scholarly journals Bidens mottle virus and Apium virus Y Identified in Ammi majus in Florida

Plant Disease ◽  
2008 ◽  
Vol 92 (6) ◽  
pp. 975-975 ◽  
Author(s):  
C. A. Baker ◽  
E. N. Rosskopf ◽  
M. S. Irey ◽  
L. Jones ◽  
S. Adkins

Ammi majus (bishop's weed), a member of the Apiaceae, is grown from seed for cut flowers in South Florida. In March 2005, plants were found to be showing virus-like symptoms including mosaic, vein clearing, and leaf rugosity (3) that rendered their flowers unmarketable. Inclusion morphology in epidermal strips from these infected plants indicated the presence of one or more potyviruses. This was confirmed by ELISA with commercially available antiserum for potyvirus identification (Agdia, Elkhart, IN). Clover yellow vein virus (ClYVV) was identified by sequencing and confirmed with specific antiserum (4). However, ClYVV was not identified in all potyvirus-infected samples from 2005, indicating the presence of one or more additional potyviruses. Bidens mottle virus (BiMoV) was subsequently identified in one of three potyvirus-infected samples by immunodiffusion tests using specific antiserum for BiMoV (Department of Plant Pathology, University of Florida), cylindrical inclusion morphology in epidermal strips, host range data, and sequencing of cloned reverse transcription (RT)-PCR products from degenerate potyvirus primers (2). Nucleotide and deduced amino acid sequences of a partial polyprotein gene sequence (GenBank Accession No. EU255631) were 95 and 98% identical, respectively, to a Florida isolate of BiMoV recently reported from tropical soda apple (1). Similar virus-like symptoms were again observed in A. majus in January 2007 and persisted through March. ELISA testing again indicated the presence of a potyvirus. However, neither ClYVV nor BiMoV were identified in the initial 2007 samples. Instead, sequence analysis of the cloned RT-PCR products amplified with degenerate potyvirus primers (2) from seven potyvirus-infected samples collected on two dates in January and one each in February and March revealed the presence of Apium virus Y (ApVY). The 3′ terminal portion of the genome (GenBank Accession No. EU255632) was found to be 90 to 91% identical to ApVY sequences in GenBank at the nucleotide level. Deduced amino acid sequences of the NIb and CP regions of these RT-PCR products were 96 and 95% identical, respectively, to ApVY sequences in GenBank. One of these seven ApVY-infected samples (collected in March 2007) was determined to be coinfected with BiMoV by sequence analysis of the cloned RT-PCR products. Six clones were sequenced. Three were determined to be ApVY as indicated above. Nucleotide and deduced amino acid sequences of a partial polyprotein gene sequence from the other three clones were 95 and 97% identical, respectively, to the 2005 A. majus BiMoV isolate. Although ClYVV and BiMoV have previously been reported in other hosts in Florida, to the best of our knowledge, this is the first report of BiMoV and ApVY in A. majus anywhere and the first report of ApVY in North America. References: (1.) C. A. Baker et al. Plant Dis. 91:905, 2007. (2.) A. Gibbs and A. J. Mackenzie. J. Virol. Methods 63:9, 1997. (3.) M. S. Irey et al. (Abstr.) Phytopathology (suppl.)95:S46, 2005. (4.) M. S. Irey et al. Plant Dis. 90:380, 2006.

Plant Disease ◽  
2011 ◽  
Vol 95 (10) ◽  
pp. 1319-1319 ◽  
Author(s):  
J. F. Zhou ◽  
G. P. Wang ◽  
R. F. Kuang ◽  
L. P. Wang ◽  
N. Hong

Cherry green ring mottle virus (CGRMV; a member of the genus Foveavirus in the family Flexiviridae) has a single-stranded, positive-sense RNA genome of approximately 8.4 kb (4). The viral infection on several Prunus spp. has been mainly reported in Japan, New Zealand, and some countries in Africa, Europe, and North America (3). The virus can cause leaf yellowing on sour and tart cherry. Sweet cherry plants are symptomless hosts of the virus. During the growing season of 2010, leaf samples were collected randomly from one ornamental cherry (Prunus serrulata L.) and 26 sweet cherry (P. avium (L.) L.) plants grown in Shangdong and Henan provinces in northern China and 64 peach (P. persica L. Batsch) plants grown in Hubei Province in central China and tested for the presence of CGRMV by reverse transcription (RT)-PCR. Total RNA was extracted from leaves using the CTAB protocol reported by Li et al (2). Primer set, CGRMV1/CGRMV2 (1), was used for the amplification of a 949-bp fragment, which contains the complete CP gene of 807 bp. PCR products with the expected size were identified in one ornamental cherry, seven sweet cherry, and eight peach plants. Although some of sampled plants showed leaf chlorosis, we did not find the specific association between the symptom and CGRMV infection. The obtained PCR products were cloned into the vector pMD18-T (TaKaRa, Dalian, China). Three independent clones from each isolate were sequenced by Genscript Corp., Nanjing, China. Results showed that CP sequences from the Chinese CGRMV isolates shared 87.7 to 99.8% nucleotide and 93.3 to 100% deduced amino acid similarities, and clones intra each isolate shared more than 99% nt similarities. The CP gene sequences of two representative isolates from cherry (YT-Ch-1) and peach (Pe-HB-18) were submitted to GenBank with Accession Nos. HQ539656 and JF810672, respectively. The neighbor-joining phylogenetic trees generated with nucleotide and amino acid sequences of CP genes by Clustal X v1.8 revealed that all Chinese CGRMV isolates fell into two well-resolved clades. Most of the Chinese CGRMV isolates (12 of 16 isolates, including the isolate YT-Ch-1) were grouped in a large clade represented by isolate ITA5 (GenBank Accession No. AF533159). Four isolates from peach (including the isolate Pe-HB-18) clustered into another clade represented by isolate ITA6 (GenBank Accession No. AF533160). In July 2010, peach GF305 seedlings were inoculated by side grafting with budwoods from two CGRMV positive cherry plants. In May 2011, some newly developed leaves from all inoculated plants showed vein yellowing. The CGRMV infection in these inoculated peach GF305 plants was detected by RT-PCR and protein A sandwich-ELISA using antiserum raised against the recombinant CP of CGRMV isolate YT-Ch-1 (unpublished data). These results further confirmed the CGRMV infection on field cherry plants as detected by RT-PCR. To our knowledge, this is the first record of the presence of CGRMV in ornamental and sweet cherry and peach plants in China, which provides valuable information for further evaluating the sanitary status of the virus in sweet cherry and peach orchards in China. References: (1) R. Li and R. Mock. J. Virol. Methods 129:162, 2005. (2) R. Li et al. J. Virol. Methods 154:48, 2008. (3) K. G. Parker et al. USDA. Agric. Handb. No. 437:193, 1976. (4) Y. Zhang et al. J. Gen. Virol. 79:2275, 1998.


Author(s):  
Katarzyna Trzmiel

AbstractBrome mosaic virus (BMV) and cocksfoot mottle virus (CfMV) are pathogens of grass species including all economically important cereals. Both viruses have been identified in Poland therefore they create a potential risk to cereal crops. In this study, a duplex—reverse transcription—polymerase chain reaction (duplex-RT-PCR) was developed and optimized for simultaneous detection and differentiation of BMV and CfMV as well as for confirmation of their co-infection. Selected primers CfMVdiag-F/CfMVdiag-R and BMV2-F/BMV2-R amplified 390 bp and 798 bp RT-PCR products within coat protein (CP) region of CfMV and replicase gene of BMV, respectively. Duplex-RT-PCR was successfully applied for the detection of CfMV-P1 and different Polish BMV isolates. Moreover, one sample was found to be co-infected with BMV-ML1 and CfMV-ML1 isolates. The specificity of generated RT-PCR products was verified by sequencing. Duplex-RT-PCR, like conventional RT-PCR, was able to detect two viruses occurring in plant tissues in very low concentration (as low as 4.5 pg/µL of total RNA). In contrast to existing methods, newly developed technique offers a significant time and cost-saving advantage. In conclusion, duplex-RT-PCR is a useful tool which can be implemented by phytosanitary services to rapid detection and differentiation of BMV and CfMV.


1980 ◽  
Vol 187 (3) ◽  
pp. 863-874 ◽  
Author(s):  
D M Johnson ◽  
J Gagnon ◽  
K B Reid

The serine esterase factor D of the complement system was purified from outdated human plasma with a yield of 20% of the initial haemolytic activity found in serum. This represented an approx. 60 000-fold purification. The final product was homogeneous as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (with an apparent mol.wt. of 24 000), its migration as a single component in a variety of fractionation procedures based on size and charge, and its N-terminal amino-acid-sequence analysis. The N-terminal amino acid sequence of the first 36 residues of the intact molecule was found to be homologous with the N-terminal amino acid sequences of the catalytic chains of other serine esterases. Factor D showed an especially strong homology (greater than 60% identity) with rat ‘group-specific protease’ [Woodbury, Katunuma, Kobayashi, Titani, & Neurath (1978) Biochemistry 17, 811-819] over the first 16 amino acid residues. This similarity is of interest since it is considered that both enzymes may be synthesized in their active, rather than zymogen, forms. The three major CNBr fragments of factor D, which had apparent mol.wts. of 15 800, 6600 and 1700, were purified and then aligned by N-terminal amino acid sequence analysis and amino acid analysis. By using factor D labelled with di-[1,3-14C]isopropylphosphofluoridate it was shown that the CNBr fragment of apparent mol.wt. 6600, which is located in the C-terminal region of factor D, contained the active serine residue. The amino acid sequence around this residue was determined.


2005 ◽  
Vol 49 (3) ◽  
pp. 973-980 ◽  
Author(s):  
Olivier Chesneau ◽  
Heidi Ligeret ◽  
Negin Hosan-Aghaie ◽  
Anne Morvan ◽  
Elie Dassa

ABSTRACT The Vga and Msr resistance determinants, encoded by mobile genetic elements in various staphylococcal strains, belong to a family of ATP-binding cassette (ABC) proteins whose functions and structures are ill defined. Their amino acid sequences are similar to those of proteins involved in the immunity of streptomycetes to the macrolide-lincosamide-streptogramin antibiotics that they produce. Sequence analysis of the genomes of the gram-positive bacteria with low G+C contents revealed that Lmo0919 from Listeria monocytogenes is more closely related to Vga variants than to Msr variants. In the present study we compared the antibiotic resistance profiles conferred by the Vga-like proteins in two staphylococcal hosts. It was shown that Vga(A), the Vga(A) variant [Vga(A)v], and Lmo0919 can confer resistance to lincosamides and streptogramin A compounds, while only Vga(B) is able to increase the level of resistance to pristinamycin, a mixture of streptogramin A and streptogramin B compounds. By using polyclonal antibodies, we found that the Vga(A) protein colocalized with the β subunit of the F1-F0 ATPase in the membrane fractions of staphylococcal cells. In order to identify functional units in these atypical ABC proteins, such as regions that might be involved in substrate specificity and/or membrane targeting, we analyzed the resistance phenotypes conferred by various plasmids carrying parts or modified versions of the vga(A) gene and we determined the subcellular localization of the gene products. Only polypeptides composed of two ABC domains were detected in the cell membranes. No region of drug specificity was identified. Resistance properties were dependent on the integrities of both Walker B motifs.


2006 ◽  
Vol 72 (5) ◽  
pp. 3321-3329 ◽  
Author(s):  
Kengo Inoue ◽  
Hiroshi Habe ◽  
Hisakazu Yamane ◽  
Hideaki Nojiri

ABSTRACT Nocardioides aromaticivorans IC177 is a gram-positive carbazole degrader. The genes encoding carbazole degradation (car genes) were cloned into a cosmid clone and sequenced partially to reveal 19 open reading frames. The car genes were clustered into the carAaCBaBbAcAd and carDFE gene clusters, encoding the enzymes responsible for the degradation of carbazole to anthranilate and 2-hydroxypenta-2,4-dienoate and of 2-hydroxypenta-2,4-dienoate to pyruvic acid and acetyl coenzyme A, respectively. The conserved amino acid motifs proposed to bind the Rieske-type [2Fe-2S] cluster and mononuclear iron, the Rieske-type [2Fe-2S] cluster, and flavin adenine dinucleotide were found in the deduced amino acid sequences of carAa, carAc, and carAd, respectively, which showed similarities with CarAa from Sphingomonas sp. strain KA1 (49% identity), CarAc from Pseudomonas resinovorans CA10 (31% identity), and AhdA4 from Sphingomonas sp. strain P2 (37% identity), respectively. Escherichia coli cells expressing CarAaAcAd exhibited major carbazole 1,9a-dioxygenase (CARDO) activity. These data showed that the IC177 CARDO is classified into class IIB, while gram-negative CARDOs are classified into class III or IIA, indicating that the respective CARDOs have diverse types of electron transfer components and high similarities of the terminal oxygenase. Reverse transcription-PCR (RT-PCR) experiments showed that the carAaCBaBbAcAd and carDFE gene clusters are operonic. The results of quantitative RT-PCR experiments indicated that transcription of both operons is induced by carbazole or its metabolite, whereas anthranilate is not an inducer. Biotransformation analysis showed that the IC177 CARDO exhibits significant activities for naphthalene, carbazole, and dibenzo-p-dioxin but less activity for dibenzofuran and biphenyl.


Plant Disease ◽  
2009 ◽  
Vol 93 (9) ◽  
pp. 970-970 ◽  
Author(s):  
R. M. Castro ◽  
E. Hernandez ◽  
F. Mora ◽  
P. Ramirez ◽  
R. W. Hammond

In early 2007, severe yellowing and chlorosis symptoms were observed in field-grown and greenhouse tomato (Solanum lycopersicum L.) plants in Costa Rica. Symptoms resembled those of the genus Crinivirus (family Closteroviridae), and large populations of whiteflies, including the greenhouse whitefly Trialeurodes vaporariorum (Westwood), were observed in the fields and on symptomatic plants. Total RNA was extracted from silica gel-dried tomato leaf tissue of 47 representative samples (all were from symptomatic plants) using TRI Reagent (Molecular Research Inc., Cincinnati, OH). Reverse transcription (RT)-PCR reactions were performed separately with each of the four primer sets with the Titan One-Tube RT-PCR Kit (Roche Diagnostics Corp., Chicago IL). Specific primers used for the detection of the criniviruses, Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV), were primer pair ToCV-p22-F (5′-ATGGATCTCACTGGTTGCTTGC-3′) and ToCV-p22-R (5′-TTATATATCACTCCCAAAGAAA-3′) specific for the p22 gene of ToCV RNA1 (1), primer pair ToCVCPmF (5′-TCTGGCAGTACCCGTTCGTGA-3′) and ToCVCPmR (5′-TACCGGCAGTCGTCCCATACC-3′) designed to be specific for the ToCV CPm gene of ToCV RNA2 (GenBank Accession No. AY903448) (2), primer pair ToCVHSP70F (5′-GGCGGTACTTTCGACACTTCTT-3′) and ToCVHSP70R (5′-ATTAACGCGCAAAACCATCTG-3′) designed to be specific for the Hsp70 gene of RNA2 of ToCV (GenBank Accession No. EU284744) (1), and primer pair TICV-CP-F and TICV-CP-R specific for the coat protein gene of TICV (1). Amplified DNA fragments (582 bp) were obtained from nine samples, four from the greenhouse and five from the open field, with the ToCV-p22 specific primers and were cloned into the pCRII TOPO cloning vector (Invitrogen, Carlsbad, CA). Nucleotide sequence analysis of all purified RT-PCR products verified their identity as ToCV, sharing 99.5 to 100% sequence identity among themselves and 96% to 98% sequence identity with previously reported ToCV p22 sequences from Florida (Accession No. AY903447), Spain (Accession No. DQ983480), and Greece (Accession No. EU284745). The presence of ToCV in the samples was confirmed by additional amplification and sequence analysis of the CPm (449-bp fragment) and Hsp70 (420-bp fragment) genes of ToCV RNA2 and sharing 98 to 99% sequence homology to Accession Nos. AY903448 and EU284774, respectively. One representative sequence of the p22 gene of the Costa Rican isolate was deposited at GenBank (Accession No. FJ809714). No PCR products were obtained using either the TICV-specific primers nor from healthy tomato tissue. The ToCV-positive samples were collected from a region in the Central Valley around Cartago, Costa Rica. To our knowledge, this is the first report of ToCV in Costa Rica. The economic impact on tomato has not yet been determined. Studies are underway to determine the incidence of ToCV in Costa Rica field-grown and greenhouse tomatoes. References: (1) A. R. A. Kataya et al. Plant Pathol. 57:819, 2008. (2) W. M. Wintermantel et al. Arch. Virol. 150:2287, 2005.


Plant Disease ◽  
2015 ◽  
Vol 99 (3) ◽  
pp. 423-423 ◽  
Author(s):  
J. A. M. Rezende ◽  
V. M. Camelo ◽  
D. Flôres ◽  
A. P. O. A. Mello ◽  
E. W. Kitajima ◽  
...  

Beet necrotic yellow vein virus (BNYVV) is an economically important pathogen of sugar beet (Beta vulgaris var. saccharifera) in several European, and Asian countries and in the United States (3). The virus is transmitted by the soil-inhabiting plasmodiophorid Polymyxa betae and causes the rhizomania disease of sugar beet. In November 2012, plants of B. vulgaris subsp. vulgaris cv. Boro (red table beet) exhibiting mainly severe characteristic root symptom of rhizomania were found in a commercial field located in the municipality of São José do Rio Pardo, State of São Paulo, Brazil. No characteristic virus-inducing foliar symptom was observed on diseased plants. The incidence of diseased plants was around 70% in the two visited crops. As the hairy root symptom is indicative of infection by BNYVV, the present study aimed to detect and identify this virus associated with the diseased plants. Preliminary leaf dip analysis by transmission electron microscopy revealed the presence of very few benyvirus-like particles. Total RNA was extracted from roots of three symptomatic plants and one asymptomatic plant according to Toth et al. (3). One-step reverse-transcription–polymerase chain reaction (RT-PCR) was performed as described by Morris et al. (2) with primers that amplify part of the coat protein gene at RNA2. The initial assumption that the hairy root symptom was associated with BNYVV infection was confirmed by the amplification of a fragment of ~500 bp from all three symptomatic samples. No amplicon was obtained from the asymptomatic control plant. Amplicons were directly sequenced, and the consensus nucleotide and deduced amino acid sequences showed 100% identity. The nucleotide sequence for one amplicon (Accession No. KM433683) was compared with other sequences deposited in GenBank. The nucleotide (468 nt) and deduced amino acid (156 aa) sequences shared 93 to 100 and 97 to 99% identity, respectively with the corresponding nucleotide and amino acid sequences for other isolates of type A of BNYVV. The virus was transmitted to three of 10 red table beet plants inoculated with contaminated soil, and infection was confirmed by nested RT-PCR, as described by Morris et al. (1), and nucleotide sequencing. This is the first report on the occurrence of BNYVV in Brazil, which certainly will affect the yield of red table beet in the producing region. Therefore, mapping of the occurrence of BNYVV in red table beet-producing areas in Brazil for containment of the spread of the virus is urgent. In the meantime, precautions should be taken to control the movement of contaminated soil and beet roots, carrots, or any vegetable grown on infested land that might introduce the virus to still virus-free regions. References: (1) J. Morris et al. J. Virol. Methods 95:163, 2001. (2) D. D. Sutic et al. Handbook of Plant Virus Diseases. CRC Press, Boca Raton, Florida, 1999. (3) I. K. Toth et al. Methods for the Detection and Quantification of Erwinia carotovora subsp. atroseptica (Pectobacterium carotovorum subsb. atrosepticum) on Potatoes: A Laboratory Manual. Scottish Crop Research Institute, Dundee, Scotland, 2002.


Plant Disease ◽  
2008 ◽  
Vol 92 (8) ◽  
pp. 1254-1254 ◽  
Author(s):  
T. Tian ◽  
H.-Y. Liu ◽  
S. T. Koike

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.


2021 ◽  
Author(s):  
Go-Eun Shin ◽  
Ji-Young Park ◽  
Kyoung-Ki Lee ◽  
Mi-Kyeong Ko ◽  
Bok-Kyung Ku ◽  
...  

Abstract Background Porcine reproductive and respiratory syndrome virus (PRRSV) has caused huge economic losses in the global swine industry. Frequent genetic variations in this virus cause difficulties in controlling and accurately diagnosing PRRSV. Methods In this study, we investigated the genetic characteristics of PRRSV-1 and PRRSV-2 circulating in Korea from January 2018 to September 2021 and evaluated three one-step real-time reverse transcription polymerase chain reaction (RT-PCR) assays. Results A total of 129 lung samples were collected, consisting of 47 samples for PRRSV-1, 62 samples for PRRSV-2, and 20 PRRSV-negative samples. Nucleotide sequence analysis of open reading frames (ORFs) 5, ORF6, and ORF7 genes from PRRSV samples showed that PRRSV-1 belonged to subgroup A (43/47, 91.49%) and subgroup C (4/47, 8.51%), whereas PRRSV-2 was classified as lineage 1 (25/62, 40.32%), Korean lineage (Kor) C (13/62, 20.97%), Kor B (10/62, 16.13%), lineage 5 (9/62, 14.52%), and Kor A (5/62, 8.06%). Amino acid sequence analysis showed that the neutralizing epitope and T cell epitope of PRRSV-1, and the decoy epitope region and hypervariable regions of PRRSV-2 had evolved under positive selection pressure. In particular, the key amino acid substitutions were found at positions 102 and 104 of glycoprotein 5 (GP5) in some PRRSV-2, and at positions 10 and 70 of membrane protein (M) in most PRRSV-2. In addition, one-step real-time RT-PCR assays, comprising two commercial tests and one test recommended by the World Organization for Animal Health (OIE), were evaluated. Conclusion The results revealed that two of the real-time RT-PCR assays had high sensitivities and specificities, whereas the real-time RT-PCR assay of the OIE had low sensitivity due to mismatches between nucleotides of Korean PRRSVs and forward primers. In this study, we genetically characterized recent PRRSV occurrences and evaluated three one-step real-time RT-PCR assays used in Korea.


Plant Disease ◽  
1997 ◽  
Vol 81 (9) ◽  
pp. 1095-1095 ◽  
Author(s):  
P. L. Ramos ◽  
O. Guerra ◽  
R. Peral ◽  
P. Oramas ◽  
R. G. Guevara ◽  
...  

Geminiviruses have become the most important virus group affecting tomatoes (Lycopersicon lycopersicum (L.) Karsten) in Cuba since they have been detected in all tomato-producing areas, causing serious losses. Recently, a whitefly-transmitted, monopartite geminivirus was detected in Cuba and identified as tomato yellow leaf curl virus-Israel (TYLCV-Is) (1). Samples collected from the main tomato-producing areas during the period 1995 to1996 were further analyzed by polymerase chain reaction (PCR) with degenerate primers (PAL1v1978 and PAR1c496) (2). Whereas in samples from most areas only TYLCV was detected, in some samples from the Havana area, two DNA fragments (approximately 1.4 and 1.1 kb) were amplified by PCR. The larger fragment was identified as part of the TYLCV-Is genome, confirming the previous report (1). The 1.1-kb fragment was cloned and its nucleotide sequence suggested that a new bipartite geminivirus was also present in those tomato samples. To clone the entire genome, tomato plants were inoculated by biolistics with DNA extract from field samples. After symptom expression, a viral DNA-enriched preparation from the inoculated tomatoes was independently digested with several restriction enzymes and the products were ligated into pZero plasmid (Invitrogen, San Diego, CA). Several clones in the 2.6-kb size range were characterized by restriction mapping and hybridization against component A and B heterologous probes. Two clones were selected as containing putative A and B components and their infectivity was tested by biolistic inoculation of tomato and pepper plants. The inoculated tomatoes developed a mild mottle in the younger leaves, whereas no symptoms were visible on the inoculated pepper plants. However, the presence of viral DNA was confirmed in both tomatoes and peppers by Southern blot hybridization analysis with A- and B-specific probes. Partial sequences of both components were obtained and their analysis showed that both components shared a 170-bases common region with a 95% identity. In addition, the nucleotide sequences of two open reading frames, one in each component (AC1 and BC1), were determined and compared with geminivirus sequences deposited in Gen-Bank. A dendogram generated with the CLUSTAL program and obtained with the AC1 and BC1 amino acid sequences, placed the new geminivirus in a cluster with tomato mottle virus (ToMoV; accession nos. L14460, L14461), Abutilon mosaic virus (AbMV; X15983, X15984), potato yellow mosaic virus (PYMV; D00940, D00941), and bean dwarf mosaic virus (BDMV; M88179, M88180). The percentages of identity obtained with the amino acid sequences were as follows. For AC1: ToMoV, 87%; PYMV, 79.5%; BDMV, 78.7%; and AbMV, 78%. For BC1 protein: BDMV, 92.8%; ToMoV, 89.1%; PYMV, 88.1%; and AbMV, 67.5%. In addition, the sequences were compared with partial nucleotide sequences (AC1, coat protein [CP], and common region) of a bipartite geminivirus affecting tomatoes in Jamaica (accession nos. U83855, U83854, and U83850). Interestingly, the common regions showed a higher percentage of identity (88%) than the CP and AC1 partial nucleotide sequences (86 and 74%, respectively). These data suggest that the virus reported here is a new geminivirus and the first bipartite geminivirus reported in Cuba. Thus, the name of Taino tomato mottle virus is proposed. (Taino refers to the name of the inhabitants of Cuba at the time of Columbus's arrival in the Caribbean). References: (1) P. L. Ramos et al. Plant Dis. 80:1208, 1996. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993.


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