scholarly journals First Report of Tomato torrado virus Infecting Tomato in Italy

Plant Disease ◽  
2010 ◽  
Vol 94 (9) ◽  
pp. 1172-1172 ◽  
Author(s):  
S. Davino ◽  
L. Bivona ◽  
G. Iacono ◽  
M. Davino

In 2009 and 2010, approximately 2% of plants had disease symptoms, including initial leaflet chlorosis that later developed into necrotic spots and general necroses along the leaflet. Fruit production on affected plants was substantially reduced and necroses were also present. Total RNA was extracted from five symptomatic plant samples using the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany) and analyzed by reverse transcription (RT)-PCR with specific primer pair: TR2F (5′ GAAGGACGAAGAGCGACTG 3′), and TR2R (5′ AAGGTAGGTATGCGTTTGC 3′) (1). The primers amplified a 575-bp fragment within the coat protein Vp23 of Tomato torrado virus (ToTV). No RT-PCR products were observed when water or asymptomatic tomato plants were used as controls. The RT-PCR products were purified and directly sequenced in both directions. Pair-wise similarity analysis confirmed the presence of ToTV with 99% similarity to isolate PRI-ToTV0301 (GenBank Accession No. DQ388880) and 98% similarity to isolate Kra (Accession No. EU652402). A representative sequence was deposited with GenBank (Accession No. GU903899). To further confirm the presence of ToTV, dsRNA analysis was conducted on all five symptomatic plants and one healthy tomato plant (2). Electrophoresis of dsRNA showed two bands of approximately 5,400 and 7,800 nucleotides long, typical of ToTV in all samples, while a third band between the other two (approximately 6,400 nt) was detected. Serological testing using double-antibody sandwich-ELISA was also conducted on the five symptomatic and 25 additional plants from the same greenhouse that displayed typical Pepino mosaic virus (PepMV) symptoms only. Antibodies used for serological testing screened for the presence of PepMV, Tomato spotted wilt virus, Cucumber mosaic virus, and Tomato mosaic virus (Loewe Biochemica, Sauerlach, Germany). These tests detected PepMV in all samples with disease symptoms typical of PepMV, and in three of the five samples with the newly described symptoms. To our knowledge, this is the first report of ToTV in Italy, and in some plants, co-infection with PepMV was likely. All ToTV-infected tomato plants in the greenhouse were destroyed. References: (1) H. Pospieszny et al. Plant Dis. 91:1364, 2007. (2) J. Sambrook et al. Molecular Cloning. A Laboratory Manual. 2nd ed. Cold Spring Harbor Laboratory Press, Woodbury, NY, 1989.

Plant Disease ◽  
2009 ◽  
Vol 93 (12) ◽  
pp. 1352-1352 ◽  
Author(s):  
E. Verdin ◽  
P. Gognalons ◽  
C. Wipf-Scheibel ◽  
I. Bornard ◽  
G. Ridray ◽  
...  

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.


Plant Disease ◽  
2021 ◽  
Author(s):  
Ahmed Sabra ◽  
Mohammed Ali Al Saleh ◽  
I. M. Alshahwan ◽  
Mahmoud A. Amer

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


Plant Disease ◽  
2009 ◽  
Vol 93 (7) ◽  
pp. 761-761 ◽  
Author(s):  
M. I. Font ◽  
M. C. Córdoba-Sellés ◽  
M. C. Cebrián ◽  
J. A. Herrera-Vásquez ◽  
A. Alfaro-Fernández ◽  
...  

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.


Plant Disease ◽  
2009 ◽  
Vol 93 (5) ◽  
pp. 554-554 ◽  
Author(s):  
A. Alfaro-Fernández ◽  
G. Bese ◽  
C. Córdoba-Sellés ◽  
M. C. Cebrián ◽  
J. A. Herrera-Vásquez ◽  
...  

During the growing seasons of 2007 and 2008, in commercial greenhouses of tomato crops (Solanum lycopersicum L.) located in Szeged, Öcsöd, and Csongrád (southeastern regions of Hungary), unusual disease symptoms were observed, including necrotic spots in defined areas at the base of the leaflet, necrosis in the stems, and necrotic lines on the fruits surface. Affected plants appeared inside the greenhouses with a random distribution and the incidence recorded was at least 40%. These symptoms resembled those described for Tomato torrado virus (ToTV) infection in Spain (1) and Poland (3). To verify the identity of the disease, three symptomatic plants from commercial greenhouses of each geographic location were selected and analyzed by double-antibody sandwich-ELISA using polyclonal antibodies specific to Cucumber mosaic virus (CMV), 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 and tested by reverse transcription (RT)-PCR with three pair of specific primers: one pair used to amplify the coat protein (CP) gene of PepMV (2) and the other two pairs specific to ToTV that amplify 580 bp of the polyprotein (4) and a fragment of 574 bp in the CP Vp23 (3). Nonisotopic dot-blot hybridization using a digoxygenin-labeled RNA probe complementary to the aforementioned fragment of the polyprotein was also performed. Tomato samples were negative for all the viruses tested by serological analysis and for PepMV by RT-PCR. However, all three samples were positive for ToTV by molecular hybridization and RT-PCR. RT-PCR products were purified and directly sequenced. The amplified fragments of the three Hungarian isolates, ToTV-H1, ToTV-H2, and ToTV-H3, for the polyprotein (GenBank Accession Nos. EU835496, FJ616995, and FJ616994, respectively) and the CP Vp23 (GenBank Accession Nos. FJ616996, FJ616997, and FJ616998, respectively) showed 99 to 98% nt identity with the polyprotein and the coat protein regions of ToTV from Spain and Poland (GenBank Accession Nos. DQ3888880 and EU563947, respectively). Whiteflies, commonly found in Hungarian greenhouses, have been reported to transmit ToTV (3), although the efficiency of transmission is unknown. To our knowledge, this is the first report of ToTV in Hungary. References: (1) A. Alfaro-Fernández et al. Plant Dis. 91:1060, 2007. (2) I. Pagán et al. Phytopathology 96:274, 2006. (3) H. Pospieszny et al. Plant Dis. 91:1364, 2007. (4) J. Van der Heuvel et al. Plant Virus Designated Tomato Torrado Virus. Online publication. World Intellectual Property Organization. WO/2006/085749, 2006.


Plant Disease ◽  
2011 ◽  
Vol 95 (1) ◽  
pp. 78-78 ◽  
Author(s):  
K. E. Efthimiou ◽  
A. P. Gatsios ◽  
K. C. Aretakis ◽  
L. C. Papayiannis ◽  
N. I. Katis

Pepino mosaic virus (PepMV) (genus Potexvirus, family Flexiviridae) is a mechanically transmitted virus that has emerged as a significant problem of greenhouse tomato crops in Europe and around the world during the past 10 years (1). In spring of 2010, mosaic symptoms were observed on leaves of cherry tomato (Lycopersicon esculentum var. cerasiforme) greenhouse crops (hybrids Shiren, Tomito, and Rubino top) in the areas of Drymos and Vonitsa, located at Aitoloakarnania Prefecture, in Greece. A total of 63 tomato samples (55 from symptomatic and 8 from asymptomatic plants) were collected from 11 greenhouses where disease incidence ranged from 10 to 20%. All samples were tested by double-antibody sandwich (DAS)-ELISA using polyclonal antibodies from BIOREBA, AG (Reinach, Switzerland) for the presence of PepMV, Cucumber mosaic virus (CMV), and Tomato mosaic virus (ToMV). Leaf tissue from PepMV-, CMV-, and ToMV-infected samples and virus-free tomato plants were included in all tests as positive and negative controls, respectively. Results showed that 53 symptomatic samples collected from all greenhouses were infected with PepMV and two were co-infected with PepMV and CMV. Total RNA was extracted from all infected plants with a commercially available kit (Qiagen, Hilden, Germany) and amplified by conventional and real-time reverse transcription (RT)-PCR, using previously reported protocols (2). Positive and negative controls were also included in each assay. The 200-bp amplified PCR fragments of Triple Gene Block 3 (TGB3) obtained from five infected samples were purified and both strands were sequenced. Sequencing data were analyzed, deposited in the GenBank, and compared with other reported sequences. In addition, leaf tissue from five samples infected with only PepMV was used for mechanical inoculation of four plants of Nicotiana glutinosa, N. benthamiana, and tomato (L. esculentum FA 179 hybrid) plants. As negative controls, two plants from each species were used. Sequencing analysis showed that all five PepMV sequences were identical (GenBank Accession Nos. FR686904 to FR686908) and possessed 100% identity PepMVstrain CH2 (DQ000985). Inoculation results showed that the virus was successfully transmitted to N. benthamiana and tomato plants which developed mosaic symptoms, and tested positive by DAS-ELISA and RT-PCR. N. glutinosa plants did not develop any symptoms and were found to be free of PepMV when tested by DAS-ELISA and RT-PCR. To our knowledge, this is the first report of PepMV in Greece. Further studies on the disease prevalence and incidence and its economic impact on tomato production are required. PepMV is currently under quarantine status in the EU and therefore new protective measures should be recommended to prevent the spread of PepMV to other regions of Greece. References: (1) I. M. Hanssen and B. P. H. J. Thomma. Mol. Plant Pathol. 11:179, 2010. (2) K. S. Ling et al. J. Virol. Methods 144:65, 2007.


Plant Disease ◽  
2011 ◽  
Vol 95 (10) ◽  
pp. 1320-1320 ◽  
Author(s):  
C. Zou ◽  
J. Meng ◽  
Z. Li ◽  
M. Wei ◽  
J. Song ◽  
...  

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


Plant Disease ◽  
2007 ◽  
Vol 91 (9) ◽  
pp. 1204-1204 ◽  
Author(s):  
S. Adkins ◽  
G. McAvoy ◽  
E. N. Rosskopf

Red soda apple (Solanum capsicoides All.), a member of the Solanaceae, is a weed originally from Brazil (3). It is a perennial in southern Florida and is characterized by abundant prickles on stems, petioles, and leaves. Prickles on stems are more dense than those on its larger, noxious weed relative, tropical soda apple (Solanum viarum Dunal), and the mature red soda apple fruits are bright red in contrast to the yellow fruits of tropical soda apple (2). Virus-like foliar symptoms of light and dark green mosaic were observed on the leaves of a red soda apple in a Lee County cow pasture during a tropical soda apple survey during the fall of 2004. The appearance of necrotic local lesions following inoculation of Nicotiana tabacum cv. Xanthi nc with sap from the symptomatic red soda apple leaves suggested the presence of a tobamovirus. Tropical soda apple mosaic virus (TSAMV), a recently described tobamovirus isolated from tropical soda apple in Florida, was specifically identified by a double-antibody sandwich-ELISA (1). An additional six similarly symptomatic red soda apple plants were later collected in the Devils Garden area of Hendry County. Inoculation of N. tabacum cv. Xanthi nc with sap from each of these symptomatic plants also resulted in necrotic local lesions. Sequence analysis of the TSAMV coat protein (CP) gene amplified from total RNA by reverse transcription (RT)-PCR with a mixture of upstream (SolA5′CPv = 5′-GAACTTWCAGAAGMAGTYGTTGATGAGTT-3′; SolB5′CPv = 5′-GAACTCACTGARRMRGTTGTTGAKGAGTT-3′) and downstream (SolA3′CPvc = 5′-CCCTTCGATTTAAGTGGAGGGAAAAAC-3′; SolB3′CPvc = 5′-CGTTTMKATTYAAGTGGASGRAHAAMCACT-3′) degenerate primers flanking the CP gene of Solanaceae-infecting tobamoviruses confirmed the presence of TSAMV in all plants from both locations. Nucleotide and deduced amino acid sequences of the 483-bp CP gene were both 98 to 99% identical to the original TSAMV CP gene sequences in GenBank (Accession No. AY956381). TSAMV was previously identified in tropical soda apple in these two locations in Lee and Hendry counties and three other areas in Florida (1). Sequence analysis of the RT-PCR products also revealed the presence of Tomato mosaic virus in the plant from Lee County. To our knowledge, this represents the first report of natural TSAMV infection of any host other than tropical soda apple and suggests that TSAMV may be more widely distributed in solanaceous weeds than initially reported. References: (1) S. Adkins et al. Plant Dis. 91:287, 2007. (2) N. Coile. Fla. Dep. Agric. Consum. Serv. Div. Plant Ind. Bot. Circ. 27, 1993. (3) U.S. Dep. Agric., NRCS. The PLANTS Database. National Plant Data Center. Baton Rouge, LA. Published online, 2006.


Plant Disease ◽  
2012 ◽  
Vol 96 (4) ◽  
pp. 592-592 ◽  
Author(s):  
M. Verbeek ◽  
A. M. Dullemans

Tomato (Solanum lycopersicum L.) plants grown in plastic greenhouses near Villa de Leyva, northeast of Bogota, Colombia showed necrotic spots on the leaves in September 2008. Initial symptoms were necrosis beginning at the base of leaflets that were surrounded by yellow areas. These symptoms resembled those described for Tomato torrado virus (ToTV; family Secoviridae, genus Torradovirus), which was first found in Spain (2). Other (tentative) members of the genus Torradovirus, Tomato marchitez virus (ToMarV), Tomato chocolate spot virus (ToChSV), and Tomato chocolàte virus (ToChV) (3) induce similar symptoms on tomato plants. One sample, coded T418, was stored in the freezer and brought to our lab in 2011. Serological tests (double-antibody sandwich-ELISA) using polyclonal antibodies (Prime Diagnostics, Wageningen, The Netherlands) on leaf extracts showed the absence of Pepino mosaic virus (PepMV), Tobacco mosaic virus (TMV), Tomato spotted wilt virus (TSWV), Cucumber mosaic virus (CMV), Potato virus X (PVX), and Potato virus Y (PVY). Leaf extracts were mechanically inoculated onto the indicator plants Physalis floridana, Nicotiana hesperis ‘67A’, and N. occidentalis ‘P1’ (six plants in total) and were kept in a greenhouse at 20°C with 16 h of light. Necrotic symptoms appeared 4 to 5 days postinoculation and resembled those described for ToTV (2). Two dip preparations of systemically infected P. floridana and N. occidentalis leaves were examined by electron microscopy, which revealed the presence of spherical virus particles of approximately 30 nm. To confirm the presence of ToTV, total RNA was extracted from the original leaf material and an inoculated P. floridana and N. occidentalis plant using the Qiagen Plant Mini Kit (Qiagen, Hilden, Germany) following manufacturer's instructions. ToTV-specific primer sets ToTV-Dp33F/ToTV-Dp20R (5′-TGCTCAATGTTGGAAACCCC-3′/5′-AGCCCTTCATAGGCTAGCC-3′, amplifying a fragment of the RNA1 polyprotein with an expected size of 751 bp) and ToTV-Dp1F/ToTV-Dp2R (5′-ACAAGAGGAGCTTGACGAGG-3′/5′-AAAGGTAGTGTAATGGTCGG-3′, amplifying a fragment on the RNA2 movement protein region with an expected size of 568 bp) were used to amplify the indicated regions in a reverse transcription (RT)-PCR using the One-Step Access RT-PCR system (Promega, Madison, WI). Amplicons of the predicted size were obtained in all tested materials. The PCR products were purified with the Qiaquick PCR Purification Kit (Qiagen) and sequenced directly. BLAST analyses of the obtained sequences (GenBank Accession Nos. JQ314230 and JQ314229) confirmed the identity of isolate T418 as ToTV, with 99% identity to isolate PRI-ToTV0301 in both fragments (GenBank Accession Nos. DQ388879 and DQ388880 for RNA1 and RNA 2, respectively). To our knowledge, this is the first report of ToTV in Colombia, and interestingly, since ToTV has been found only in Europe and Australia (1) so far, this is the first report of ToTV on the American continent. References: (1) C. F. Gambley et al. Plant Dis. 94:486, 2010. (2) M. Verbeek et al. Arch. Virol. 152:881, 2007. (3) M. Verbeek et al. Arch. Virol. 155:751, 2010.


Plant Disease ◽  
2014 ◽  
Vol 98 (9) ◽  
pp. 1284-1284 ◽  
Author(s):  
G. Parrella ◽  
B. Greco

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


Plant Disease ◽  
2014 ◽  
Vol 98 (11) ◽  
pp. 1589-1589 ◽  
Author(s):  
F.-F. Zhao ◽  
D.-H. Xi ◽  
J. Liu ◽  
X.-G. Deng ◽  
H.-H. Lin

Chilli veinal mottle virus (ChiVMV), a potyvirus, is widespread over the world. In China, it was first reported in chili pepper (Capsicum annuum) in Hainan Province (south China) in 2006 (2). Subsequently, it was reported in tobacco (Nicotiana tabacum) in Yunnan Province (southwest China) in 2011 (1). Sichuan Province is one of the largest vegetable producing areas of China. In May 2012, tomatoes with leaves displaying virus-infected symptoms like mottling, mosaic, narrowing, or curling were observed in several fields of Chengdu, eastern Sichuan Province, southwest China. Of the 20 fields we investigated, four fields with 90% tomato plants were infected. During 2012 and 2013, six samples were collected from symptomatic tomato leaves based on different symptoms and locations. All six samples were assayed by western blotting using polyclonal antisera (Cucumber mosaic virus [CMV], Tobacco mosaic virus [TMV]) obtained from Agdia (Elkhart) and one antiserum to ChiVMV obtained from Yunnan Academy of Agricultural Science (China). Two samples from Pengzhou and one sample from Shuangliu exhibiting mosaic leaves were positive for TMV, one sample from Pixian exhibiting narrowing leaves was positive for CMV, and the other two samples from Shuangliu exhibiting mottle and leaf distortion were positive for ChiVMV. Total RNAs was extracted from all six samples and healthy tomato leaves using Trizol reagent (Invitrogen), First-strand cDNA synthesis primed with oligo(dT) by SuperScript III Reverse Transcriptase (Invitrogen). RT-PCR was performed using primer pairs ChiVMV-CP F (5′-GCAGGAGAGAGTGTTGATGCTG-3′) and ChiVMV–CP R (5′-(T)16AACGCCAACTATTG-3′), which were designed to direct the amplification of the entire capsid protein (CP) gene and 3′ untranslated region (3′-UTR) of ChiVMV (GenBank Accession No. KC711055). The expected 1,166-bp DNA fragment was amplified from the two tomato samples from Shuangliu that were positive for ChiVMV in the western blot tests, but not from the others. The obtained fragments were purified and cloned into the PMD18-T vector (TaKaRa) and sequenced. The sequencing results showed that the two ChiVMV isolates from tomato in Shuangliu were identical (KF738253). Nucleotide BLAST analysis revealed that this ChiVMV isolate shared ~84 to 99% nucleotide identities with other ChiVMV isolates available in GenBank (KC711055 to KF220408). To fulfill Koch's postulates, we isolated this virus by three cycle single lesion isolation in N. tabacum, and mechanically inoculated it onto tomato leaves. The same mottle and leaf distortion symptoms in systemic leaves were observed. Subsequent RT-PCR, fragment clone, and sequence determination tests were repeated and the results were the same. All the evidence from these tests revealed that the two tomato plants were infected by ChiVMV. To our knowledge, this is the first report of ChiVMV naturally infecting tomato in China. It shows that ChiVMV is spreading in China and is naturally infecting a new solanaceous crop in the southwest area, and the spread of the virus may affect tomato crop yields in China. Thus, it is very important to seek an effective way to control this virus. References: (1) M. Ding et al. Plant Dis. 95:357, 2011. (2) J. Wang et al. Plant Dis. 90:377, 2006.


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