First Report of Lettuce big-vein associated virus (Varicosavirus) Infecting Lettuce in Mexico

Lettuce (Lactuca sativa) is a common consumed vegetable and a major source of income and nutrition for small farmers in Mexico. This crop is infected with at least nine viruses: Mirafiori lettuce big-vein virus (MiLBVV), Lettuce big-vein associated virus (LBVaV), both transmitted by the soil-borne fungus Olpidium brassicae; Tomato spotted wilt virus (TSWV), Tomato chlorotic spot virus (TCSV), Groundnut ringspot virus (GRSV), Lettuce mottle virus (LMoV), Cucumber mosaic virus (CMV), Bidens mosaic virus (BiMV), and Lettuce mosaic virus (LMV) (1). From March to May 2012, a disease on lettuce was observed in the south region of Mexico City displaying mild to severe mosaic, leaf deformation, reduced growth, slight thickening of the main vein, and plant death. At the beginning of the epidemic there were just a few plants with visible symptoms and 7 days later the entire crop was affected, causing a loss of 93% of the plants. It was estimated by counting the number of severely affected or dead plants in three plots. No thrips, aphids, or whiteflies were observed in the crop during this time. Twenty plants with similar symptoms were collected and tested by RT-PCR using the primers LBVaVF 5′-AACACTATGGGCATCCACAT-3′ and LBVaVR 5′-GCATGTCAGCAATCAGAGGA-3′ specific for the coat protein gene of LBVaV, amplifying a 322-bp fragment. Primers CP829F 5′-CCWACTTCATCAGTTGAGCGCTG-3′ and CP1418R 5′-TATCAGCTCCCTACACTATCCTCGC-3′ were used to detect MiLBVV (2). No amplification was obtained for MiLBVaV in any plants tested. PCR products of approximately 300 bp were obtained from four out of 20 symptomatic lettuce samples tested for LBVaV, but not from healthy plant and water controls. These results suggest the presence of another virus in symptomatic lettuce plants. Amplicons were gel-purified and sequenced using LBVaVF and LBVaVR primers. A consensus sequence was generated using the Bioedit v. 5 program. Both sequences of these Mexican lettuce isolates were 100% identical (Accession Nos. KC776266.1 and KC776267.1) and had identities between 94 and 99% to all sequences of LBVaV available in GenBank. Additionally, when alignments were made using ClustalW, these sequences showed identities of 99.7% to Almeria-Spanish isolate (Accession No. AY581686.1); 99.4% to Granada-Spanish isolate (AY581689.1); 99.1% to Dutch isolate (JN710441.1), Iranian isolate (JN400921.1), Australian isolate (GU220725.1), Brazilian isolate (DQ530354.1), England isolate (AY581690.1), and American isolate (AY496053.1); 96.2% to Australian isolate (GU220722.1); 96.3% to Japanese isolate (AB190527.1); and 92.8% to Murcia-Spanish isolate (AY581691.1). Twenty lettuce plants were mechanically inoculated with leaf tissue taken from the four plants collected in the field and tested positive for LBVaV by RT-PCR; 12 days after inoculation, mosaic symptoms were observed in all inoculated plants and six of them were analyzed individually by RT-PCR obtaining a fragment of the expected size. To our knowledge, this is the first report of LBVaV infecting lettuce in Mexico. Further surveys and monitoring of LBVaV incidence and distribution in the region, vector competence of olpidium species, and impact on the crop quality are in progress. References: (1) P. M. Agenor et al. Plant Viruses 2:35, 2008. (2) R. J. Hayes et al. Plant Dis. 90:233, 2006.

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

Plant Disease ◽

10.1094/pdis-92-8-1254b ◽

2008 ◽

Vol 92 (8) ◽

pp. 1254-1254 ◽

Cited By ~ 7

Author(s):

T. Tian ◽

H.-Y. Liu ◽

S. T. Koike

Keyword(s):

Mosaic Virus ◽

Consensus Sequence ◽

Amino Acid Sequences ◽

Apium Graveolens ◽

Petroselinum Crispum ◽

Rt Pcr ◽

First Report ◽

Virus Particles ◽

Pcr Products ◽

Reverse Primer

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

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First Report of Alfalfa mosaic virus Infecting Basil (Ocimum basilicum) in California

Plant Disease ◽

10.1094/pdis-06-11-0516 ◽

2012 ◽

Vol 96 (2) ◽

pp. 295-295 ◽

Cited By ~ 3

Author(s):

W. M. Wintermantel ◽

E. T. Natwick

Keyword(s):

Nucleic Acid ◽

Mosaic Virus ◽

Alfalfa Mosaic Virus ◽

Plant Viruses ◽

Ocimum Basilicum ◽

Mechanical Transmission ◽

Rt Pcr ◽

Imperial Valley ◽

First Report ◽

Production Region

Basil (Ocimum basilicum L.) plants collected from three fields in Imperial County, CA in May, 2011 were found to be exhibiting yellowing, chlorotic sectors and spots on leaves, resulting in unmarketable plants. Dodder (Cuscuta spp.) was present in one of the fields, but was not visibly associated with symptomatic plants. Total nucleic acid was extracted from four symptomatic and three asymptomatic basil plants, as well as from the dodder plant with the RNeasy Plant Mini Kit (Qiagen, Valencia, CA). Nucleic acid extracts were tested by reverse transcription (RT)-PCR for the presence of Alfalfa mosaic virus (AMV) using primers designed to amplify a 350-nt region of the AMV coat protein gene (3). RT-PCR produced bands of the expected size in extracts from all symptomatic plants and the dodder sample. No amplification was obtained from symptomless plants. A 350-nt band amplified from one plant was gel-extracted, sequenced (TACGen, Richmond, CA), and confirmed to be AMV by comparison to sequences available in GenBank (Accession No. K02703). Although serological tests on an initial basil sample were negative for AMV by ELISA using antiserum produced against AMV by R. Larsen, USDA-ARS, Prosser, WA (unpublished), AMV was confirmed by ELISA and RT-PCR in symptomatic Nicotiana benthamiana, N. clevelandii, and Malva parviflora plants following mechanical transmission from basil source plants. The fields with AMV infections were located at opposite ends of the production region from one another, indicating widespread dispersal of AMV in the region. All AMV positive plants were adjacent to alfalfa. Two additional basil plantings in shade houses open to the outside environment did not have AMV symptomatic plants and were also confirmed negative by RT-PCR, but these plantings were at the extreme north end of Imperial Valley agriculture and well away from any alfalfa fields. At the time the basil plantations were sampled for AMV, no aphids were found in any plantations, but during the several weeks prior to finding the AMV-positive plants, cowpea aphid, Aphis craccivora Koch; pea aphid, Acyrthosiphon pisum Harris; blue alfalfa aphid, Acyrthosiphon kondoi Shinji; and spotted alfalfa aphid, Therioaphis maculata Buckton were colonizing Imperial Valley alfalfa fields, producing winged adults. AMV is transmitted by at least 14 aphid species (1), and most aphid populations increase during the late spring in this important desert agricultural region. The acquisition of AMV by dodder suggests the parasitic plant may serve as a vector of AMV within basil fields, although further study will be necessary for clarification. Significant acreage of basil is grown in the Imperial Valley. This acreage is surrounded by extensive and increasing alfalfa production totaling 55,442 ha (137,000 acres) in Imperial County and representing a 21% increase in acreage over 2009 for the same region (2). To our knowledge, this is the first report of basil infected by AMV in California. The proximity of basil production to such a large alfalfa production region warrants the need for enhanced efforts at aphid management in basil production to reduce vector populations and reduce transmission to basil crops. References: (1) E. M. Jaspars and L. Bos. Alfalfa mosaic virus. No. 229 in: Descriptions of Plant Viruses. Commonw. Mycol. Inst./Assoc. Appl. Biol., Kew, England, 1980. (2) C. Valenzuela. Imperial County California Crop and Livestock Report, 2010. (3) H. Xu and J. Nie. Phytopathology 96:1237, 2006.

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First Report of Tobacco mild green mosaic virus Infecting Capsicum annuum in Tunisia

Plant Disease ◽

10.1094/pdis-93-7-0761b ◽

2009 ◽

Vol 93 (7) ◽

pp. 761-761 ◽

Cited By ~ 5

Author(s):

M. I. Font ◽

M. C. Córdoba-Sellés ◽

M. C. Cebrián ◽

J. A. Herrera-Vásquez ◽

A. Alfaro-Fernández ◽

...

Keyword(s):

Mosaic Virus ◽

Capsicum Annuum ◽

Polyclonal Antibodies ◽

Plant Viruses ◽

Mottle Virus ◽

Tomato Mosaic Virus ◽

Rt Pcr ◽

Tomato Plants ◽

First Report ◽

Pepper Plants

During the springs of 2007 and 2008, leaf deformations as well as symptoms of mild green and chlorotic mosaic were observed on pepper (Capsicum annuum) plants grown in Monastir (northwest Tunisia) and Kebili (southeast Tunisia). With the support of projects A/5269/06 and A/8584/07 from the Spanish Agency for International Cooperation (AECI), symptomatic leaf samples were analyzed by transmission electron microscopy (TEM) of leaf-dip preparations. Typical tobamovirus-like particles (rigid rods ≈300 nm long) were observed in crude plant extracts. According to literature, at least six tobamoviruses infect peppers: Paprika mild mottle virus (PaMMV); Pepper mild mottle virus (PMMoV); Ribgrass mosaic virus (RMV); Tobacco mild green mosaic virus (TMGMV); Tobacco mosaic virus (TMV); and Tomato mosaic virus (ToMV) (1). Extracts from six symptomatic plants from Monastir and four from Kebili fields tested negative for ToMV, TMV, and PMMoV and tested positive for TMGMV by double-antibody sandwich (DAS)-ELISA using polyclonal antibodies specific to each virus (Loewe Biochemica GMBH, Sauerlach, Germany). To confirm the positive TMGMV results, total RNAs from 10 symptomatic plants that tested positive by ELISA were extracted and analyzed by reverse transcription (RT)-PCR using primers designed to specifically amplify a region of the coat protein gene (CP) of TMGMV (2). The 524-bp TMGMV-CP specific DNA fragment was amplified from all samples, but was not amplified from healthy plants or the sterile water used with negative controls. RT-PCR products were purified and directly sequenced. BLAST analysis of the obtained sequence (GenBank No. EU770626) showed 99 to 98% nucleotide identity with TMGMV isolates PAN-1, DSMZ PV-0113, TMGMV-Pt, and VZ1 (GenBank Nos. EU934035, EF469769, AM262165, and DQ460731, respectively) and less than 69% with PaMMV and PMMoV isolates (GenBank Nos. X72586 and AF103777, respectively). Two TMGMV-positive, singly, infected symptomatic pepper plants collected from Monastir and Kebili were used in mechanical transmissions to new pepper and tomato plants. Inoculated pepper plants exhibited mild chlorosis symptoms and tested positive for TMGMV only; however, inoculated tomato plants cv. Marmande were asymptomatic and tested negative as expected for TMGMV infection (1). To our knowledge, although C. annuum has been shown as a natural host for TMGMV (2), this is the first report of TMGMV in Tunisia. Reference: (1) A. A. Brunt et al. Plant Viruses Online: Descriptions and Lists from the VIDE Database. Version: 20th August 1996. Online publication, 1996. (2) J. Cohen et al. Ann. Appl. Biol. 138:153, 2001.

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First Report of Alfalfa mosaic virus Infecting Tedera (Bituminaria bituminosa (L.) C.H. Stirton var. albomarginata and crassiuscula) in Australia

Plant Disease ◽

10.1094/pdis-04-12-0378-pdn ◽

2012 ◽

Vol 96 (9) ◽

pp. 1384-1384 ◽

Cited By ~ 5

Author(s):

R. A. C. Jones ◽

D. Real ◽

S. J. Vincent ◽

B. E. Gajda ◽

B. A. Coutts

Keyword(s):

Mosaic Virus ◽

Alfalfa Mosaic Virus ◽

Plant Viruses ◽

Yellow Mosaic Virus ◽

Rt Pcr ◽

First Report ◽

Pasture Legumes ◽

Bituminaria Bituminosa ◽

Pcr Products ◽

Burr Medic

Tedera (Bituminaria bituminosa (L.) C.H. Stirton vars albomarginata and crassiuscula) is being established as a perennial pasture legume in southwest Australia because of its drought tolerance and ability to persist well during the dry summer and autumn period. Calico (bright yellow mosaic) leaf symptoms occurred on occasional tedera plants growing in genetic evaluation plots containing spaced plants at Newdegate in 2007 and Buntine in 2010. Alfalfa mosaic virus (AlMV) infection was suspected as it often causes calico in infected plants (1,2) and infects perennial pasture legumes in local pastures (1,3). Because AlMV frequently infects Medicago sativa (alfalfa) in Australia and its seed stocks are commonly infected (1,3), M. sativa buffer rows were likely sources for spread by aphids to healthy tedera plants. When leaf samples from plants with typical calico symptoms from Newdegate (2007) and Buntine (2010) were tested by ELISA using poyclonal antisera to AlMV, Bean yellow mosaic virus (BYMV) and Cucumber mosaic virus (CMV), only AlMV was detected. When leaf samples from 864 asymptomatic spaced plants belonging to 34 tedera accessions growing at Newdegate and Mount Barker in 2010 were tested by ELISA, no AlMV, BYMV, or CMV were detected, despite presence of M. sativa buffer rows. A culture of AlMV isolate EW was maintained by serial planting of infected seed of M. polymorpha L. (burr medic) and selecting seed-infected seedlings (1,3). Ten plants each of 61 accessions from the local tedera breeding program were grown at 20°C in an insect-proof air conditioned glasshouse. They were inoculated by rubbing leaves with infective sap containing AlMV-EW or healthy sap (five plants each) using Celite abrasive. Inoculations were always done two to three times to the same plants. When both inoculated and tip leaf samples from each plant were tested by ELISA, AlMV was detected in 52 of 305 AlMV-inoculated plants belonging to 36 of 61 accessions. Inoculated leaves developed local necrotic or chlorotic spots or blotches, or symptomless infection. Systemic invasion was detected in 20 plants from 12 accessions. Koch's postulates were fulfilled in 12 plants from nine accessions (1 to 2 of 5 plants each), obvious calico symptoms developing in uninoculated leaves, and AlMV being detected in symptomatic samples by ELISA, inoculation of sap to diagnostic indicator hosts (2) and RT-PCR with AlMV CP gene primers. Direct RT-PCR products were sequenced and lodged in GenBank. When complete nucleotide CP sequences (666 nt) of two isolates from symptomatic tedera samples and two from alfalfa (Aq-JX112758, Hu-JX112759) were compared with that of AlMV-EW, those from tedera and EW were identical (JX112757) but had 99.1 to 99.2% identities to the alfalfa isolates. JX112757 had 99.4% identity with Italian tomato isolate Y09110. Systemically infected tedera foliage sometimes also developed vein clearing, mosaic, necrotic spotting, leaf deformation, leaf downcurling, or chlorosis. Later-formed leaves sometimes recovered, but plant growth was often stunted. No infection was detected in the 305 plants inoculated with healthy sap. To our knowledge, this is the first report of AlMV infecting tedera in Australia or elsewhere. References: (1) B. A. Coutts and R. A. C. Jones. Ann. Appl. Biol. 140:37, 2002. (2) E. M. J. Jaspars and L. Bos. Association of Applied Biologists, Descriptions of Plant Viruses No. 229, 1980. (3) R. A. C. Jones. Aust. J. Agric. Res. 55:757, 2004.

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First Report of a Lettuce-Infecting Sequivirus in Chile

Plant Disease ◽

10.1094/pd-89-1129a ◽

2005 ◽

Vol 89 (10) ◽

pp. 1129-1129 ◽

Cited By ~ 3

Author(s):

R. Krause-Sakate ◽

A. S. Jadão ◽

A. C. Firmino ◽

M. A. Pavan ◽

F. M. Zerbini ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Mosaic Virus ◽

Plant Viruses ◽

Yellow Mosaic Virus ◽

Mixed Infections ◽

Replicase Gene ◽

Rt Pcr ◽

Chain Reaction ◽

First Report ◽

Polymerase Chain

Sequiviruses are isometric aphidborne plant viruses. Dandelion yellow mosaic virus (DaYMV), genus Sequivirus, was isolated from dandelion and lettuce in Europe. Lettuce mottle virus (LeMoV), a putative sequivirus, is often found in mixed infections with Lettuce mosaic virus (LMV) in Brazil (3). DaYMV, LeMoV and LMV cause similar mosaics in field-grown lettuce. Differences in biology and sequence suggest that DaYMV and LeMoV are distinct species (2). Forty-two and 101 lettuce samples with mosaic symptoms collected from two locations near Santiago during a survey of lettuce viruses in Chile in 2002 and 2003, respectively, were analyzed for the presence of LeMoV using reverse transcription polymerase chain reaction (RT-PCR). Total RNA was extracted (1) and used for RT-PCR with the specific LeMoV primers pairs Lmo3 (5′ ACATGAGCACTAGTGAGG 3′) and Lmo4 (5′ AGATAGAGCCGTCT GGCG 3′) (2). One of the 42 and three of the 101 samples produced the expected 300-bp fragment. Isometric particles of 30 nm diameter, typical of a sequivirus, were visualized by transmission electron microscopy. These samples were tested using RT-PCR for the presence of LMV and Cucumber mosaic virus (CMV), but no mixed infections were observed. One isolate, Ch36, was reamplified with the degenerate primer pairs DALE 1 (5′ GARTTCAACATGCACGCCAG 3′) and DALE 2 (5′ TTTTTCTCCCCATYCGTCAT 3′) which amplify part of the putative replicase gene (2) and produced a 563-bp fragment that was cloned on pGEM-T Easy (Promega, Madison, WI) and sequenced. The Ch36 product (EMBL Accession No. AM039965) showed 97% amino acid identity with LeMoV from Brazil, 79% with DaYMV, 72% with the sequivirus Parsnip yellow fleck virus, and 34% with the waikavirus Maize chlorotic dwarf virus. To our knowledge, this is the first report of a sequivirus in field lettuce in Chile, and although the virus was found at low incidence, this report extends the range of LeMoV to the western side of the Cordillera de Los Andes. The impact of LeMoV needs to be further analyzed in Chile, Brazil, and possibly other South American countries. References: (1) Y. D. Bertheau et al. DNA amplification by polymerase chain reaction (PCR) 1998. In: Methods for the Detection and Quantification of Erwinia carotovora subsp. atroseptica on potatoes. M. C. N. Perombelon and J. M. van der Wolff, eds. Scott. Crop Res. Inst. Occasional Publ., Dundee, 1998. (2) A. S. Jadão. Caracterização parcial e desenvolvimento de oligonucleotídeos específicos para detecção de sequivirus infectando alface. Ph.D. thesis. FCA-UNESP-Botucatu, Brazil, 2004. (3) O. Stangarlin et al. Plant Dis. 84:490, 2000.

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First Report of Tomato torrado virus Infecting Tomato in Single and Mixed Infections with Cucumber mosaic virus in Panama

Plant Disease ◽

10.1094/pdis-93-2-0198a ◽

2009 ◽

Vol 93 (2) ◽

pp. 198-198 ◽

Cited By ~ 20

Author(s):

J. A. Herrera-Vásquez ◽

A. Alfaro-Fernández ◽

M. C. Córdoba-Sellés ◽

M. C. Cebrián ◽

M. I. Font ◽

...

Keyword(s):

Coat Protein ◽

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Potato Virus ◽

Plant Viruses ◽

Tomato Mosaic Virus ◽

Rt Pcr ◽

Tomato Production ◽

Related Sequence ◽

First Report

In February of 2008, in open-field-grown tomato crops (Solanum lycopersicum L.) from the central regions of Coclé, Herrera, Los Santos, and Veraguas of Panama, unusual disease symptoms, including deformation, necrosis, purple margins, interveinal yellowing, downward and upward curling of the leaflets alternately, necrotic lines in sepals and branches, fruits distorted with necrotic lines on the surface, and severe stunting, were observed. Tomato production was seriously damaged. To verify the identity of the disease, five symptomatic tomato plants from four fields of these regions were selected and analyzed by double-antibody sandwich (DAS)-ELISA using specific antibodies to Cucumber mosaic virus (CMV), Potato virus X (PVX), Potato virus Y (PVY), Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV) (Loewe Biochemica, Sauerlach, Germany), and Pepino mosaic virus (PepMV) (DSMZ, Braunschweig, Germany). Total RNA was extracted from all plants and tested using reverse transcription (RT)-PCR with three pairs of specific primers: one pair designed to amplify 586 bp of the coat protein gene of CMV (CMV-F 5′-CCTCCGCGGATGCTAACTT-3′ and CMV-R 5′-CGGAATCAGACTGGGAGCA-3′) and the other two pairs to Tomato torrado virus (ToTV) that amplify 580 and 574 bp of the polyprotein (4) and coat protein (Vp23) (3) region of RNA2, respectively; and by dot-blot hybridization with a digoxygenin-labeled RNA probe complementary to the aforementioned polyprotein. The serological analysis for PVX, PVY, ToMV, TSWV, and PepMV were negative. ToTV was detected in all samples analyzed. Three of these samples were also positive for CMV by serological and molecular analysis. No differences in symptom expression were observed between plants infected with both viruses or with ToTV alone. RT-PCR products were purified and directly sequenced. BLAST analysis of one CMV sequence (GenBank Accession No. EU934036) showed 98% identity with a CMV sequence from Brazil (most closely related sequence) (GenBank Accession No. AY380812) and 97% with the Fny isolate (CMV subgroup I) (GenBank Accession No. U20668). Two ToTV sequences were obtained (GenBank Accession Nos. EU934037 and FJ357161) and showed 99% and 98% identities with the polyprotein and coat protein region of ToTV from Spain (GenBank Accession No. DQ388880), respectively. CMV is transmitted by aphids and is distributed worldwide with a wide host range (2), while ToTV is transmitted by whiteflies and has only been reported in tomato crops in Spain and Poland and recently on weeds in Spain (1). To our knowledge, this is the first time ToTV has been detected in Panama and the first report of CMV/ToTV mixed infection. References: (1) A. Alfaro-Fernández et al. Plant Dis. 92:831, 2008. (2) A. A. Brunt et al. Plant Viruses Online: Descriptions and Lists from the VIDE Database. Online Publication, 1996. (3) H. Pospieszny et al. Plant Dis. 91:1364, 2007. (4) M. Verbeek et al. Arch. Virol. 152:881, 2007.

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First Report of Tomato torrado virus in Tomato Crops in France

Plant Disease ◽

10.1094/pdis-93-12-1352c ◽

2009 ◽

Vol 93 (12) ◽

pp. 1352-1352 ◽

Cited By ~ 14

Author(s):

E. Verdin ◽

P. Gognalons ◽

C. Wipf-Scheibel ◽

I. Bornard ◽

G. Ridray ◽

...

Keyword(s):

Mosaic Virus ◽

Sandwich Elisa ◽

Trialeurodes Vaporariorum ◽

World Intellectual Property Organization ◽

Tomato Mosaic Virus ◽

Healthy Plant ◽

Rt Pcr ◽

Tomato Plants ◽

First Report ◽

Test Plants

In June 2008, tomato (Solanum lycopersicum L.) plants cv. Fer De Lance (De Ruiter Seeds, Bergschenhoek, the Netherlands) grown in greenhouses near Perpignan (southern France) showed growth reduction and necrotic lesions on fruits, stems, and basal parts of the leaves. Tomato torrado virus (ToTV) was suspected on the basis of symptoms and its recent description in Spain (4). Primer set A (3), designed to ToTV RNA-2, was used for reverse transcription (RT)-PCR experiments on RNA extracted from four infected plants and allowed the amplification of a 493-bp fragment. No amplification was observed from healthy plant extracts. The RT-PCR product was directly sequenced (GQ303330) and a BLAST search in GenBank revealed 99.8- and 99.5%-nt identity with Polish (EU563947) and Spanish type strain (DQ388880) isolates of ToTV, respectively. Double-antibody sandwich-ELISA tests were conducted on these four samples to check for the presence of other viruses commonly found in tomato crops in France. Tomato spotted wilt virus, Parietaria mottle virus, Cucumber mosaic virus, Tomato mosaic virus, and Potato virus Y were not detected but Pepino mosaic virus (PepMV) was detected in all samples. ToTV was mechanically transmitted to Physalis floridana but PepMV was not. This plant was used to inoculate healthy tomatoes that served as a ToTV source for further experiments. Mechanical inoculation to test plants showed that Nicotiana benthamiana, N. clevelandii, N. debneyi, N. glutinosa, Capsicum annuum, Solanum melongena, and some tomato cultivars (including Fer De Lance), in which typical necrotic symptoms were observed, were systemically infected by the virus. Isometric particles ~28 nm in diameter were observed by electron microscopy in crude extracts of infected plants negatively stained with 1% ammonium molybdate, pH 7. To confirm ToTV identification, whitefly transmission experiments were performed with Trialeurodes vaporariorum and Bemisia tabaci. Adult whiteflies were placed in cages with infected tomato plants for 1-, 24-, or 48-h acquisition access periods (AAP) before transferring them by groups of ~50 on susceptible tomato plantlets placed under small containers (six plants per AAP). Forty-eight hours later, plants were treated with an insecticide and transferred to an insect-proof containment growth room. Ten days later, RNA preparation from all plants was tested by RT-PCR for the presence of ToTV. No transmission was observed with a 1-h AAP. With a 24-h AAP, transmission to four of six test plants was observed with both whitefly species, while at 48 h, AAP transmission to three and four plants of six was observed with T. vaporariorum and B. tabaci, respectively. Noninoculated control plants were all negative by RT-PCR. These experiments confirm T. vaporariorum and B. tabaci as natural vectors of ToTV as previously described (1,2). ToTV has been already reported in Spain, Poland, Hungary, and Australia, but to our knowledge, this is the first report of ToTV in France. Our detection of ToTV in April 2009 from the same area revealed 7 positive tomato plants of 17 tested. This observation suggests the persistence of the disease in the Perpignan Region. References: (1) K. Amari et al. Plant Dis. 92:1139, 2008. (2) H. Pospieszny et al. Plant Dis. 91:1364, 2007 (3) J. Van der Heuvel et al. Plant Virus Designated Tomato Torrado Virus. Online publication. World Intellectual Property Organization WO/2006/085749, 2006. (4) M. Verbeek et al. Arch. Virol. 152:881, 2007.

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First Report of Cucumber mosaic virus on Jatropha curcas in India

Plant Disease ◽

10.1094/pdis-92-1-0171c ◽

2008 ◽

Vol 92 (1) ◽

pp. 171-171 ◽

Cited By ~ 16

Author(s):

S. K. Raj ◽

S. Kumar ◽

S. K. Snehi ◽

U. Pathre

Keyword(s):

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Jatropha Curcas ◽

Leaf Tissue ◽

Mosaic Disease ◽

Biodiesel Fuel ◽

Rt Pcr ◽

Specific Primers ◽

First Report ◽

Gel Diffusion

Jatropha curcas L. is a major commercial biodiesel fuel crop grown on 98 million acres (39.66 million ha) in India. Severe mosaic disease accompanied by yellow spots was noticed on 15% of J. curcas growing in the experimental plots of NBRI, Lucknow, India, during October of 2006. Inoculations with sap from symptomatic plants resulted in systemic mosaic on three of seven J. curcas seedlings. Gel diffusion tests were performed with antiserum to Cucumber mosaic virus (CMV), Tobacco ringspot virus, and Chrysanthemum virus B (PVAS-242a, PVAS-157, and PVAS-349, respectively; ATCC, Manassas, VA). Leaf sap of infected plants reacted only with PVAS-242a, indicating the presence of CMV. Reverse transcription (RT)-PCR assays with CMV coat protein gene specific primers (Genbank Accession Nos. AM180922 and AM180923) and total nucleic acid extracted from symptomatic J. curcas leaf tissue yielded the expected ~650-bp amplicon, which was cloned and sequenced (GenBank Accession No. EF153739). BLAST analysis indicated 98 to 99% nucleotide identity with CMV isolates (GenBank Accession Nos. DQ914877, DQ640743, AF350450, AF281864, X89652, AF198622, DQ152254, DQ141675, and DQ028777). Phylogenetic analysis showed that the J. curcas isolate was more closely related to Indian isolates of CMV belonging to subgroup Ib. Literature surveys revealed records of Jatropha mosaic virus on J. gossypiifolia in Puerto Rico (1) and on J. curcas in India (2). To our knowledge, this is the first report of CMV on J. curcas. References: (1) J. K. Brown et al. Arch. Virol. 146:1581, 2001. (2) D. S. A. Narayana et al. Curr. Sci. 91:584, 2006.

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First Report of Apple mosaic virus in Alaska

Plant Disease ◽

10.1094/pdis-08-11-0707 ◽

2012 ◽

Vol 96 (3) ◽

pp. 463-463 ◽

Cited By ~ 1

Author(s):

N. L. Robertson

Keyword(s):

Mosaic Virus ◽

Plant Material ◽

Direct Sequencing ◽

Sandwich Elisa ◽

Plant Viruses ◽

Apple Orchard ◽

Tween 20 ◽

Rt Pcr ◽

Apple Trees ◽

First Report

Apple mosaic virus (ApMV; family Bromoviridae, genus Ilarvirus) is one of the oldest and most economically important viruses of apples (Malus × domestica Borkh.) (1,3). Yield losses may vary from negligible to as much as 50%, depending on the affected cultivar. Although ApMV is found worldwide and occurs naturally in more than 65 plant species (1), it has not been reported to occur in Alaska. In July 2011, noticeably bright yellow mosaic leaves were observed on apple ‘Valentine’ and its rootstalk ‘Ranetka’ from an apple orchard in Wasilla, AK. Leaves were collected and assayed by reverse transcription (RT)-PCR using ApMV-specific primers (2) and total RNA extracted with buffer modifications to RNeasy Plant Mini Kit (Qiagen, Valencia, CA). Briefly, 50 mg of leaf tissue was ground in liquid nitrogen and 450 μl of SE buffer (0.14 M NaCl, 2 mM KCl, 2 mM KH2PO4, 8 mM Na2HPO4·2H2O [pH 7.4], 0.05% vol/vol Tween-20, 2% wt/vol polyvinylpyrrolidone 40, 0.2% wt/vol ovalbumin, 0.5% wt/vol bovine serum albumin, and 0.05% wt/vol sodium azide) was added, and after vigorous vortexing, 80 μl of the mixture was added to 400 μl of RLT buffer supplied by the kit and then processed as directed by the manufacturer (4). Direct sequencing of the predicted ~260-bp PCR product resulted in 97 to 98% nucleotide identities to ApMV accessions in GenBank when analyzed by BLAST. To determine the distribution and incidence of infection in the Wasilla orchard, all 118 apple trees (99 cultivars) were then sampled and assayed serologically by double-antibody sandwich-ELISA with ApMV antiserum according to the manufacturer's protocol (Agdia, Inc., Elkhart, IN). Apple ‘Geneva Early’ and the same ‘Valentine’ tree and its rootstock tested positive for ApMV by ELISA and RT-PCR. Strong diagnostic ApMV symptoms were not apparent on the infected ‘Geneva Early’, which is typical for most commercially grown apples. No leaves were available on the ‘Ranetka' rootstock of ApMV-infected ‘Geneva Early’ for virus indexing. An additional 21 apple trees with no symptoms from an orchard in Talkeetna, AK tested negative to ApMV by ELISA. Limited natural spread of ApMV to other plants may be by pollen and seed transmission. The most prevalent mode of transmission is from ApMV-infected rootstock and grafts. It is important to obtain new propagation plant material from certified virus tested nurseries and to avoid grafting plant material containing ApMV. To my knowledge, this is the first report of ApMV in Alaska. References: (1) R. W. Fulton. No. 83. CMI/AAB Descriptions of Plant Viruses. 1972. (2) W. Menzel et al. J. Virol. Methods 99:81, 2002. (3) M. J. Roossinck et al. Virus Taxonomy. Eight Report of the International Committee on Taxonomy of Viruses, 1049, 2005. (4) J. Thompson et al. J. Virol. Methods 111:85, 2003.

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First Report of Catharanthus mosaic virus in Mandevilla in the United States

Plant Disease ◽

10.1094/pdis-09-14-0913-pdn ◽

2015 ◽

Vol 99 (1) ◽

pp. 165-165 ◽

Cited By ~ 4

Author(s):

D. Mollov ◽

M. A. Guaragna ◽

B. Lockhart ◽

J. A. M. Rezende ◽

R. Jordan

Keyword(s):

United States ◽

Amino Acid ◽

Mosaic Virus ◽

Consensus Sequence ◽

The United States ◽

Amino Acid Sequences ◽

Universal Primers ◽

Rt Pcr ◽

First Report ◽

Virus Particles

Mandevilla (Apocynaceae) is an ornamental tropical vine popular for its bright and attractive flowers. During 2012 to 2013, 12 Mandevilla sp. samples from Minnesota and Florida nurseries were submitted for analysis at the University of Minnesota Plant Disease Clinic. Plants showed mosaic symptoms, leaf deformation, premature leaf senescence, and vine dieback. Filamentous virus particles with modal lengths 700 to 900 nm were observed by transmission electron microscopy (TEM) in partially purified preparations from symptomatic leaves. Partially purified virions were obtained using 30% sucrose cushion centrifuged at 109,000 gmax for 2 h at 10°C (5). No other virus particles were observed in these samples, nor were any observed in non-symptomatic samples. One sample was submitted as potted plant (Mandevilla ‘Sunmandeho’ Sun Parasol Giant White) and was kept under greenhouse conditions for subsequent analyses. Total RNA (Qiagen) was extracted from this sample, and Potyvirus was detected using the universal primers Poty S (5′-GGN AAY AAY AGY GGN CAR CC-3′) and PV1 (5′-20(T)V-3′) (1) by reverse transcription (RT)-PCR (3). The amplified product was the expected ~1.7-kb, corresponding to the partial nuclear inclusion body gene, the coat protein (CP) gene, and the 3′ end untranslated region. The RT-PCR amplicon was cloned (NEB) and sequenced, and the 1,720-bp consensus sequence was deposited in GenBank (Accession No. KM243928). NCBI BLAST analysis at the nucleotide level revealed highest identity (83%) with an isolate of Catharanthus mosaic virus (CatMV) from Brazil (Accession No. DQ365928). Pairwise analysis of the predicted 256 amino acid CP revealed 91% identity with the CatMV Brazilian isolate (ABI94824) and 68% or less identity with other potyviruses. Two potyviruses are usually considered the same species if their CP amino acid sequences are greater than 80% identical (2). Serological analysis of the infected sample Mandevilla ‘Sunmandeho’ Sun Parasol Giant White using a CatMV specific antiserum (4) resulted in positive indirect ELISA reactions. CatMV has been previously reported in periwinkle (Catharanthus roseus) in Brazil (4). Based on the analyses by TEM, RT-PCR, nucleotide and amino acid sequence identities, and serological reactivity, we identify this virus as a U.S. Mandevilla isolate of CatMV. To our knowledge, this is the first report of Catharanthus mosaic virus both in the United States and in Mandevilla. References: (1) J. Chen et al. Arch Virol. 146:757, 2001. (2) A. Gibbs and K. Ohshima. Ann. Rev. Phytopathol. 48:205, 2010. (3) R. L. Jordan et al. Acta Hortic. 901:159, 2011. (4) S. C. Maciell et al. Sci. Agric. Piracicaba, Brazil. 68:687, 2011. (5) D. Mollov et al. Arch Virol. 158:1917, 2013.

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