scholarly journals First Report on the Occurrence of Grapevine leafroll-associated virus 7 and 9 in Chilean Grapevines

Plant Disease ◽  
2008 ◽  
Vol 92 (8) ◽  
pp. 1252-1252 ◽  
Author(s):  
E. A. Engel ◽  
P. Escobar ◽  
C. Montt ◽  
S. Gómez-Talquenca ◽  
P. D. T. Valenzuela

Grapevine is one of the oldest horticultural crops and represents a highly valuable agricultural commodity. So far, nine distinct Grapevine leafroll-associated viruses (GLRaVs) within the Closteroviridae family have been found to be associated with grapevine leafroll disease (3). Previous studies have demonstrated a high incidence of GLRaV-1, -2, and -3 in Chile (2). To determine if other GLRaVs were present, 21 dormant cane samples were screened with a comprehensive 70-mer oligonucleotide microarray designed to simultaneously detect all grapevine viruses with total or partial genomic sequence available. The array contained 570 unique probes designed against specific regions of more than 40 viral genomes (E. Engel et al., 15th ICVG [Abstr.], 2006). One sample (cv. Black Seedless) showing a microarray hybridization pattern compatible with a mixed infection of GLRaV-7 and GLRaV-1 was analyzed by ELISA using GLRaV-7 specific antibodies (Agritest, Valenzano, Italy) and reverse transcription (RT)-PCR using virus-specific primers LR7-F: 5′- TAT ATC CCA ACG GAG ATG GC -3′ and LR7-R: 5′- ATG TTC CTC CAC CAA AAT CG -3′ (based on GenBank Accession No. Y15987). The serological analysis confirmed the presence of GLRaV-7 with further confirmation by the RT-PCR product of 502 bp corresponding to a fragment of the HSP70h gene that was cloned and sequenced. The Chilean GLRaV-7 sequence (GenBank Accession No. EU334662) showed 94% nucleotide and 95% amino acid identity when compared with a corresponding region of another GLRaV-7 isolate from Albania (GenBank Accession No. Y15987). GLRaV-1 infection was confirmed by ELISA (Bioreba AG, Reinach, Switzerland) and RT-PCR. A second sample (cv. Tintorera) showing microarray hybridization pattern compatible with a mixed infection of GLRaV-9 and Grapevine virus A (GVA) was analyzed by RT-PCR using virus-specific primers LR9-F: 5′- CGG CAT AAG AAA AGA TGG CAC -3′ and LR9-R: 5′- TCA TTC ACC ACT GCT TGA AC -3′ (1). The RT-PCR product of 393 bp corresponding to a fragment of the HSP70h gene was cloned and sequenced (GenBank Accession No. EU334663), showing 94% nucleotide and 95% amino acid identity when compared with a corresponding region of another GLRaV-9 isolate from the United States (GenBank Accession No. AY297819). Since there are no commercial antibodies available for GLRaV-9 detection, a second pair of primers, LR9-F1: 5′- AAA GGT TTC TGC TGG TTA CC -3′ and LR9-R1: 5′- CTT TCA GAA CAG TCC TCC TC -3′ that amplified a fragment of ORF1a was also used. The 301-bp product was cloned and sequenced (GenBank Accession No. EU588989) showing 93.7% nucleotide and 98% amino acid identity when compared with a corresponding region of another GLRaV-9 isolate (GenBank Accession No. AY297819). GVA infection was confirmed by ELISA (Bioreba AG) and RT-PCR. To our knowledge, this is the first report of GLRaV-7 and GLRaV-9 in Chile. Further studies will help determine the effect and incidence of these viruses in Chilean grapevines. References: (1) R. Alkowni et al. J. Plant Pathol. 86:123, 2004. (2) N. Fiore et al. J. Plant Pathol. 90:125, 2008. (3) G. P. Martelli and E. Boudon-Padieu. Options Méditerr. B55, 2006.

Plant Disease ◽  
2011 ◽  
Vol 95 (3) ◽  
pp. 362-362 ◽  
Author(s):  
C.-H. Huang ◽  
F.-J. Jan

In March of 2010, calendula (Calendula officinalis L.), a perennial herb known as the pot marigold, showing chlorotic spots on leaves, chlorosis, and stunting were collected from Puli Township, Nantou County, Taiwan. The disorder occurred in more than 50% of the calendula plants in the field. A virus culture isolated from one of the symptomatic calendulas was established in Chenopodium quinoa through triple single-lesion isolation and designated as TwCa1. With transmission electron microscopy (TEM), negatively stained flexuous filamentous virions approximately 12 × 720 nm were observed in the crude sap of TwCa1-infected C. quinoa leaves and pinwheel inclusion bodies were found in the infected cells. On the basis of the sizes of the viral particles and inclusion bodies, isolate TwCa1 was a suspected potyvirus. By reverse transcription (RT)-PCR and potyvirus degenerate primers (Hrp5/Pot1) (1,2), a 0.65-kb DNA fragment, which included the 3′-end of the NIb gene and the 5′-end of coat protein (CP) gene of the virus, was amplified from total RNA isolated from TwCa1-infected plants. The amplified DNA fragment was cloned and sequenced. A homology search indicated that the new calendula-infecting virus in Taiwan might belong to Bidens mottle virus (BiMoV) because its partial genomic sequence shared 94.9 to 97.3% nucleotide and 96.6 to 98.1% amino acid identity with 11 BiMoV isolates available in NCBI GenBank. Primer pairs Hrp5/oligo d(T) were used to amplify the 3′-end genome of BioMV TwCa1 including the 3′-end of the NIb gene, the full-length CP gene, and the 3′-nontranslatable region of the virus. The 807-nt CP gene of TwCa1 (Accession No. HQ117871) shared 97.3 to 98.6% nucleotide and 98.5 to 98.9% amino acid identity with those of 11 BiMoV isolates available in GenBank. Results from TEM observations and CP gene sequence analysis indicated that TwCa1 is an isolate of BiMoV. BiMoV was later detected by RT-PCR in eight symptomatic calendulas collected from the same field. To our knowledge, this is the first report of BiMoV infecting calendula in Taiwan. This newly identified calendula-infecting BiMoV could have a direct impact on the economically important vegetable and floral industry in Taiwan. References: (1) C. C. Chen et al. Bot. Stud. 947:369, 2006. (2) D. Colinet and J. Kummert. J. Virol. Methods 45:149, 1993.


Plant Disease ◽  
2009 ◽  
Vol 93 (2) ◽  
pp. 196-196 ◽  
Author(s):  
B. N. Shen ◽  
Y. X. Zheng ◽  
W. H. Chen ◽  
T. Y. Chang ◽  
H.-M. Ku ◽  
...  

Pineapple (Ananas comosus) is one of the major fruit crops in Taiwan, accounting for 275 million U.S. dollars in 2006, following betel nut and citrus production in crop value. Tainung No. 17 is the most important cultivar, accounting for more than 70% of pineapples planted. Mealybug wilt of pineapple (MWP) is one of the most destructive diseases of pineapple. Pineapple mealybug wilt-associated virus-1 (PMWaV-1), PMWaV-2, and PMWaV-3 were identified as three distinct species in Ampelovirus from diseased Hawaiian pineapple (1,2). In November of 2007, pineapples (cv. Tainung No. 17) planted in Pingtung County of southern Taiwan showed symptoms similar to MWP. Mealybugs (Dysmicoccus brevipes) were also found. Three primer pairs, 225/226, 223/224, and 263/264 described previously specific for the HSP70h genes of PMWaV-1 (1), -2, and -3 (2), respectively, were used to detect the presence of these three viruses by reverse transcription (RT)-PCR. Expected DNA fragments of 590, 610, and 499 nt were obtained from the total RNA isolated from the leaves of diseased pineapples with primer pairs 225/226, 223/224, and 263/264, respectively. The RT-PCR amplified fragments were cloned, sequenced, and analyzed. The 590-nt fragment (Accession No. EU769113) shared 91.6 to 99.5% nucleotide and 96.8 to 99.5% amino acid identity to those of five isolates of PMWaV-1 available in the GenBank; one each from Hawaii (Accession No. AF414119) and Thailand (Accession No. EF620774) and three from Australia (Accession Nos. EF488752, EF467923, and EF467925). The 610-nt fragment (Accession No. EU769115) showed 98.7 and 99.7% nucleotide and 98% and 100% amino acid identity to those of PMWaV-2 from Hawaii (Accession No. AF283103) and Thailand (Accession No. EU016675), respectively. The 499-nt fragment (Accession No. FJ209047) shared 86.8 to 99.0% nucleotide and 94.0 to 100.0% amino acid identity to those of five PMWaV-3 isolates available in the GenBank; one from Hawaii (Accession No. DQ399259) and four from Australia (Accession Nos. EF467918, EF467919, EF488754, and EF488755). Using primer pairs FJ08-1 (5′-ATGGCTGATTCGAGC)/FJ08-2 (5′-TTATTTGCGTCCACC), FJ08-7 (5′-AGTGAGATTGATCGT)/FJ08-8 (5′-TGCAGGTATCCGCTG), and FJ08-35 (5′-AACGACCGAACTCGC)/FJ08-36 (5′-ATACTACAGATATTG) specific to the coat protein (CP) genes of PMWaV-1, -2, and -3, respectively, expected DNA fragments of 774, 909, and 789 nt were amplified by RT-PCR. The 774-nt CP gene of PMWaV-1 (Accession No. EU769114) shared 99% nucleotide and 98.4% amino acid identity to those of Hawaiian isolate (Accession No. AF414119). The 909-nt CP gene of PMWaV-2 (Accession No. EU769116) shared 99.0 and 99.1% nucleotide identity with isolates from Hawaii (Accession No. AF283103) and Cuba (Accession No. DQ225114), respectively, and 99.3% amino acid identity with both. The 789-nt CP gene of PMWaV-3 (Accession No. FJ209048) shared 99.1% nucleotide and 98.1% amino acid identity to those of the Hawaiian isolate (Accession No. DQ399259). One to two viruses among PMWaV-1, -2, and -3 were detected in all 40 samples collected from diseased pineapples. To our knowledge, this is the first report to identify three PMWaVs in the most important and widely planted pineapple cultivar in Taiwan, Tainung No. 17, by molecular characterization of the HSP70h and CP genes. References: (1) D. M. Sether et al. Plant Dis. 85:856, 2001. (2) D. M. Sether et al. Plant Dis. 89:450, 2005.


1995 ◽  
Vol 308 (1) ◽  
pp. 97-104 ◽  
Author(s):  
H G Morrison ◽  
M F Oleksiak ◽  
N W Cornell ◽  
M L Sogin ◽  
J J Stegeman

Cytochrome P-450-mediated responses to environmental challenges are well known in diverse animal taxa, but the evolution of the complex gene superfamily coding for these enzymes is poorly understood. Here we report a phylogenetic analysis of the cytochrome P-450 1A (CYP1A) genes including two new sequences determined from teleost fish, toadfish (Opsanus tau) and scup (Stenotomus chrysops). Degenerate PCR primers were used to amplify a 1.2 kbp fragment from liver cDNA. The toadfish PCR product was used as a probe to identify a full-length CYP1A clone from a toadfish liver cDNA library. The entire coding region of the scup CYP1A was obtained by rapid amplification of cDNA ends (RACE) using specific primers based on the sequence of the partial PCR product. The predicted protein sequences for toadfish and scup CYP1A shared 78% and 83% amino acid identity with rainbow trout CYP1A1 respectively. Amino acid identity with mammalian CYP1A proteins ranged from 51 to 60% for 505 aligned positions. Phylogenetic analysis of four teleost fish CYP1A genes (trout, toadfish, scup and plaice) and 12 mammalian CYP1A genes suggests a monophyletic origin of the teleost genes, with the trout gene being most divergent, and indicates three distinct groupings: mammalian 1A1, mammalian 1A2, and fish 1A. This supports the idea that the gene duplication event which gave rise to CYP1A1 and CYP1A2 occurred after the divergence of the lines leading to mammals and fish. These results establish a molecular phylogeny within the CYP1A subfamily, the first such detailed phylogenetic analysis within a cytochrome P-450 family.


Plant Disease ◽  
2009 ◽  
Vol 93 (1) ◽  
pp. 107-107 ◽  
Author(s):  
Y. H. Cheng ◽  
R. Y. Wang ◽  
C. C. Chen ◽  
C. A. Chang ◽  
F.-J. Jan

In May of 2006, samples from tomato plants (Solanum lycopersicum cv. Known-you 301) exhibiting necrotic symptoms on stems, petioles, and leaves were collected from Chiayi County, Taiwan. Double-antibody sandwich-ELISAs were performed using Cucumber mosaic virus, Tomato mosaic virus, Potato virus Y, Watermelon silver mottle virus, and Chilli veinal mottle virus (ChiVMV) polyclonal antibodies. Three of eight samples reacted with antibodies against ChiVMV but not with the others. Using the potyvirus degenerate primers (Hrp 5/Pot 1) (2), an expected 1.5-kb DNA fragment including the 3′-end of the NIb gene, the complete coat protein (CP) gene, and the 3′-nontranslatable region of the virus was amplified from total RNA isolated from these three samples by reverse transcription (RT)-PCR. A homology search in GenBank indicated that the new tomato-infecting virus in Taiwan belongs to Pepper veinal mottle virus (PVMV) since they shared >90% amino acid identity in the CP gene. A virus culture (Tom1) isolated from one of the diseased tomatoes was then established in Chenopodium quinoa and Nicotiana benthamiana and the CP gene was amplified and sequenced (GenBank Accession No. EU719647). Comparisons of the 807-nt CP gene with those of five PVMV isolates available in GenBank showed 81.5 to 93.1% nucleotide and 90.0 to 97.8% amino acid identity. Tom1 induced irregular necrotic lesions on stems, petioles, and leaves of tomato while inducing only mild mottle symptoms on pepper. Serological cross reaction between ChiVMV and PVMV has been observed previously (1,3) and also found in this study. To differentiate these two potyviruses by RT-PCR, primer pair CPVMVup/dw (5′-TATTC(T/C)TCAGTGTGG(A/T/C)T(T/C)CCACCAT and 5′-(T/C)C(A/T)C(A/T)(A/T/G)(A/T)AA(A/G)CCATAA(A/C)(A/C)ATA(A/G)T(T/C)T) was designed on the basis of the comparison of the CP gene and the 3′-nontranslatable region of the PVMV and ChiVMV. DNA fragments of 171 and 259 bp are expected to be amplified from ChiVMV and PVMV, respectively, by RT-PCR with primers CPVMVup/dw. In a field survey done in 2006, samples from diseased peppers (Capsicum annuum) that reacted with the polyclonal antibodies against ChiVMV were further identified by RT-PCR with primers CPVMVup/dw, indicating that both ChiVMV and PVMV infected pepper crops (Capsicum spp.) in Taiwan. A pepper isolate (Pep1) of PVMV was obtained from Nantou County through three times of single lesion passages on C. quinoa and then propagated on N. benthamiana. The CP gene of Pep1 was amplified and sequenced (GenBank Accession No. EU719646) and found to share 99.1% nucleotide and 100% amino acid identity with that of Tom1. Pep1 caused mild mottle symptoms on leaves of both tomato and pepper. To our knowledge, this is the first report of the presence of PVMV in Taiwan as well as in East Asia. References: (1) B. Moury et al. Phytopathology 95:227, 2005. (2) S. S. Pappu et al. Plant Dis. 82:1121, 1998. (3) W. S. Tsai et al. Plant Pathol. 58:408, 2008.


Plant Disease ◽  
2010 ◽  
Vol 94 (12) ◽  
pp. 1507-1507 ◽  
Author(s):  
C. V. Padilla ◽  
E. Cretazzo ◽  
I. Hita ◽  
N. López ◽  
V. Padilla ◽  
...  

Grapevine leafroll-associated viruses (GLRaVs) cause significant reductions in yield and quality in the wine industry worldwide. At least nine different GLRaVs have been found in different regions of the world. In the process of virus indexing of candidate grapevine clones for certification, which includes grafting of scions onto rootstocks, we observed strong leafroll symptoms 1 year after grafting with one vine of cv. Estaladina in Castilla y León, Spain and one vine of cv. Tempranillo in La Rioja, Spain, collected in 2008 and 2007, respectively. Both vines tested positive by real-time reverse transcription (RT)-PCR with TaqMan probes specific for Grapevine leafroll-associated virus 5 and double-antibody sandwich (DAS)-ELISA with a mix of monoclonal antibodies that recognizes GLRaV-4, 5, 6, 7, and 9 (Bioreba, Reinach, Switzerland). RNA extracts of both GLRaV-5 positive vines were analyzed by conventional RT-PCR with a pair of consensus degenerated primers derived from GLRaV-5 hsp70 sequences available in GenBank: LR5HYF (5′-TGGGATGAAYAARTTCAATGC-3′) and LR5HYR (5′-TGAAATTCCTCATRTARGAGC-3′) that amplified a 250-bp fragment. Amplicons were cloned and the comparison of the amino acid sequences (Estaladina isolate, Est110: Accession No. HM208622; Tempranillo isolate, Tem020: Accession No. HM208618) showed in the case of the Est110 isolate, 100 and 82.6% identity, respectively, with the homologous genes of one GLRaV-5 isolate from the United States (AF233934 [3]) and Argentina (EU815935 [2]). For isolate Tem020, the hsp70 gene showed 97.1 and 81.2% amino acid identity with the homologous hsp70 genes of the United States and Argentina isolates. The coat protein (cp) genes of both isolates were also amplified and cloned using the specific GLRaV-5 primers, LR53413 (5′-CGTGATACAAGGTAGGACAACCGT-3′) and LR53843 (5′-CTTGCACTATCGCTGCCGTGAAT-3′), designed according to the sequence of AF233934. Fragments were of the expected size (430 bp) and the nucleotide sequences were obtained (Est110: Accession No. HM363522; Tem020: Accession No. HM363523) and used for pairwise nucleotide comparisons. The Est110 isolate showed 96.7 and 97.5% amino acid identity with the isolates from the United States and Argentina, respectively, while the Tem020 isolate showed 94.8 and 95.6% identity, respectively. Amino acid identity of Est110 and Tem020 cp genes was 100% when compared with the homologous genes of isolates AF233934 and EU815935. To our knowledge this is the first report of GRLaV-5 in Spain. Since 2008, we have detected eight additional vines positive for this virus in 200 clones analyzed for certification, suggesting that the incidence of GLRaV-5 in Spain could be widespread. This research indicates that virus indexing for GLRaV should be included in certification schemes for grapevine candidate clones (1) in Spain. References: (1) Anonymous. OEPP/EPPO Bull. 38:422, 2008. (2) S. Gomez Talquenca et al. Virus Genes 38:184, 2009. (3) F. Osman et al. J. Virol. Methods 141:22, 2007.


2004 ◽  
Vol 1 (3) ◽  
pp. 173-179
Author(s):  
Gao Zhi-Qiang ◽  
Guo Xin ◽  
Cha Zhen-Lin ◽  
Chen Yan-Hong ◽  
Yang Han-Chun

AbstractThree Porcine reproductive and respiratory syndrome virus (PRRSV) isolates (HB-1(sh)/2002, HB-2(sh)/2002 and JX-1/2002) were obtained from pig farms in Hebei and Jiangxi provinces, China. The complete ORF5 gene of the isolates was amplified using RT-PCR and sequenced. It was shown that ORF5 genes of all isolates encoded 200 amino acids. Comparing ORF5 genes of the three isolates and published sequences for five other PRRSV isolates in China, variation analysis showed that all of the isolates were of the American genotype, with 88.2–99.0% amino acid identity. ORF5 genes among BJ-4, S1 and J1 had higher similarity, sharing 98–99% identity of the deduced amino acids. HB-1(sh)/2002, HB-2(sh)/2002 and JX-1/2002 and CH-1a presented 92–96% identity among their ORF5 genes. Phylogenetic analysis revealed that these isolates could be divided into two subgroups based on the genetic distance of their ORF5 gene: the first subgroup comprised BJ-4, S1 and J1 and was closer to VR2332 and vaccine strains; the second included HB-1(sh)/2002, HB-2(sh)/2002, JX-1/2002 and CH-1a.


Plant Disease ◽  
2013 ◽  
Vol 97 (10) ◽  
pp. 1389-1389 ◽  
Author(s):  
M. A. Guaragna ◽  
J. Lamborn ◽  
D. Groth-Helms ◽  
S. Juszczak ◽  
D. Mollov ◽  
...  

Ornamental flower bulbs (including true bulbs, bulbils, corms, tubers, and rhizomes) are increasingly important floriculture crops. Amaryllis is a small genus of flowering bulbs, with two species. The South African native, Amaryllis belladonna, also known as belladonna lily, Jersey lily, naked lady, Amarillo, or March lily, is one of numerous ornamental species with the common name “lily” due to their flower shape and growth habit. Amaryllis are popular for their 6- to 10-inch trumpet shaped colorful flowers that are borne on 1- to 2-foot stalks. In January, 2011, a home gardener in California observed mosaic symptoms on the leaves of A. belladonna growing in her garden. Leaf samples were sent to Agdia Inc. for testing. Samples tested positive for the presence of Potyvirus in a reverse transcription (RT)-PCR screen using universal potyvirus primers (2) yielding the expected ∼1,600-bp product corresponding to the partial nuclear inclusion body (NIb) gene, full-length coat protein (CP) gene, and 3′ end untranslated region (UTR). Electron microscopy of symptomatic leaves confirmed the presence of filamentous potyvirus-like particles. The RT-PCR amplicon was cloned and sequenced (2); the 1,616-bp consensus sequence was deposited in GenBank (Accession No. JX865782). NCBI BLAST analysis of the consensus sequence revealed highest identities with isolates of Nerine yellow stripe virus (NeYSV; family Potyviridae, genus Potyvirus). Pair-wise analyses of the 261 amino acid sequence of the predicted CP had 88% sequence identity with a Stenomesson isolate reported from the Netherlands (EU042758); 87% identity with Hymenocallis and Nerine isolates, both also from the Netherlands (EF362622 and EF362621, respectively); and, 86% with two New Zealand isolates infecting Amaryllis or Vallota (FJ618537 and DQ407932, respectively). The five Netherlands and New Zealand isolates are more closely related to each other than to the U.S. isolate as they share 93 to 98% CP identity. When using viral genome sequence relatedness as a criterion for defining potyvirus species, isolates with CP amino acid identity greater than 80% are considered the same species (1). The predicted coat protein gene of the California isolate was sub-cloned into the bacterial expression vector pET44 EK/LIC. Serological analysis of coat protein expressing clones in ELISA and Western Blot analysis using a potyvirus broad-spectrum reacting monoclonal antibody PTY-2 (3) and a NeYSV-specific rabbit antiserum (Applied Plant Research, Lisse, The Netherlands) resulted in positive reactions. NeYSV has previously been reported in the United Kingdom, the Netherlands, Australia, and New Zealand. Based on the results of electron microscopy, RT-PCR, nucleotide and amino acid identity, and serological reactivity, we identify this virus as a U.S. isolate of NeYSV, NeYSV-US. To our knowledge, this is the first report of Nerine yellow stripe virus in the United States. Development of antisera specific to this U.S. isolate is in progress. References: (1) A. Gibbs and K. Ohshima. Ann. Rev. Phytopathol. 48:205, 2010. (2) R. L. Jordan et al. Acta Hortic. 901:159, 2011. (3) R. L. Jordan and J. Hammond. J. Gen. Virol. 72:1531, 1991.


Plant Disease ◽  
2010 ◽  
Vol 94 (7) ◽  
pp. 920-920 ◽  
Author(s):  
Y.-X. Zheng ◽  
C.-H. Huang ◽  
Y.-H. Cheng ◽  
F.-Y. Kuo ◽  
F.-J. Jan

A new disorder on pepper showing symptoms of chlorosis and chlorotic spots on leaves was observed in sweet pepper (Capsicum annuum cv. Andalus) fields in Ren-Ai Township, Nantou County in July, 2009. The disorder occurred in more than 30% of the pepper plants, with a height of approximately 40 cm (1.5 feet), which was approximately one-half the size of the asymptomatic ones. Symptomatic plants bore much smaller fruits with abnormal shapes. Three symptomatic sweet pepper plants were collected and tested for potential viruses. Reverse transcription (RT)-PCR was performed for the detection using three degenerate primer pairs, gL3637/gL4435c for tospoviruses (2), Hrp5/Pot1 for potyviruses (1,3), and Tob-Uni1/Tob-Uni2 for tobamoviruses (4), and specific primers, FJJ2001-7/FJJ2001-8 (5′-TATGTCCATGGACAAATCCGAATCA and 5′-TCTCTGGATCCACGAGTTCAAACTGGGAG) for the coat protein gene of Cucumber mosaic virus (CMV). An 819-nt DNA fragment containing the partial L RNA of tospovirus was amplified from the total RNA isolated from each of these three samples by RT-PCR with primer pair gL3637/gL4435c. One amplified fragment was cloned and sequenced. A homology search in GenBank indicated that the new pepper-infecting virus in Taiwan was Tomato spotted wilt virus (TSWV) since the partial L RNA shared more than 94.5% nucleotide and 98.2% amino acid identity with five TSWV isolates (Accession Nos. AB190813, AB198742, AY070218, D10066, and NC_002052). No DNA fragment was obtained by RT-PCR using primer pairs for CMV, potyviruses, or tobamoviruses. A virus culture (TwPep1) isolated from one of the symptomatic sweet pepper plants was then established in Nicotiana tabacum cv. White Burley and N. benthamiana through triple single-lesion isolation. TWPep1 reacted positively only to the antiserum against TSWV by indirect-ELISA but not to those of Watermelon silver mottle virus, Capsicum chlorosis virus, Tobacco mosaic virus, Tomato mosaic virus, and CMV. Partial L RNA and the full-length nucleocapsid (N) gene of TWPep1 were obtained by RT-PCR with primer pairs gL3637/gL4435c and FJJ2002-74/FJJ2002-75 (5′-GCGCGCGGATCCTAATTTAACTTACARCTGCT 5′-TGCTGCCTCGAGCATACGGTCAAAGCATATAA), respectively. The 819-nt L RNA conserved region of TwPep1 (Accession No. GU222652) shared 94.4 to 97.7% nucleotide and 98.2 to 100% amino acid identity with those available in GenBank. The 777-bp N gene of TwPep1 (Accession No. GU222651) shared 96.7 to 99.1% nucleotide and 97.3 to 99.6% amino acid identity with 37 TSWV isolates available in GenBank. Sequence comparisons indicated that TwPep1 is an isolate of TSWV. TSWV was later detected by RT-PCR in all 10 symptomatic samples of sweet pepper plants collected from five fields in August 2009. To our knowledge, this is the first report of TSWV in sweet pepper in Taiwan. This is also the first demonstration of isolation and characterization of TSWV in Taiwan although TSWV was once detected in lisianthus (Eustoma rusellianum) by RT-PCR (1) but the isolation was not successful then. The occurrence of TSWV in pepper will have a direct economic impact on the important vegetable and floral industry in Taiwan because TSWV reportedly comprises a wide host range. References: (1) C. C. Chen et al. Bot. Stud. 947:369, 2006. (2) F. H. Chu et al. Phytopathology 91:361, 2001. (3) D. Colinet and J. Kummert. J. Virol. Methods 45:149, 1993. (4) B. Letschert et al. J. Virol. Methods 106:1, 2002.


2012 ◽  
Author(s):  
◽  
Judith Diane Gohndrone

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Cardioviruses are members of the Picornaviridae family capable of causing several forms of disease including myocarditis, encephalitis, diabetes, fetal death, and neuron degeneration. A wide range of hosts are susceptible to cardioviruses with rodents frequently being suspected as the viral reservoir following outbreaks of infection. In this study we discovered a novel Cardiovirus, provisionally designated Boone Cardiovirus (BCV). BCV was identified in the feces of laboratory rats using a pan picornavirus-PCR assay. Phylogenetic analysis revealed that BCV is a new species within the Cardiovirus genus distinct from both Encephalomyelitis Virus (EMCV) and Theilovirus. With these two species, BCV shares [less-than]45% amino acid identity in the polyprotein region and [less-than]50% amino acid identity in the capsid proteins. To assess the prevalence of BCV in laboratory rodents a sensitive hemi-nested RT-PCR assay was developed to screen fecal samples. Screening revealed that 20% of rat samples and 30% of research institutions tested positive for BCV. During the screening process a second isolate of BCV was also identified. Phylogenetic analysis of the second isolate determined it shared 91% amino acid identity with the original strain in the polyprotein region. Identification of additional BCV strains aids in the understanding of BCV variability and provides additional information for the development of comprehensive PCR and serologic screening assays. As no definitive clinical disease has been observed with BCV, a quantitative RT-PCR (qRT-PCR) assay was developed to screen rat tissues for sites of replication. BCV was found predominately localized to the gastrointestinal tract with the highest titers in the duodenum. Screening animals of various ages also revealed that BCV causes persistent infections in laboratory rats. In addition, to the RT-PCR and qRT-PCR assays the VP2 protein was expressed and purified for use in Western blot analysis of rat serum for preliminary serologic data on BCV. Collectively, the RT-PCR and Western blot assays provide a foundation for BCV detection and will enable researchers to screen animals prior to experiments. These assays will also make it possible to establish BCV-free rat colonies as virally infected research animals can confound and invalidate research findings. Preliminary data from infections of nude rats suggest that BCV is capable of replication and the immune system of immunocompetent animals plays a role in modulating infections as once T-cell are eliminated viral titers are approximately 4 logs higher. Furthermore, the discovery of BCV may lead to the establishment of research models that can provide valuable information including host-viral interactions during persistent infections.


Plant Disease ◽  
2008 ◽  
Vol 92 (8) ◽  
pp. 1253-1253 ◽  
Author(s):  
T. Wei ◽  
M. N. Pearson ◽  
D. Cohen ◽  
J. Z. Tang ◽  
G. R. G. Clover

In February 2004, leaf yellowing, mottling, and mosaics were observed on a few plants of a Zantedeschia sp. (calla lily) growing in Rangiora, Canterbury, New Zealand. Zantedeschia spp. are known to be susceptible to at least 13 virus species (1). No symptoms were observed on Chenopodium amaranticolor, C. quinoa, Cucumis sativus, Gomphrena globosa, Nicotiana benthamiana, N. clevelandii, N. occidentalis, or N. tabacum when inoculated with sap from symptomatic plants. However, electron microscopy of crude sap preparations from a symptomatic Zantedeschia sp. and inoculated N. clevelandii plants revealed the presence of flexuous, filamentous virus particles approximately 700 nm long and 12 nm wide. No virus particles were seen in the other inoculated indicator species. Nucleic acid was extracted from leaves of the infected Zantedeschia sp. and N. clevelandii plants and tested in reverse transcription (RT)-PCR using published potyvirus-specific primers (4). PCR amplicons of the expected size (327 bp) were obtained from both plant species and sequenced directly. The products were identical, and a BLAST search in GenBank showed 99% nucleotide identity with a Taiwanese isolate of the species Zantedeschia mosaic virus (ZaMV) (GenBank Accession No. AY026463). A product of 1,531 bp (GenBank Accession No. EU544542) was amplified from symptomatic Zantedeschia by RT-PCR using novel forward (5′-GCACGGCAGATAAACACGAC-3′) and reverse (5′-GTGGGCAACCTTCAACTGTG-3′) primers designed to amplify the 3′ untranslated region (3′UTR), coat protein (CP), and partial nuclear inclusion b protein (NIb) genes. The product was sequenced and had 94% nucleotide identity with a South Korean ZaMV isolate (GenBank Accession No. AB081519), with 95% nucleotide (97% amino acid) identity in the CP gene. A second crop of Zantedeschia spp. in Tauranga, New Zealand (approximately 700 km north of Rangiora) was observed to have similar disease symptoms. Symptomatic plants tested positive in ELISA using a potyvirus-specific monoclonal antibody (Agdia Inc., Elkhart, IN). Nucleic acid was extracted from leaves of symptomatic plants and tested in RT-PCR using potyvirus-specific primer pairs, PV2I/T7 and D335 and U335 and PV1/SP6, which amplify overlapping regions within the 3′UTR, CP, and NIb genes (2,3). The products were sequenced and a consensus sequence of 1,793 bp was generated (GenBank Accession No. EU532065). A BLAST search showed that the sequence had 78% nucleotide (88% amino acid) identity with Zantedeschia mild mosaic virus (ZaMMV) (GenBank Accession No. AY626825). However, the sequences had only 73% nucleotide (79% amino acid) identity in the CP gene, and therefore, this second virus may be a distinct species. To our knowledge, this is the first report of ZaMV in New Zealand. Cut flowers are an increasingly important commodity in New Zealand and Zantedeschia is one of the most important crops; in 2005, exports of rhizomes and cut flowers of the genus were worth NZ$10.9 million. These viral diseases may require management to ensure that the quality of production is maintained. References: (1) C. H. Huang et al. Plant Pathol. 56:183, 2007. (2) S. A. Langeveld et al. J. Gen. Virol. 72:1531, 1991. (3) A. M. Mackenzie et al. Arch. Virol. 143:903, 1998. (4) V. Marie-Jeanne et al. J. Phytopathol. 148:141, 2000.


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