson. Plant Pathol. 47:171, 1998.

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First Report of Tomato spotted wilt virus in Brugmansia suaveolens in Korea

Plant Disease ◽

10.1094/pdis-02-14-0173-pdn ◽

2014 ◽

Vol 98 (9) ◽

pp. 1283-1283

Author(s):

S.-K. Choi ◽

I.-S. Cho ◽

G.-S. Choi ◽

J.-Y. Yoon

Keyword(s):

Mosaic Virus ◽

Tomato Spotted Wilt Virus ◽

Korean Isolate ◽

Rt Pcr ◽

First Report ◽

Tomato Spotted Wilt ◽

Pcr Product ◽

Brugmansia Suaveolens ◽

Plant Pathol ◽

Wilt Virus

Brugmansia suaveolens, also known as angel's trumpet, is a semi-woody shrub or a small tree. Because flowers of B. suaveolens are remarkably beautiful and sweetly fragrant, B. suaveolens is grown as ornamentals outdoors year-round in the tropics and subtropics, and as potted plants in temperate regions (1). In February 2013, virus-like symptoms including mosaic symptoms followed by distortion of leaves were observed in a potted B. suaveolens in a nursery in Chung-Nam Province, Korea. Symptomatic leaves were analyzed for the presence of several ornamental viruses including Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV), Tomato bush stunt virus (TBSV), and Tomato spotted wilt virus (TSWV) by immune-strip diagnostic kits that were developed by our laboratory. Positive controls and extract from healthy leaves of B. suaveolens as a negative control were included in each immune-strip assay. TSWV was detected serologically from the naturally infected B. suaveolens, but CMV, TBSV, and TMV were not detected from the B. suaveolens. The presence of TSWV (named TSWV-AT1) was confirmed by commercially available double-antibody sandwich (DAS)-ELISA kits (Agdia, Elkhart, IN). TSWV-AT1 was mechanically transmitted from the ELISA-positive B. suaveolens to Capsicum annuum and Nicotiana glutinosa, respectively. Inoculated C. annuum showed chlorotic rings in the inoculated leaves and inoculated N. glutinosa produced mosaic and systemic necrosis in the inoculated leaves after 7 days inoculation, respectively, which were consistent with symptoms caused by TSWV (2). To confirm further TSWV-AT1 infection, reverse transcription (RT)-PCR was performed using the One-Step RT-PCR (Invitrogen, Carlsbad, CA) with TSWV-specific primers, TSWV-NCP-For and TSWV-NCP-Rev (3), designed to amplify a 777-bp cDNA of the nucleocapsid protein (NCP) gene. Total RNAs from naturally infected B. suaveolens, symptomatic C. annuum, and N. glutinosa were extracted using RNeasy Plant Mini Kit (Qiagen, Valencia, CA). Total RNAs obtained from a Korean isolate of TSWV (Accession No. JF730744) and healthy B. suaveolens were used as positive and negative controls, respectively. The expected size of the RT-PCR product was amplified from symptomatic B. suaveolens, C. annuum, and N. glutinosa but not from healthy leaves of B. suaveolens. The amplified RT-PCR product from TSWV-AT1 was directly sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the TSWV-AT1 NCP sequence (AB910533) with NCP sequences of other TSWV isolates using MEGA5 software (4) revealed 99.0% aa identity with an Korean TSWV isolate (AEB33895) originating from tomato. These results provide additional confirmation of TSWV-AT1 infection. It is known that high-value ornamentals may act also as reservoirs for TSWV that can infect other ornamentals and cultivated crops, because TSWV has a very broad host range (2). Elaborate inspections for TSWV and other viruses are necessary for production of healthy B. suaveolens, since the popularity and economic importance of this ornamental plant is increasing. To our knowledge, this is the first report of TSWV in B. suaveolens in Korea. References: (1) Anonymous. OEPP/EPPO Bull. 34:271, 2004. (2) G. Parrella et al. J. Plant Pathol. 85:227, 2003. (3) B.-N. Chung et al. Plant Pathol. J. 28:87, 2012. (4) K. Tamura et al. Mol. Biol. Evol. 28:2731, 2011.

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First Report of Tobacco rattle virus Associated with Corky Ringspot in Potatoes Grown in North Dakota

Plant Disease ◽

10.1094/pdis-94-1-0130b ◽

2010 ◽

Vol 94 (1) ◽

pp. 130-130 ◽

Cited By ~ 6

Author(s):

N. David ◽

I. Mallik ◽

N. C. Gudmestad

Keyword(s):

North Dakota ◽

Consensus Sequence ◽

Tobacco Rattle Virus ◽

Alfalfa Mosaic Virus ◽

Rna Isolation ◽

Rt Pcr ◽

Total Rna ◽

First Report ◽

Tuber Necrosis ◽

Corky Ringspot

Tobacco rattle virus (TRV) belongs to the genus Tobravirus and causes a stem mottle of potato (Solanum tuberosum) foliage and necrotic arcs and rings in tubers referred to as corky ringspot. This virus is generally transmitted by a number of species of stubby-root nematode. The virus is widespread and has been reported in California, Colorado, Florida, Idaho, Michigan, Oregon, Washington, Minnesota, and Wisconsin (2). In the spring of 2009, we received potato tubers of cv. Russet Burbank with internal necrotic arcs very similar to those caused by TRV from potato storages located in Grand Forks and Dickey counties of North Dakota. Total RNA was extracted from the necrotic lesions of two tubers from each location using the Total RNA Isolation kit (Promega Corp., Madison WI). These extracts were tested for TRV by reverse transcription (RT)-PCR using primers complementary to nucleotides 6555 to 6575 (Primer A) and identical to nucleotides 6113 to 6132 (Primer B) within the 3′ terminus of TRV-SYM RNA-1 (GenBank Accession No. X06172) (3). The expected 463-bp amplicons from two separate tuber samples from each county were cloned (TOPO Cloning; Invitrogen, Carlsbad, CA) and sequenced. The sequences obtained from the four clones at both locations were found to be identical to each other and were 99% identical to the corresponding regions of TRV isolates from Michigan and Florida (GenBank Accession Nos. EU315226.1 and AF055912.1, respectively). Since sequences from all four clones were identical, only one of the sequences was submitted to Genbank (Accession No. GQ223114) and thus represents a consensus sequence. The extracts also tested positive in RT-PCR with a second set of primers corresponding to sequences in TRV RNA-2 yielding a 3.8-kbp amplicon (1). No evidence was found by RT-PCR for several other viruses that cause tuber necrosis in potato (Potato mop top virus, Tomato spotted wilt virus, Alfalfa mosaic virus, and tuber necrosis strains of Potato virus Y). The virus was mechanically transmitted by inoculating sap from symptomatic tubers from both counties to tobacco cv. Samsun NN, which showed typical bright yellow patches and spots on leaves 2 weeks postinoculation. TRV was confirmed in tobacco by RT-PCR from total RNA extracted from tobacco leaves with both sets of the aforementioned primers. To our knowledge, this is the first report of TRV in North Dakota and the first report of corky ringspot disease of potato in this state. References: (1) J. M. Crosslin et al. Virus Res. 96:99, 2003. (2) N. C. Gudmestad et al. Plant Dis. 92:1254, 2008. (3) D. J. Robinson. J. Virol. Methods 40:57, 1992.

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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 Tomato spotted wilt virus on Pepper in Montenegro

Plant Disease ◽

10.1094/pdis-03-11-0167 ◽

2011 ◽

Vol 95 (7) ◽

pp. 882-882 ◽

Cited By ~ 5

Author(s):

J. Zindović ◽

A. Bulajić ◽

B. Krstić ◽

M. Ciuffo ◽

P. Margaria ◽

...

Keyword(s):

Amino Acid ◽

Tomato Spotted Wilt Virus ◽

Nucleotide Identity ◽

N Gene ◽

Rt Pcr ◽

First Report ◽

Tomato Spotted Wilt ◽

Italian Isolate ◽

Negative Controls ◽

Wilt Virus

In April 2009, chlorotic and necrotic ring spots, chlorotic line patterns, and stunting were observed on greenhouse-grown pepper plants in the vicinity of Podgorica, Montenegro. Disease symptom incidence was estimated at 40%. Symptomatic leaves were tested for the presence of Tomato spotted wilt virus (TSWV) with a commercial double-antibody sandwich (DAS)-ELISA diagnostic kit (Bioreba AG, Reinach, Switzerland). Commercial positive and negative controls were included in each ELISA. TSWV was detected serologically in 33 of 75 pepper samples. The virus was mechanically transmitted from ELISA-positive pepper samples to Nicotiana tabacum cv. Samsun using chilled 0.05 M phosphate buffer (pH 7) containing 0.1% sodium sulfite (1). Inoculated test plants produced chlorotic and necrotic concentric rings and necrotic spots, consistent with symptoms caused by TSWV on N. tabacum. For further confirmation of TSWV infection, reverse transcription (RT)-PCR was performed with the One-Step RT-PCR Kit (Qiagen, Hilden, Germany) using three sets of primers: S70-for/S890-rev (2) and S574-for/S1433-rev (3), both specific to the nonstructural (NSs) gene; and S1983-for/S2767-rev (2), specific to the nucleocapsid protein (N) gene. Total RNAs from naturally infected pepper and symptomatic N. tabacum cv. Samsun plants were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany). Total RNAs obtained from the Italian isolate of TSWV (GenBank Accession No. DQ398945) and healthy tobacco plants were used as positive and negative controls, respectively. The expected sizes of the RT-PCR products (820, 859, and 784 bp) were amplified from symptomatic pepper samples but not from healthy tissues. The PCR product obtained from isolate Is-344 using primers specific to N gene was purified by a QIAquick PCR Purification Kit (Qiagen), cloned into the pGEM-T Easy Vector (Promega, Madison, WI) and sequenced in both directions using the same primer pair as in RT-PCR. The sequences amplified with the two primer pairs specific to the NSs gene were obtained by direct sequencing (Bio-Fab Research Srl, Pomezia, Italy) and joined using MEGA4 software. Sequence analysis of the complete N gene (777 bp; GenBank Accession No. GU369717) revealed that the TSWV isolate originating from Montenegro shared 98.2 to 99.7% nucleotide identity (98.1 to 100% amino acid identities) with corresponding TSWV sequences deposited in GenBank. The Montenegrin isolate Is-344 was most closely related to Italian isolates from tomato (GU369725) and eggplant (GU369720). The partial (1,257 bp) nucleotide sequence of NSs gene (GU369737) showed 96 to 99.8% nucleotide identity (96.9 to 100% amino acid identity) with previously reported TSWV sequences, and in this case the highest identity was with French isolates from tomato (FR692835) and lettuce (FR692831). To our knowledge, this is the first report on the occurrence of TSWV in Montenegro. Data of this study sheds light on the importance of further survey studies and inspections of TSWV-susceptible crops cultivated in Montenegro. References: (1) Anonymous. OEPP/EPPO Bull. 29:465, 1999. (2) W. P. Qiu et al. Virology 244:186, 1998. (3) M. Tsompana et al. Mol. Ecol. 14:53, 2005.

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