A Begomovirus Associated with Leaf Curling and Chlorosis of Soybean in Sinaloa, Mexico is Related to Pepper golden mosaic virus

Since June 2001, symptoms of yellowing, leaf curling, crumpling, and stunted growth were observed on soybean (Glycine max Merr.) plants in Sinaloa, Mexico. These symptoms and the presence of whiteflies (Bemisia tabaci Gennadius) in the affected fields suggested a viral etiology. Samples from symptomatic plants were collected from commercial fields and analyzed for the presence of begomoviruses using DNA hybridization, and as a probe, the DNA A of Pepper huasteco virus at low stringency (2). Thirty-five positive samples were subsequently used for polymerase chain reaction (PCR) amplification with the degenerate primers RepMot and CPMot (1). These primers direct the amplification of a DNA A segment comprising the entire intergenic region (IR) and the first 210 bp of the coat protein (CP) gene, which is highly variable in size and nucleotide sequence among begomoviruses. PCR products were obtained for 25 of 35 samples and five of these were cloned into the pGEM-T easy vector (Promega, Madison, WI) and sequenced. The 571-bp DNA sequence (GenBank Accession No. AY905553) was compared with sequences of other begomoviruses in GenBank using the Clustal alignment method (MegAlign, DNASTAR software, London). The sequence was 74 and 70% identical to the Pepper golden mosaic virus (PepGMV; GenBank Accession No. U57457) and Cabbage leaf curl virus (CaLCuV; GenBank Accession No. U65529) sequences, respectively. Interestingly, the partial coat protein gene sequence (210 nt) of this soybean-infecting virus was 98% identical to the CP gene of Tobacco apical stunt virus (TbASV; GenBank Accession No. AF076855). Nonetheless, the known sequence of TbASV intergenic region (GenBank Accession No. AF077744) is very different from the homologous region of the soybean virus (34% of nucleotide identity). Analysis of the soybean virus intergenic region revealed that it harbors almost identical iterons (i.e., Rep-binding sites) to PepGMV, suggesting a close relationship between these two viruses. Soybean-infecting geminiviruses have been previously reported only from Asia; however, the partial sequence of a begomovirus isolated from soybean in Brazil was recently deposited in Genbank (Accession No. AY436328). Sequence comparisons between the Brazilian and Mexican isolates showed these viruses are less related with a nucleotide identity of 46%. Taken together, our data indicate that the virus identified in this study might be either a different strain of PepGMV adapted to leguminous plants or a new begomovirus species. To our knowledge, this is the first report of a begomovirus infecting soybean in Mexico. References: (1) J. T. Ascencio-Ibañez et al. Plant Dis. 86:692, 2002. (2) J. Méndez-Lozano et al. Phytopathology 93:270, 2003.

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A Begomovirus Isolated from Chlorotic and Stunted Soybean Plants in Mexico is a New Strain of Rhynchosia golden mosaic virus

Plant Disease ◽

10.1094/pd-90-0972b ◽

2006 ◽

Vol 90 (7) ◽

pp. 972-972 ◽

Cited By ~ 9

Author(s):

J. Méndez-Lozano ◽

L. L. Perea-Araujo ◽

R. D. Ruelas-Ayala ◽

N. E. Leyva-López ◽

J. A. Mauricio-Castillo ◽

...

Keyword(s):

Mosaic Virus ◽

Dna Sequences ◽

Sequence Similarity ◽

Pcr Amplification ◽

Nucleotide Identity ◽

Degenerate Primers ◽

Viral Dna ◽

Field Samples ◽

Pcr Products ◽

Soybean Plants

Soybean (Glycine max Merr.) is an alternative crop during the summer in Sinaloa, a northern state of Mexico. During the last 4 years, symptoms of yellowing, curled leaves, and stunting have been observed on soybean plantings, and a scrutiny of field samples collected in 2003 identified a begomovirus related to Pepper golden mosaic virus in symptomatic plants (4). A new survey was conducted during the summer of 2004 when the soybean disease was prevalent in the region. Affected plants appeared as patches displaying symptoms ranging from mild to severe yellow mosaic with leaf deformation and stunted growth in several parcels of commercial fields of northern Sinaloa. More than 100 samples from symptomatic soybean plants and weeds growing within the same fields were collected and analyzed for the presence of begomoviruses using DNA hybridization with the coat protein gene of Pepper huasteco yellow vein virus as a probe. Thirty-eight soybean, 12 Rhynchosia sp., and 14 sunflower hybridization-positive samples were subsequently used for polymerase chain reaction (PCR) amplification with the degenerate primers pRep-DGR and pCP70-Mot (1). PCR products were cloned into pGEM-T Easy vector (Promega, Madison, WI) and sequenced. The amplified viral DNA (915 nt) from two soybean plants, Sb1 and Sb2 (GenBank Accession Nos. AY955101 and AY957561, respectively), one isolate from Rhynchosia minima (GenBank Accession No. AY955102), and one from Heliantus annum (GenBank Accession No. AY957560) were sequenced and compared with DNA sequences available at NCBI database using BLAST. The highest sequence similarity was obtained with the two known isolates of Rhynchosia golden mosaic virus, RhGMV [Honduras] (GenBank Accession No. AF239671), and RhGMV [Chiapas] (GenBank Accession No. AF408199), displaying a nucleotide identity of approximately 89% with the Sinaloa isolates. Sequence comparisons of the latter isolates showed that viruses in the weeds were 97% identical to one of the soybean isolates, RhGMV-Sb1, but differed significantly (88% of nucleotide identity) from the second soybean isolate, RhGMV-Sb2. The complete genome A sequence of RhGMV-Sb1 was determined using PCR amplification of viral DNA with four degenerate primers recently described (2), cloning of overlapping PCR products into pGEM-T Easy vector (Promega) and sequencing. The 2,604-bp DNA-A of RhGMV-Sb1 (GenBank Accession No. DQ347950) was compared with the homologous genome of RhGMV [Chiapas] and RhGMV [Honduras] using the CLUSTAL alignment method (MegAlign, DNASTAR software, London) and an overall nucleotide identity of 89.2 and 88.6%, respectively, was determined. Current taxonomic criteria for begomoviruses establish that a DNA-A sequence identity lower than 93% with other isolates of a virus is indicative of a separate strain (3). Therefore, the virus identified in this study is a new strain of RhGMV that is provisionally named Rhynchosia golden mosaic virus-Soybean [Mexico:Sinaloa:2004]. This is the first soybean-infecting begomovirus from the American continent whose genome A has been completely characterized as of today. References: (1) J. T. Ascencio-Ibañez et al. Plant Dis. 86:692, 2002. (2) R. De La Torre-Almaraz et al. Plant Dis. 90:378, 2006. (3) C. Fauquet et al. Arch. Virol. 150:2151, 2005. (4) J. Mendez-Lozano et al. Plant Dis. 90:109, 2006.

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Tropical soda apple mosaic virus Identified in Solanum capsicoides in Florida

Plant Disease ◽

10.1094/pdis-91-9-1204a ◽

2007 ◽

Vol 91 (9) ◽

pp. 1204-1204 ◽

Cited By ~ 2

Author(s):

S. Adkins ◽

G. McAvoy ◽

E. N. Rosskopf

Keyword(s):

Sequence Analysis ◽

Mosaic Virus ◽

Sandwich Elisa ◽

Tomato Mosaic Virus ◽

Rt Pcr ◽

Degenerate Primers ◽

Lee County ◽

Cp Gene ◽

Local Lesions ◽

Tropical Soda Apple

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.

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First Report of Cymbidium mosaic virus and Odontoglossum ringspot virus in Orchids in Mexico

Plant Disease ◽

10.1094/pdis-08-11-0655 ◽

2012 ◽

Vol 96 (3) ◽

pp. 464-464

Author(s):

A. G. Soto-Valladares ◽

R. De La Torre-Almaraz ◽

B. Xoconostle-Cazares ◽

R. Ruíz-Medrano

Keyword(s):

Mosaic Virus ◽

Pcr Amplification ◽

Positive Sample ◽

Ringspot Virus ◽

Rdrp Gene ◽

Mixed Infections ◽

Cymbidium Mosaic Virus ◽

First Report ◽

Odontoglossum Ringspot Virus ◽

Cp Gene

In 2010, a survey for viral diseases in commercial, orchid-producing greenhouses was carried out in Morelos, Mexico. Many symptomatic plants were observed. The most common leaf symptoms were yellow mottle, yellow streaks, and chlorotic and necrotic ringspots. Leaf samples were collected from eight symptomatic plants from the following genera: Encyclia, Oncidium, Shomburghia, Brassia, Guarianthe, Cattleya, Epidendrum, Vanilla, Xilobium, Laelia, and Brassocattleya. Samples were tested using double-antibody sandwich (DAS)-ELISA (Agdia, Elkhart, IN) with antiserum for Cymbidium mosaic virus (CymMV), Odontoglossum ringspot virus (ORSV), Cymbidium ringspot mosaic virus, and Tobacco mosaic virus (TMV) and a general antiserum for potyviruses. At least one plant from each genus was positive to CymMV and ORSV as individual or mixed infections. Encyclia and Laelia plants were the most frequently found with mixed infections by both viruses. All genera were negative for TMV and potyviruses. Total RNA extracts were obtained from all ELISA-positive samples by a modified silica capture protocol (2). Reverse transcription (RT)-PCR was carried out with general polymerase (RdRp) gene primers corresponding to the Potexvirus group (3) and specific primers for the coat protein gene (CP) of CymMV and ORSV (1). The PCR amplification from a positive sample of each genus was resolved in agarose gels. Amplification products of the expected size were obtained for CymMV and ORSV. Five CymMV RdRp gene clones from five different plants of Laelia (GenBank Accession Nos. HQ393958, HQ393959, HQ393960, HQ393961, and HQ393962), two CP gene clones of CP gene of CymMV from two different plants of Oncidium (GenBank Accession Nos. HQ393956 and HQ393957), and three CP clones of CP of ORSV from three different plants of Encyclia (GenBank Accession Nos. HQ393953, HQ393954, and HQ393955) were sequenced. The nucleotide sequences of the Mexican orchid CymMV isolates were 96 to 97% identical to CymMV sequences in the GenBank, while those of ORSV were 99 to 100% identical to deposited ORSV sequences. To our knowledge, this is the first report of CymMV and ORSV in orchids in Mexico, which are two of the most important quarantine virus in orchids in Mexico. References: (1) P. Ajjikuttira et al. J. Gen. Virol. 86:1543, 2005. (2) J. R. Thompson et al. J. Virol. Methods 111:85, 2003. (3) R. A. A. van der Vlugt and M. Berendsen. Eur. J. Plant Pathol. 108:367, 2002.

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Genetic Diversity Among Geminiviruses Associated with the Weed Species Sida spp., Macroptilium lathyroides, and Wissadula amplissima from Jamaica

Plant Disease ◽

10.1094/pdis.1997.81.11.1251 ◽

1997 ◽

Vol 81 (11) ◽

pp. 1251-1258 ◽

Cited By ~ 40

Author(s):

Marcia E. Roye ◽

Wayne A. McLaughlin ◽

Medhat K. Nakhla ◽

Douglas P. Maxwell

Keyword(s):

Genetic Diversity ◽

Amino Acid ◽

Mosaic Virus ◽

Amino Acid Sequences ◽

Yellow Mosaic Virus ◽

Weed Species ◽

Degenerate Primers ◽

Sequence Comparisons ◽

The Common ◽

Macroptilium Lathyroides

Genetic diversity among geminiviruses associated with three common weeds in Jamaica was studied using digoxigenin-labeled geminiviral DNA probes, polymerase chain reaction with degenerate primers for DNA-A and DNA-B, nucleic acid sequencing, and derived amino acid sequences. Geminiviruses with bipartite genomes were found in Sida spp., Macroptilium lathyroides, and Wissadula amplissima. The geminiviruses detected in Sida spp. and M. lathyroides were nearly identical and were both designated Sida golden mosaic geminivirus (SidGMV-JA), whereas the geminivirus in W. amplissima was sufficiently different to be designated Wissadula golden mosaic geminivirus (WGMV). Nucleotide sequence comparisons of the common regions and the N-terminal regions of the AC1 (rep) and AV1 ORFs, together with the derived amino acid sequence comparisons of the N-terminal parts of BC1 and BV1 ORFs were used to determine their similarities to other geminiviruses. SidGMV-JA was most similar to potato yellow mosaic geminivirus (PYMV). We propose that these two geminiviruses (SidGMV-JA and PYMV) define a new geminivirus cluster, the potato yellow mosaic virus (PYMV) cluster. WGMV was most similar to members of the Abutilon mosaic virus cluster but is not likely to be included in the Abutilon phylogenetic group because of the divergent sequence of the common region. These results indicate that geminiviruses infecting some weeds in Jamaica are distinct from crop-infecting geminiviruses in Jamaica and define a new geminivirus cluster.

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Characterization of Two Distinct Pepino Mosaic Virus Isolates from Tomato in Lithuania

Botanica Lithuanica ◽

10.2478/botlit-2013-0003 ◽

2013 ◽

Vol 19 (1) ◽

pp. 22-27

Author(s):

Marija Žižytė ◽

Donatas Šneideris ◽

Irena Zitikaitė ◽

Laima Urbanavičienė ◽

Juozas Staniulis

Keyword(s):

Sequence Analysis ◽

Coat Protein ◽

Mosaic Virus ◽

Gene Sequence ◽

Pepino Mosaic Virus ◽

Tomato Plants ◽

Cp Gene ◽

Gene Sequence Analysis ◽

Virus Isolates

Abstract Two isolates of Pepino mosaic virus (PepMV) from tomato plants grown in different commercial greenhouses in Lithuania were characterized by coat protein (CP) gene sequence analysis. Comparison with other PepMV isolates from the GenBank database showed that both Lithuanian PepMV isolates share 78.3% nucleotide identity and belong to two distinct EU and CH2 genotypes of PepMV. This is the first report on characterization of two PepMV genotypes detected in Lithuania.

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Characteristic of Tobacco mosaic virus isolated from cucumber and tobacco collected from East Java, Indonesia

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d201023 ◽

2019 ◽

Vol 20 (10) ◽

Cited By ~ 1

Author(s):

LISTIHANI ◽

SRI HENDRASTUTI HIDAYAT ◽

SURYO WIYONO ◽

Tri Asmira Damayanti

Keyword(s):

Phylogenetic Analysis ◽

Amino Acid ◽

Nucleic Acid ◽

Coat Protein ◽

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Protein Gene ◽

Cp Gene ◽

Emerging Virus ◽

Tomato Isolate

Abstract. Listihani, Hidayat SH, Wiyono S, Damayanti TA. 2019. Characteristic of Tobacco mosaic virus isolated from cucumber and tobacco collected from East Java, Indonesia. Biodiversitas 20: 2937-2942. Tobacco mosaic virus (TMV) is a newly emerging virus infecting cucumbers in Java, Indonesia. The basic characters of the TMV isolated from cucumber need further study to investigate its differences with that from tobacco. Thus, the research aimed to study the character of both isolates based on their biological, symptomatology and nucleic acid of coat protein (CP) gene properties. The TMV isolates from both cucumber and tobacco were able to infect similar indicator plants with differing symptom expressions, especially on eggplant. Homology of nucleotide and amino acid of coat protein gene among isolates were about 90.3% and 91.0%, and homology to other isolates was about 87.6 to 93.8% and 89.3 to 96.8%, respectively. There were 17 amino acid differences in the CP gene which is presumed to differentiate those two isolates. Phylogenetic analysis CP gene sequences compared with corresponding isolates in GenBank showed the two isolates separated in different clades. The cucumber isolate from Kediri is closely related to tomato isolate from China in clade I, while tobacco isolate from Jember closely related to tobacco isolate from China in clade IIindicating the existence of two differ TMV variants. It will increase the difficulty to manage TMV in the fields.

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First Report of Bean yellow mosaic virus in Alaska from Clover (Trifolium spp.)

Plant Disease ◽

10.1094/pdis-94-3-0372a ◽

2010 ◽

Vol 94 (3) ◽

pp. 372-372 ◽

Cited By ~ 1

Author(s):

N. L. Robertson ◽

K. L. Brown

Keyword(s):

Coat Protein ◽

Host Range ◽

Mosaic Virus ◽

Bean Yellow Mosaic Virus ◽

Yellow Mosaic Virus ◽

Degenerate Primers ◽

First Report ◽

Chlorotic Spot ◽

Putative Coat Protein ◽

Das Elisa

In mid-June 2008, distinct mosaic leaves were observed on a cluster of clover (Trifolium spp.) with light pink and white flowers growing at the edge of a lawn in Palmer, AK. Virus minipurification from leaves of affected clover and protein extractions on a polyacrylamide electrophoresis implicated a ~35-kDa putative coat protein (CP). Subsequent western blots and ELISA with a universal potyvirus antiserum (Agdia Inc., Elkhart, IN) confirmed potyvirus identity. Total RNA extracts (RNeasy Plant Mini Kit, Qiagen Inc., Valencia, CA) from the same plant were used for reverse transcription (RT)-PCR. Three sets of degenerate primers that targeted potyvirus-specific genes, HC-Pro (helper component protease) and CI (cylindrical inclusion protein) and the genomic 3′-terminus that included a partial NIb (nuclear inclusion), CP (coat protein), and UTR (untranslated region), produced the expected PCR segments (~0.7, ~0.7, and ~1.6 kbp, respectively) on 1% agarose gels (1). Direct sequencing of the HC-Pro (GenBank No. GQ181115), CI (GQ181116), and CP (GU126690) segments revealed 98, 97, and 99% nucleotide identities (no gaps), respectively, to Bean yellow mosaic virus (BYMV)-chlorotic spot (CS) strain, GenBank No. AB373203. The next closest BYMV percent identity comparisons decreased to 79% for HC-Pro (GenBank No. DQ641248; BYMV-W), 79% for CI (U47033; BYMV-S) partial genes, and 96% for CP (AB041971; BYMV-P242). Mechanical inoculations of purified virus preparations produced local lesions on Chenopodium amaranticolor Coste & A. Reyn. (2 of 5) and C. quinoa Willd. (6 of 7), and mosaic on Nicotiana benthamiana Domin (5 of 5). BYMV was specifically confirmed on tester plants using a double-antibody sandwich (DAS)-ELISA BYMV (strain 204 and B25) kit (AC Diagnostics, Inc., Fayetteville, AR) as directed. The absence of another potyvirus commonly found in clover, Clover yellow vein virus (ClYVV), was verified in parallel DAS-ELISA ClYVV assays (AC Diagnostics, Inc). The BYMV isolate was maintained in N. benthamiana, and virion or sap extracts inoculated to the following host range (number of infected/total inoculated plants [verified by BYMV ELISA]): Cucumis sativus L. ‘Straight Eight’ (0/5), Gomphrena globosa L. (1/4), Nicotiana clevelandii A. Gray (4/7), Phaseolus vulgaris L. ‘Bountiful’ (1/3), Pisum sativum L. (Germplasm Resources Information Network Accession Nos. -PI 508092 (8/12), -W6 17525 (13/13), -W6 17529 (0/13), -W6 17530 (13/14), -W6 17537 (0/12), -W6 17538 (0/12), and -W6 17539 (0/21), Tetragonia tetragoniodes (2/2), Trifolium pretense L. ‘Altaswede’ (6/10), T. repens L. ‘Pilgrim’ (0/8), and Vicia faba L. (1/3). All infected plants had symptoms ranging from systemic mosaic (T. pretense, P. sativum) to leaf distortions (N. clevelandii, Tetragonia tetragoniodes). Interestingly, the host range and genomic sequences of the BYMV Alaskan strain resemble the BYMV-CS (chlorotic spot) strain that was originally isolated from a diseased red clover (T. pretense) plant in Japan more than 40 years ago (2). Although BYMV occurs worldwide and has a wide host range in dictoyledonous and monocotyledonous plants (3), to our knowledge, this is the first report of a natural occurrence of BYMV in Alaska. The incidence and distribution of BYMV in clover and other plant species are not known in Alaska. References: (1) C. Ha et al. Arch. Virol. 153:36, 2008. (2) H. Kume et al. Mem. Fac. Agric. Hokkaido Univ. 7:449, 1970. (3) S. J. Wylie et al. Plant Dis. 92:1596, 2008.

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Effectiveness of coat protein and defective replicase gene-mediated resistance against Australian isolates of cucumber mosaic virus

Australian Journal of Experimental Agriculture ◽

10.1071/ea96097 ◽

1998 ◽

Vol 38 (4) ◽

pp. 375 ◽

Cited By ~ 6

Author(s):

Z. Singh ◽

M. G. K. Jones ◽

R. A. C. Jones

Keyword(s):

Coat Protein ◽

Transgenic Plants ◽

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Transgenic Tobacco ◽

Extreme Resistance ◽

Tobacco Plants ◽

Systemic Movement ◽

Cp Gene ◽

Subgroup Ii

Summary. Transgenic tobacco (Nicotiana tabacum) plants of (i) cv. Samsun NN containing the cauliflower mosaic virus 35S constitutive promoter linked to a defective replicase (DR) gene derived from cucumber mosaic virus (CMV) subgroup I isolate Fny, and (ii) cv. Xanthi containing the CaMV 35S promoter linked to the coat protein (CP) gene of CMV subgroup I isolate C were tested for resistance to various Australian isolates of CMV. The tobacco plants were challenged with 3 CMV subgroup 1 isolates (BNRR, BMR and B6) using sap inoculation. When used to challenge non-transgenic tobacco plants with 5 subgroup II CMV isolates from lupins (LY, LCH, LAcc, LGu and LD), this inoculation method did not result in systemic infection so graft inoculation was used instead to challenge transgenic plants with these 5 isolates. When plants of the line with the DR gene were challenged with the 3 subgroup I isolates, extreme resistance was revealed as none showed symptoms and CMV was not detectable by ELISA. When the same 3 isolates were inoculated to the 3 lines with the CP gene, resistance was characterised by fewer plants becoming virus infected, delayed systemic movement and, in the plants that were infected, partial remission of symptoms plus somewhat decreased virus concentration. Challenge of transgenic plants with DR or CP with the 5 subgroup II isolates resulted in fewer plants becoming infected. Actual numbers of plants infected varied with line and subgroup II isolate and the DR gene was as effective as the CP gene at decreasing infection. With subgroup II isolate LY, infection was associated with remission of symptoms and with the other 4 isolates with delayed systemic movement. Thus the DR gene approach was more effective than the CP approach in obtaining extreme resistance against Australian subgroup I isolates of CMV. These results suggest that introducing a similar DR gene construct made from a subgroup II isolate from lupins into commercial lupin cultivars may be a suitable strategy for obtaining extreme resistance to subgroup II isolates from lupins.

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Bean common mosaic virus and Bean common mosaic necrosis virus in Mexico

Plant Disease ◽

10.1094/pdis.2003.87.1.21 ◽

2003 ◽

Vol 87 (1) ◽

pp. 21-25 ◽

Cited By ~ 28

Author(s):

N. Flores-Estévez ◽

J. A. Acosta-Gallegos ◽

L. Silva-Rosales

Keyword(s):

Coat Protein ◽

Mosaic Virus ◽

Coat Protein Gene ◽

Protein Gene ◽

Bean Common Mosaic Virus ◽

Nucleotide Sequences ◽

Necrosis Virus ◽

Cp Gene

A survey was performed in Mexico to study the distribution of Bean common mosaic virus (BCMV) and Bean common mosaic necrosis virus (BCMNV) using a set of primers directed to the coat protein gene (CP) that were designed to detect and characterize the two viral species. Both viral species were present in different locations in the country. BCMV was predominant in the central states of the country, whereas BCMNV proliferated toward the eastern tropical states. The alignment of nine nucleotide sequences for each viral species at the amino region of the CP gene confirmed the identities of the viruses and set the basis to assign them tentatively to pathogroups I, II, and VI.

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The Cylindrical Inclusion Gene of Turnip mosaic virus Encodes a Pathogenic Determinant to the Brassica Resistance Gene TuRB01

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2000.13.10.1102 ◽

2000 ◽

Vol 13 (10) ◽

pp. 1102-1108 ◽

Cited By ~ 82

Author(s):

C. E. Jenner ◽

F. Sánchez ◽

S. B. Nettleship ◽

G. D. Foster ◽

F. Ponz ◽

...

Keyword(s):

Mosaic Virus ◽

Spontaneous Mutation ◽

Turnip Mosaic Virus ◽

Site Directed Mutagenesis ◽

Cylindrical Inclusion ◽

Spontaneous Mutant ◽

Coding Region ◽

Region Gene ◽

Sequence Comparisons ◽

Cp Gene

The viral component of Turnip mosaic virus (TuMV) determining virulence to the Brassica napus TuRB01 dominant resistance allele has been identified. Sequence comparisons of an infectious cDNA clone of the UK 1 isolate of TuMV (avirulent on TuRB01) and a spontaneous mutant capable of infecting plants possessing TuRB01 suggested that a single nucleotide change in the cylindrical inclusion (CI) protein coding region (gene) of the virus was responsible for the altered phenotype. A second spontaneous mutation involved a different change in the CI gene. The construction of chimeric genomes and subsequent inoculations to plant lines segregating for TuRB01 confirmed the involvement of the CI gene in this interaction. Site-directed mutagenesis of the viral coat protein (CP) gene at the ninth nucleotide was carried out to investigate its interaction with TuRB01. The identity of this nucleotide in the CP gene did not affect the outcome of the viral infection. Both mutations identified in the CI gene caused amino acid changes in the C terminal third of the protein, outside any of the conserved sequences reported to be associated with helicase or cell-to-cell transport activities. This is the first example of a potyvirus CI gene acting as a determinant for a genotype-specific resistance interaction.

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