Comparison of ELISA and RT-PCR assays for the detection of Tomato spotted wilt virus in peanut

Abstract Diagnosis of Tomato spotted wilt virus (TSWV) in peanut can be accomplished by enzyme-linked immunosorbent assay (ELISA) or reverse transcription polymerase chain reaction (RT-PCR) but there has been no report of a direct comparison of the success of the two assays in evaluating infection rates of field-grown peanut. We collected peanut root samples from field-grown plants, 76 in 2006 and 48 in 2007, and tested these samples by both ELISA and RT-PCR assays for the presence of TSWV. Out of 124 samples, 50 (40.3%) and 57 (46.0%) were positive for TSWV by ELISA and RT-PCR respectively. In 13.7% of these samples, ELISA and RT-PCR differed in their results. However, Chi square analysis showed no significant difference between the results for these two assays. This result supports the conclusion that ELISA and RT-PCR are comparable for detecting TSWV infection rates in field-grown peanuts.

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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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Tomato spotted wilt virus Identified in Desert Rose in Florida

Plant Disease ◽

10.1094/pd-89-0526c ◽

2005 ◽

Vol 89 (5) ◽

pp. 526-526 ◽

Cited By ~ 5

Author(s):

S. Adkins ◽

C. A. Baker

Keyword(s):

Tomato Spotted Wilt Virus ◽

The United States ◽

N Gene ◽

Enzyme Linked Immunosorbent Assay ◽

Insect Vector ◽

Rt Pcr ◽

Tomato Spotted Wilt ◽

Wilt Virus ◽

Symptomatic Plant ◽

Das Elisa

Desert rose (Adenium obesum (Forssk.) Roem. & Schult), a member of the family Apocynaceae, is characterized by fleshy stems and leaves and colorful flowers. This exotic ornamental, originally from southeast Africa, is propagated vegetatively and is a perennial in warm climates. Virus-like foliar symptoms, including chlorotic ring and line patterns, were observed in the fall of 2004 on one of five stock plants being maintained in a greenhouse in Fort Pierce, FL. Inclusion body morphology suggested the presence of a Tospovirus in the symptomatic plant, and Tomato spotted wilt virus (TSWV) was specifically identified in this plant using a commercially available double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA; Agdia, Elkhart, IN). TSWV was not detected in symptomless desert rose plants nor was Impatiens necrotic spot virus detected in any of the plants using DAS-ELISA. Graft transmission of TSWV to other desert rose plants was successful. 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 of the symptomatic plant confirmed the diagnosis. Nucleotide and deduced amino acid sequences of a 579-bp region of the RT-PCR product were 95 to 99% and 95 to 100% identical, respectively, to TSWV N-gene sequences in GenBank. No product was amplified from symptomless plants. Since these 3-year-old plants were grown on-site from seed and only expressed symptoms 2 months following damage to the greenhouse by hurricanes Frances and Jeanne, it is likely that viruliferous thrips were introduced from local vegetable or ornamental production areas during or following the storms. To our knowledge, this is the first report of TSWV infection of desert rose in Florida, although TSWV was observed in this plant in Europe approximately 10 years ago (3,4). Because of the wide distribution of TSWV in the United States, the increasing popularity of desert rose, and the recent identification of Cucumber mosaic virus in this host (2), attention to sanitation and insect vector management is merited during desert rose propagation and production. References: (1) S. Adkins and E. N. Rosskopf. Plant Dis. 86:1310, 2002. (2) C. A. Baker et al. Plant Dis. 87:1007, 2003. (3) J. Mertelik et al. Acta Hortic. 432:368, 1996. (4) J. Th. J. Verhoeven and J. W. Roenhorst. Acta Hortic. 377:175, 1994.

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Outbreak of Tomato spotted wilt virus in Tomato in Kenya

Plant Disease ◽

10.1094/pdis.2001.85.10.1123b ◽

2001 ◽

Vol 85 (10) ◽

pp. 1123-1123 ◽

Cited By ~ 6

Author(s):

A. W. Wangai ◽

B. Mandal ◽

H. R. Pappu ◽

S. Kilonzo

Keyword(s):

Host Range ◽

Tomato Spotted Wilt Virus ◽

Virus Disease ◽

N Gene ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Tomato Spotted Wilt ◽

Wide Host Range ◽

Test Kit ◽

Wilt Virus

Tomato spotted wilt virus (TSWV) of the genus Tospovirus, family Bunyaviridae (1), causes an economically important virus disease in tomato in several parts of the world. The virus has a wide host range that includes numerous crops and weeds and is transmitted by at least seven species of thrips. Tomato crops in the Subukia, Bahati, and Kabazi areas of the Nakuru District in Kenya were affected by a disease suggestive of TSWV infection during the November 1999 to March 2000 tomato-growing season. Farmers reported up to 80% losses of their potential yields. Characteristic symptoms were noticed on fruits, especially when they were green. Distinct concentric rings on fruits, which later turned into brown, uneven ripening, were the most visible symptoms. Foliage did not develop pronounced symptoms, but mild bronzing was observed in a few cultivars. However, foliage senesced prematurely, starting with older leaves. Foliar symptoms were mistaken for blight infection, and as a result, excessive fungicides were applied that failed to manage the disease. To test for TSWV infection, tomato leaf samples collected from the fields were tested initially with a TSWV test kit (HortiTech, Horticulture Research International, Wellesbourne, UK), and the results were confirmed by double-antibody sandwich-enzyme-linked immunosorbent assay with antibodies from Agdia Inc. (Elkhart, IN). Further molecular characterization was done using reverse transcription-polymerase chain reaction (RT-PCR). Total RNA was extracted from symptomatic leaves of tomato cv. Money Maker using the RNeasy mini kit (Qiagen Inc., Valencia, CA). Using primers 5′ TTAAGC AAGTTCTGTGAG 3′ and 5′ ATGTCTAAGGTTAAGCTC 3′ specific to the nucleoprotein (N) gene of TSWV, the N gene was amplified by RT-PCR (2). A 777-bp product of the expected size was obtained from symptomatic plants, whereas no amplification was obtained from noninfected tomato. The PCR product was cloned into pGEM-T Easy (Promega, Madison, WI) and sequenced. A search of GenBank revealed a sequence identity of 95 to 99% with the N genes of known TSWV isolates. To our knowledge, this is the first report TSWV infection of tomato in Kenya. Considering its wide host range, future surveys should be directed toward estimating its incidence in tomato and other TSWV-susceptible crops, such as Irish potatoes, pepper, peanut (groundnut), beans, and a wide variety of ornamental cut flowers in Kenya. References: (1) J. W. Moyer. Tospoviruses (Bunyaviridae). Pages 1803–1807 in: Encyclopedia of Virology. A. Granoff and R. G. Webster, eds. Academic Press, San Diego, CA, 1999. (2) Jain et al. Plant Dis. 82:900, 1998.

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First Report of Vidalia Onion (Allium cepa) Naturally Infected with Tomato spotted wilt virus and Iris yellow spot virus (Family Bunyaviridae, Genus Tospovirus) in Georgia

Plant Disease ◽

10.1094/pdis.2004.88.11.1285b ◽

2004 ◽

Vol 88 (11) ◽

pp. 1285-1285 ◽

Cited By ~ 19

Author(s):

S. W. Mullis ◽

D. B. Langston ◽

R. D. Gitaitis ◽

J. L. Sherwood ◽

A. C. Csinos ◽

...

Keyword(s):

Tomato Spotted Wilt Virus ◽

Thrips Tabaci ◽

Iris Yellow Spot Virus ◽

Yellow Spot ◽

Unknown Etiology ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Spot Virus ◽

Tomato Spotted Wilt ◽

Wilt Virus

Vidalia onion is an important crop in Georgia's agriculture with worldwide recognition as a specialty vegetable. Vidalia onions are shortday, Granex-type sweet onions grown within a specific area of southeastern Georgia. Tomato spotted wilt virus (TSWV) has been endemic to Georgia crops for the past decade, but has gone undetected in Vidalia onions. Tobacco thrips (Frankliniella fusca) and Western flower thrips (Frankliniella occidentalis) are the primary vectors for TSWV in this region, and a number of plant species serve as reproductive reservoirs for the vector or virus. Iris yellow spot virus (IYSV), an emerging tospovirus that is potentially a devastating pathogen of onion, has been reported in many locations in the western United States (2,4). Thrips tabaci is the known vector for IYSV, but it is unknown if noncrop plants play a role in its epidemiology in Georgia. During October 2003, a small (n = 12) sampling of onions with chlorosis and dieback of unknown etiology from the Vidalia region was screened for a variety of viruses, and TSWV and IYSV infections were serologically detected. Since that time, leaf and bulb tissues from 4,424 onion samples were screened for TSWV and IYSV using double antibody sandwich-enzyme linked immunosorbent assay (DAS-ELISA) with commercial kits (Agdia Inc., Elkhart, IN). Samples were collected from 53 locations in the Vidalia region during the growing season between November 2003 and March 2004. Plants exhibiting stress, such as tip dieback, necrotic lesions, chlorosis or environmental damage were selected. Of these, 306 were positive for TSWV and 396 were positive for IYSV using positive threshold absorbance of three times the average plus two standard deviations of healthy negative onion controls. Positive serological findings of the onion tissues were verified by immunocapture-reverse transcription-polymerase chain reaction (IC-RT-PCR) for TSWV (3) and RT-PCR for IYSV (1). In both instances, a region of the viral nucleocapsid (N) gene was amplified. The PCR products were analyzed with gel electrophoresis with an ethidium bromide stain in 0.8% agarose. Eighty-six percent (n = 263) of the TSWV ELISA-positive samples exhibited the expected 774-bp product and 55 percent (n = 217) of the IYSV ELISA-positive samples exhibited the expected 962-bp product. The reduced success of the IYSV verification could be attributed to the age and deteriorated condition of the samples at the time of amplification. Thrips tabaci were obtained from onion seedbeds and cull piles within the early sampling (n = 84) and screened for TSWV by the use of an indirect-ELISA to the nonstructural (NSs) protein of TSWV. Of the thrips sampled, 25 were positive in ELISA. While the incidence of IYSV and TSWV in the Vidalia onion crop has been documented, more research is needed to illuminate their potential danger to Vidalia onions. References: (1) I. Cortês et al. Phytopathology 88:1276, 1998. (2) L. J. du Toit et al. Plant Dis. 88:222, 2004. (3) R. K. Jain et al. Plant Dis. 82:900, 1998. (4) J. W. Moyer et al. (Abstr.) Phytopathology 93(suppl.):S115, 2003.

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Evaluation of peanut genotypes for resistance to Tomato spotted wilt virus by mechanical and thrips inoculation

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2006000600006 ◽

2006 ◽

Vol 41 (6) ◽

pp. 937-942 ◽

Cited By ~ 8

Author(s):

Luciana Cordeiro do Nascimento ◽

Viboon Pensuk ◽

Nivânia Pereira da Costa ◽

Francisco Miguel de Assis Filho ◽

Gilvan Pio-Ribeiro ◽

...

Keyword(s):

Tomato Spotted Wilt Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Mechanical Inoculation ◽

Rt Pcr ◽

Chain Reaction ◽

Breeding Lines ◽

Tomato Spotted Wilt ◽

Ic 10 ◽

Polymerase Chain ◽

Wilt Virus

The objective of this work was to evaluate the reactions of three peanut breeding lines (IC-10, IC-34, and ICGV 86388) to Tomato spotted wilt virus (TSWV) by mechanical and thrips inoculation, under greenhouse conditions, and compare them to the reactions of cultivars SunOleic, Georgia Green, and the breeding line C11-2-39. TSWV infection by mechanical inoculation was visually assessed using an index ranging from 0 (no symptoms) to 4 (apical death). Enzyme-linked immunosorbent assay was used to confirm TSWV infection from both mechanical and thrips inoculations. IC-10, IC-34, ICGV 86388, and C11-2-39 were more resistant than the cultivars SunOleic and Georgia Green based on mechanical inoculation. Upon thrips inoculation only IC-34 and ICGV-86388 were infected by TSWV, as demonstrated by reverse transcription polymerase chain reaction (RT-PCR), although no symptoms of infection were observed. The peanut breeding lines IC-10, IC-34, and ICGV 86388 show higher level of resistance to TSWV than cultivar Georgia Green considered a standard for TSWV resistance.

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Pittosporum tobira: A New Host for Tomato spotted wilt virus

Plant Disease ◽

10.1094/pdis.2000.84.4.491d ◽

2000 ◽

Vol 84 (4) ◽

pp. 491-491 ◽

Cited By ~ 3

Author(s):

A. Gera ◽

A. Kritzman ◽

J. Cohen

Keyword(s):

Tomato Spotted Wilt Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

New Host ◽

Thin Sections ◽

Nucleocapsid Gene ◽

Tomato Spotted Wilt ◽

Pcr Product ◽

Wilt Virus ◽

Pittosporum Tobira

In July 1998, Pittosporum tobira shrubs, grown in a nursery in the Sharon Valley of Israel, developed foliar ring spots, mild mosaic, and tip necrosis. Of 15 samples tested for the presence of Tomato spotted wilt virus (TSWV) with a commercially available enzyme-linked immunosorbent assay (ELISA) kit (Loewe Biochemica, Otterfing, Germany), 14 were positive for TSWV. Virus in crude sap extracted from symptomatic tissue was mechanically transmitted to Emilia spp., Petunia hybrida, Nicotiana glutinosa, N. benthamiana, and N. rustica plants, which developed symptoms characteristic of TSWV infection (1). ELISA tests of leaf sap extracted from naturally infected P. tobira and mechanically inoculated indicator plants gave a strong positive reaction to TSWV. Leaf samples of P. tobira were analyzed by transmission electron microscopy in leaf-dip preparations and thin sections of leaf tissues. Virus particles typical of a tospovirus were observed only in samples taken from symptomatic leaves. Primers specific to the nucleocapsid gene of TSWV were used in a reverse transcription-polymerase chain reaction (RT-PCR) assay to verify the presence of TSWV. RT-PCR gave an expected PCR product of ≈850 bp. The amplicon was cloned in the pGEM-T vector, and the recombinant clone was sequenced. The sequence of the cloned PCR product confirmed the identity of TSWV, verifying TSWV infection of P. tobira. This is the first report of infection of P. tobira by TSWV. Reference: (1) Y. Antignus et al. Phytoparasitica 25:319, 1997.

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First Report of Pinaceae in Georgia Naturally Infected with Tomato spotted wilt virus

Plant Disease ◽

10.1094/pd-90-0376b ◽

2006 ◽

Vol 90 (3) ◽

pp. 376-376 ◽

Cited By ~ 2

Author(s):

S. W. Mullis ◽

A. S. Csinos ◽

R. D. Gitaitis ◽

N. Martinez-Ochoa

Keyword(s):

Tomato Spotted Wilt Virus ◽

Pinus Elliottii ◽

Enzyme Linked Immunosorbent Assay ◽

Rt Pcr ◽

Total Rna ◽

Tomato Spotted Wilt ◽

Pine Trees ◽

Southern Georgia ◽

Wilt Virus ◽

Das Elisa

In October 2004, three pine tree seedlings included in an ongoing survey of annual weeds elicited positive reactions for Tomato spotted wilt virus (TSWV [family Bunyaviridae, genus Tospovirus]) using double assay sandwich-enzyme linked immunosorbent assay (DAS-ELISA) (Agdia Inc. Elkhart, IN). All the seedlings appeared healthy with no visible adverse effects from the virus. Over the next 12 months, an additional 1,326 samples of various pine species representing different growth stages were screened for TSWV. Samples were comprised of local populations of Pinus elliottii Engelm., P. taeda L., and P. palustris P. Mill., with the majority (n = 886) of samples being seedlings collected from southern Georgia. Along with the seedlings, needles, stem sections, and roots from saplings, as well as needles from mature trees, were screened for the virus. Of the trees sampled, 5.35% (n = 71) tested positive for TSWV, and of the seedlings 6.77% (n = 60) tested positive. The DAS-ELISA positive threshold was obtained using a figure of three times the average plus two standard deviations of healthy negative pine tissue control absorbance readings at 405 nm. A number of saplings testing positive (n = 6) were marked for further evaluation, and the needles from these saplings consistently screened positive for TSWV in subsequent testing. Furthermore, several samples were processed in modified burlese funnels to detect the possible presence of thrips. No thrips were ever identified in any of the burlese funnel collections. Different tissue types (needles, roots, stem sections, and reproductive organs) were screened, but the virus was only detected in needles. This suggests that local infections are only at feeding sites of viruliferous thrips. The known thrips vectors for TSWV are not considered to be pine feeders, and there is no indication that pine trees are a reproductive reservoir for any local thrips species. However, pine-feeding thrips may also feed on known weed hosts, thus pines could be a perennial reservoir. Mechanical inoculations from surface-sterilized infected pine needles onto known TSWV indicator plants (Nicotiana glutinosa L., N. benthamiana, and Emilia sonchifolia L. (DC)) were inconsistent. Successful transmission occurred 24% of the time. To further verify serological data, total RNA extracts of pine sap were purified and subjected to immunocapture-reverse transcriptase-polymerase chain reaction (IC-RT-PCR) using primers specific to the nucleocapsid gene of TSWV (1). IC-RT-PCR was used due to the inability to obtain useful total RNA from the pine tissues. This may be due to a secondary metabolite interfering with the total RNA extraction protocol. The IC-RT-PCR products were analyzed with electrophoresis using 0.01% ethidium bromide stain in a 0.8% agarose gel. Amplicons produced at the expected size (bp = 774) were considered positive for TSWV. Several were sequenced and were consistent with known, local TSWV isolates. There is no indication that TSWV is detrimental to pine trees, but considering the widespread distribution of the genus Pinus and the potential of serving as a reservoir of TSWV, it may play a role in the overall epidemiology of TSWV in southern Georgia. Reference: (1) R. K. Jain et al. Plant Dis. 82:900, 1998.

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First Report of Tomato spotted wilt virus in Habanero and Tabasco Peppers in Florida

Plant Disease ◽

10.1094/pdis.2000.84.10.1154c ◽

2000 ◽

Vol 84 (10) ◽

pp. 1154-1154 ◽

Cited By ~ 6

Author(s):

M. T. Momol ◽

H. R. Pappu ◽

W. Dankers ◽

J. R. Rich ◽

S. M. Olson

Keyword(s):

Tomato Spotted Wilt Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Coding Region ◽

Rt Pcr ◽

First Report ◽

Nucleocapsid Gene ◽

Tomato Spotted Wilt ◽

Habanero Pepper ◽

Stem Lesions ◽

Wilt Virus

In spring 2000, symptoms similar to thrips-vectored spotted wilt disease caused by Tomato spotted wilt virus (TSWV) were observed on habanero (Capsicum chinense) and tabasco (Capsicum frutescens) peppers in north Florida. Habanero peppers were from commercial fields grown for specialty markets and tabasco peppers were from research plots. Symptoms observed were leaf necrosis, fruit drop, necrotic stem lesions, and stunting. Fruit symptoms included chlorotic and necrotic spotting and distinct ring pattern and distortion. The incidence of symptomatic habanero peppers was 7 to 8% in one of the three production fields visited, and a lower incidence in two other fields (all in Jackson County). In tabasco pepper, TSWV was detected in spring and fall 1999, and spring 2000 seasons in 10 to 15% of the plants (Gadsden County). Adjacent tomato fields contained scattered plants exhibiting symptoms of TSWV. Diagnosis of TSWV from symptomatic stems, leaves, and fruit of habanero and tabasco peppers was confirmed by a double antibody sandwich enzyme linked immunosorbent assay (ELISA) using a commercially available kit (Agdia Inc., Elkhart, IN). ELISA values ranged from 1.57 to 1.95 for habanero pepper and 0.80 to 0.95 for tabasco pepper. The mean ELISA value of the negative controls was 0.001. To further verify TSWV infection, immunocapture reverse transcription-polymerase chain reaction (IC-RT-PCR) was performed (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 produces approximately 800 bp PCR product (1). IC-RT-PCR gave a single DNA band of expected size in both habanero and tabasco samples, while no amplification was found in an uninfected pepper sample. This is the first report of TSWV on habanero and tabasco peppers in Florida. TSWV continues to be an economically important disease constraint to the production of tomato, pepper (C. annuum), peanut, and tobacco in the southeastern United States (observations from Georgia and Florida). Meanwhile, the known host range is expanding to include new species of cultivated vegetables. References: (1) R. K. Jain et al.. Plant Dis. 82:900, 1998.

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Caracterização do Tomato chlorotic spot virus isolado de jiló no Vale do Paraíba, Estado de São Paulo

Fitopatologia Brasileira ◽

10.1590/s0100-41582002000300008 ◽

2002 ◽

Vol 27 (3) ◽

pp. 285-291 ◽

Cited By ~ 9

Author(s):

MARCELO EIRAS ◽

ALEXANDRE L. R. CHAVES ◽

ADDOLORATA COLARICCIO ◽

RICARDO HARAKAVA ◽

JANSEN DE ARAUJO ◽

...

Keyword(s):

Tomato Spotted Wilt Virus ◽

Sao Paulo ◽

Ringspot Virus ◽

São Paulo ◽

Rt Pcr ◽

Spot Virus ◽

Chlorotic Spot ◽

Tomato Spotted Wilt ◽

Wilt Virus ◽

Das Elisa

Os tospovírus são responsáveis por perdas significativas em diversas culturas, principalmente solanáceas. No município de São José dos Campos (SP), plantas de jiló (Solanum gilo) apresentando sintomas de mosaico, bolhosidades, nanismo e queda acentuada da produção foram coletadas para análise. Visando a caracterização do agente causador dos sintomas, testes biológicos, elétrono microscópicos, sorológicos e moleculares foram realizados. Através de inoculação mecânica em plantas indicadoras das famílias Amaranthaceae, Chenopodiaceae e Solanaceae obtiveram-se resultados típicos aos esperados para tospovírus. Ao microscópio eletrônico de transmissão, observaram-se, em contrastação negativa, partículas pleomórficas com diâmetro entre 80 e 110 nm e em cortes ultra-finos partículas presentes em vesículas do retículo endoplasmático. Através de DAS-ELISA, identificou-se o Tomato chlorotic spot virus (TCSV). A partir de RNA total extraído de folhas infetadas, amplificaram-se, via RT-PCR, fragmentos correspondentes ao gene da proteína do capsídeo (cp) os quais foram seqüenciados e comparados com outros depositados no "GenBank". A homologia de nucleotídeos e aminoácidos deduzidos foi respectivamente de 99 e 95% quando comparada com seqüências de isolados de TCSV. A comparação com as outras espécies do gênero Tospovirus apresentou valores de homologia entre 72 e 84%. Estes resultados confirmam a identidade deste vírus como pertencente à espécie TCSV, que é predominante no Estado de São Paulo e importante patógeno de outras plantas cultivadas. Além disso, variedades de jiló quando inoculadas foram susceptíveis tanto ao TCSV como às espécies Tomato spotted wilt virus (TSWV) e Groundnut ringspot virus (GRSV).

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