Co-infection of Beet mosaic virus with Beet Yellowing Viruses Leads to Increased Symptom Expression on Sugar Beet

Three distinct aphid-transmitted viruses associated with a yellowing disease on sugar beet were examined in single and mixed infections for the effects of virus interactions on plant weight, rate of symptom development, and virus concentration. Sugar beet lines exhibiting different degrees of susceptibility to the virus yellows complex were inoculated with either one, two, or all three viruses. Severe stunting, as measured by fresh plant biomass, was observed with mixed infections with Beet yellows virus (BYV) and Beet mosaic virus (BtMV), compared to single infections of these viruses. In addition, the overall rate of appearance of Beet western yellows virus (BWYV) symptoms increased during co-infection with BtMV. Synergistic effects on stunting severity, as measured by plant biomass, were more pronounced in susceptible beet lines, but similar patterns also were observed in lines exhibiting tolerance to virus yellows. Relative concentrations of viruses were compared among single and mixed infections using dot-blot hybridization with virus specific probes, and quantified by phosphorimage analysis. Titers of all three viruses increased as a result of co-infection compared with single infections.

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Sugar Beet Performance with Curly Top Is Related to Virus Accumulation and Age at Infection

Plant Disease ◽

10.1094/pd-90-0657 ◽

2006 ◽

Vol 90 (5) ◽

pp. 657-662 ◽

Cited By ~ 15

Author(s):

William M. Wintermantel ◽

Stephen R. Kaffka

Keyword(s):

Sugar Beet ◽

Management Practices ◽

Effective Means ◽

Field Trials ◽

Virus Concentration ◽

Multiple Traits ◽

Higher Plant ◽

Plant Weight ◽

Virus Accumulation ◽

Greenhouse Assay

Resistance to curly top disease caused by Beet curly top virus (BCTV) and related curtoviruses has been important to sustainable sugar beet (Beta vulgaris) production in the western United States for most of the last century. Recent advances in sugar beet genetics have led to the development of high-yielding cultivars, but these cultivars have little resistance to curly top disease. These cultivars are highly effective when disease management practices or environmental factors minimize curly top incidence, but can result in significant losses in years with early infection or abundant curly top. A greenhouse assay has been developed to rapidly test cultivars for a broad array of factors affecting performance in the presence of curly top. Previous studies have shown that sugar beet plants were more susceptible and losses more severe when seedlings were infected by BCTV, but less severe when plants were larger at the time of infection. To evaluate more precisely the relationship between age at infection, disease severity, virus accumulation, and yield loss in modern cultivars that were not bred for curly top resistance, individual sugar beet plants varying in degree of resistance and susceptibility to curly top were inoculated by viruliferous beet leafhoppers (Circulifer tenellus) when plants had two, four, or six true leaves, and maintained in a greenhouse for 6 weeks. When plants were inoculated at the two-leaf stage, all cultivars became severely stunted, with high disease ratings and similar rates of symptom development, regardless of resistance or susceptibility of the cultivar. Plants inoculated at four-and six-leaf stages exhibited increasing separation between resistant and susceptible phenotypes, with highly resistant cultivars performing well with low disease ratings and increased plant weights relative to susceptible cultivars. High-yielding cultivars performed only slightly better than the susceptible control cultivar. Results from greenhouse trials matched those from field trials conducted under heavy curly top pressure. Importantly, low virus concentration was directly correlated with lower disease ratings and higher plant weight, while elevated virus concentrations corresponded to higher disease ratings and lower weights. This demonstrates that a rapid greenhouse assay involving multiple traits can provide a rapid and effective means of selecting cultivars with improved curly top control, and could lead to more rapid incorporation of resistance into high-yielding sugar beet.

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Detection of Two Bipartite Geminiviruses Infecting Dicotyledonous Weeds in Trinidad

Plant Disease ◽

10.1094/pdis.2003.87.5.602a ◽

2003 ◽

Vol 87 (5) ◽

pp. 602-602 ◽

Cited By ~ 5

Author(s):

S. N. Rampersad ◽

P. Umaharan

Keyword(s):

Mosaic Virus ◽

Large Scale ◽

Blot Hybridization ◽

Yellow Mosaic Virus ◽

Leaf Margin ◽

Weed Species ◽

Dot Blot ◽

Leaf Extracts ◽

Degenerate Primers ◽

Sequence Comparisons

Severe symptoms of suspected geminivirus etiology were manifested as intense yellow or golden mottling or mosaic of the lamina accompanied by mild leaf margin distortion on dicotyledonous weed species, Sida rhombifolia (L.) and Rhynchosia minima (L.), collected from 1999 to 2002 from the northeastern and central regions of Trinidad. S. rhombifolia is a common roadside weed while R. minima may have been introduced through restricted cultivation as a forage legume for livestock. Potato yellow mosaic virus-Trinidad isolate (PYMV-TT) has been implicated as the primary causal agent of begomoviral disease in large-scale tomato cultivation in Trinidad (2). It has been suggested that these weeds may be alternative hosts to PYMV-TT. However, all samples tested negative for PYMV-TT in dot blot hybridization assays using a PYMV-TT-specific DNA-A probe under high stringency. These results excluded the presence of PYMV-TT in these weeds. Polymerase chain reaction (PCR) amplification using clarified leaf extracts with degenerate primers for DNA-A (MP16 and MP82, PAL1v1978 and PAR1c715, and prV324 and prC889) and for DNA-B (PBL1v2040 and PCRc1) was performed on the weed samples (S. N. Rampersad and P. Umaharan, unpublished). Degenerate primers MP16 and MP82 target the 5′ terminal region of the coat protein (cp) (2); PAL1v1978 and PAR1c715 direct amplification of the replication-associated protein gene (rep) and part of the cp gene (1); prV324 and prC889 amplify the core cp sequence (3). Primers PBL1v2040 and PCRc1 target the intergenic region and the 5′ terminal of the BL1 ORF (1). PCR fragments obtained through amplification using this primer pair confirmed the presence of a DNA-B component for the unknown viruses. PCR fragments were sequenced and alignments were performed using DNASTAR (DNASTAR Inc., Madison, WI) and BLASTN ( www.ncbi.nlm.nih.gov/blast/ ) programs. None of the partial nucleotide sequences obtained for the viruses produced significant alignments with each other (5′ terminal cp: 74% identity; core cp sequence: 78% identity), suggesting the detection of two distinct viruses. In addition, the partial sequences obtained were aligned to sequences of homologous regions of 11 New World begomoviruses (from the major representative clusters). The nearest match for R. minima, using alignments with 5′ terminal cp (GenBank Accession No. AY221124), core cp (GenBank Accession No. AY217344), and 5′ terminal BL1 region (GenBank Accession No. AY220490) was obtained for Rhynchosia golden mosaic virus (RhGMV, GenBank Accession Nos. AF408199 and AF442117) with 84 and 88% identity. There were no significant similarities found for sequence comparisons of the BL1 ORF. For S. rhombifolia, the highest homology using the 5′ terminal cp (GenBank Accession No. AY220489), core cp (GenBank Accession No. AY217345), rep/cp region (GenBank Accession No. AY220488), and the 5′ terminal BL1 region (GenBank Accession No. AY221125) was obtained for Sida golden mosaic virus (SiGMV, GenBank Accession Nos. AF049336, AF070923, and Y11100), with 82, 89, 84, and 87% identity. To our knowledge, this is the first report of geminivirus infection in these weed species in Trinidad. This may have substantial implications to future geminivirus disease outbreaks especially if there is expansion of the host range of these viruses to include economically important crops. References: (1) M. R. Rojas et al. Plant Dis. 77:340, 1993. (2) P. Umaharan et al. Phytopathology 88:1262, 1998. (3) S. D. Wyatt and J. K. Brown. Phytopathology 86:1288, 1996.

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Zantedeschia mild mosaic virus, a new widespread virus in calla lily, detected by ELISA, dot-blot hybridization and IC-RT-PCR

Plant Pathology ◽

10.1111/j.1365-3059.2006.01485.x ◽

2007 ◽

Vol 56 (1) ◽

Cited By ~ 7

Author(s):

C.-H. Huang ◽

W.-C. Hu ◽

T.-C. Yang ◽

Y.-C. Chang

Keyword(s):

Mosaic Virus ◽

Blot Hybridization ◽

Mild Mosaic ◽

Rt Pcr ◽

Dot Blot ◽

Dot Blot Hybridization ◽

Calla Lily ◽

Mild Mosaic Virus

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Identification of Resistance to Potato yellow mosaic virus-Trinidad Isolate (PYMV-TT) Among Lycopersicon Species

Plant Disease ◽

10.1094/pdis.2003.87.6.686 ◽

2003 ◽

Vol 87 (6) ◽

pp. 686-691 ◽

Cited By ~ 7

Author(s):

S. N. Rampersad ◽

P. Umaharan

Keyword(s):

Mosaic Virus ◽

Germ Plasm ◽

Blot Hybridization ◽

Yellow Mosaic Virus ◽

Dot Blot ◽

Breeding Lines ◽

Dot Blot Hybridization ◽

Lycopersicon Species ◽

Commercial Cultivars ◽

Leaf Curl Virus

Three studies were carried out with the objective of identifying resistance to Potato yellow mosaic virus-Trinidad isolate (PYMV-TT) among Lycopersicon species through field screening and using field-inoculated infector rows. The presence of PYMV-TT was confirmed using dot blot hybridization assays. In the first study, eight commercial cultivars of tomato were tested for resistance. In a subsequent study, 11 breeding lines showing high levels of resistance to Tomato mottle virus (ToMoV-Florida) and six lines resistant to Tomato yellow leaf curl virus (TYLCV-Old World Begomovirus) were screened for resistance to PYMV-TT. All breeding lines and the commercial cultivars tested were susceptible to PYMV-TT infection. The third study involved screening 92 accessions from a representative core collection of wild Lycopersicon germ plasm. PYMV-TT was not detected in individuals of 22 accessions.

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First Report of Tomato torrado virus Infecting Tomato in Hungary

Plant Disease ◽

10.1094/pdis-93-5-0554c ◽

2009 ◽

Vol 93 (5) ◽

pp. 554-554 ◽

Cited By ~ 18

Author(s):

A. Alfaro-Fernández ◽

G. Bese ◽

C. Córdoba-Sellés ◽

M. C. Cebrián ◽

J. A. Herrera-Vásquez ◽

...

Keyword(s):

Coat Protein ◽

Mosaic Virus ◽

Polyclonal Antibodies ◽

Blot Hybridization ◽

Sandwich Elisa ◽

World Intellectual Property Organization ◽

Tomato Mosaic Virus ◽

Rt Pcr ◽

Dot Blot ◽

First Report

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.

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Pepper huasteco virus and Pepper golden mosaic virus are Geminiviruses Affecting Tomatillo (Physalis ixocarpa) Crops in Mexico

Plant Disease ◽

10.1094/pdis.2001.85.12.1291a ◽

2001 ◽

Vol 85 (12) ◽

pp. 1291-1291 ◽

Cited By ~ 6

Author(s):

J. Méndez-Lozano ◽

R. F. Rivera-Bustamante ◽

C. M. Fauquet ◽

R. De la Torre-Almaraz

Keyword(s):

Mosaic Virus ◽

Blot Hybridization ◽

Amino Acid Level ◽

Dot Blot ◽

Stem Loop ◽

Horticultural Crops ◽

Hybridization Procedure ◽

Pcr Products ◽

Main Production ◽

Production Areas

Whitefly-transmitted geminivirus diseases cause important losses in several horticultural crops in all areas in Mexico (1). Tomatillo is important in the Mexican diet since it is widely used to prepare many types of salsas and other dishes. As a result, tomatillo, also known as tomate verde (green tomato), is cultivated in 29 of 32 states in Mexico, with the main production areas located in the states of Morelos, Puebla, and Michoacán. Leaf samples of 105 tomatillo plants exhibiting yellowing, yellowing mosaic, leaf curl, bunchy top, and stunting were collected from the states of Puebla, Morelos, Estado de México, and Sinaloa. Symptomatic plants were associated with the presence of whiteflies in many fields and suggested a viral etiology. Total DNA extracted from symptomatic tomatillo plants was used as a template in a polymerase chain reaction (PCR)-based geminivirus detection procedure. MP16 and MP82 primers (2) were used to direct the amplification of a segment from the stem-loop structure in the intergenic region (IR) to a conserved region in the coat protein (CP) of begomoviruses (2). Sixty-nine percent (72/105) of the samples produced the expected PCR fragment (400 to 450 bp). Similar results were obtained with a dot-blot hybridization procedure using as a probe the component A of Pepper huasteco virus (PHV) under low stringency conditions. More than 50 PCR products were cloned and sequenced. Sequence analysis (nucleotide level for the IR; amino acid level for the CP) revealed that the tomatillo-infecting geminiviruses clustered into two main groups. The first group showed a high percent identity (average of 95.3% at the CP N terminus) to PHV, whereas the second showed a similarly high percent (average 93.8%) identity to Pepper golden mosaic virus (PepGMV, previously called Texas pepper geminivirus. Both PepGMV and PHV were found in all sampled areas. Although mixed infections (differentiated by the respective IR probes) of PHV and PepGMV were common (61%), single infections were also detected (PHV 27%; PepGMV 10%). The presence of begomoviruses in tomatillo crops has been previously reported (1); however, their identity as PHV and PepGMV was not confirmed. References: (1) I. Torres-Pacheco et al. Phytopathology 86:1186, 1996. (2) P. Umaharan et al. Phytophatology 88:1262, 1998.

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Interactions Between Beet necrotic yellow vein virus and Beet soilborne mosaic virus in Sugar Beet

Plant Disease ◽

10.1094/pdis.2003.87.10.1170 ◽

2003 ◽

Vol 87 (10) ◽

pp. 1170-1175 ◽

Cited By ~ 24

Author(s):

G. C. Wisler ◽

R. T. Lewellen ◽

J. L. Sears ◽

J. W. Wasson ◽

H.-Y. Liu ◽

...

Keyword(s):

Sugar Beet ◽

Mosaic Virus ◽

Seedling Emergence ◽

Yellow Vein ◽

Enzyme Linked Immunosorbent Assay ◽

Mixed Infections ◽

Polymyxa Betae ◽

Susceptible Cultivar ◽

Fresh Weight ◽

Virus Content

Soils naturally infested with cultures of aviruliferous Polymyxa betae and viruliferous P. betae carrying two sugar beet benyviruses, Beet necrotic yellow vein virus (BNYVV) and Beet soilborne mosaic virus (BSBMV), alone and in combination, were compared with noninfested soil for their effects on seedling emergence, plant fresh weight, and virus content as measured by enzyme-linked immunosorbent assay (ELISA). Studies examined sugar beet with and without resistance to the disease rhizomania, caused by BNYVV. The Rz gene, conferring resistance to BNYVV, did not confer resistance to BSBMV. BSBMV ELISA values were significantly higher in single infections than in mixed infections with BNYVV, in both the rhizomania-resistant and -susceptible cultivars. In contrast, ELISA values of BNYVV were high (8 to 14 times the healthy mean) in single and mixed infections in the rhizomania-susceptible cultivar, but were low (approximately three times the healthy mean) in the rhizomania-resistant cultivar. Results indicate BNYVV may suppress BSBMV in mixed infections, even in rhizomania-resistant cultivars in which ELISA values for BNYVV are extremely low. Soils infested with P. betae, and with one or both viruses, showed significantly reduced fresh weight of seedlings, and aviruliferous P. betae significantly decreased sugar beet growth in assays.

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Yellowing Disease in Zucchini Squash Produced by Mixed Infections of Cucurbit yellow stunting disorder virus and Cucumber vein yellowing virus

Phytopathology ◽

10.1094/phyto-12-10-0343 ◽

2011 ◽

Vol 101 (11) ◽

pp. 1365-1372 ◽

Cited By ~ 16

Author(s):

Francisco M. Gil-Salas ◽

Jeff Peters ◽

Neil Boonham ◽

Isabel M. Cuadrado ◽

Dirk Janssen

Keyword(s):

Synergistic Effects ◽

Zucchini Yellow Mosaic Virus ◽

Virus Titer ◽

Yellow Mosaic Virus ◽

Mixed Infections ◽

Severe Stunting ◽

Yellowing Disease ◽

Leaf Deformation ◽

Chlorotic Mottling ◽

Yellowing Virus

Zucchini squash is host to Cucurbit yellow stunting disorder virus (CYSDV), a member of the genus Crinivirus, and Cucumber vein yellowing virus (CVYV), a member of the genus Ipomovirus, both transmitted by the whitefly Bemisia tabaci. Field observations suggest the appearance of new symptoms observed on leaves of zucchini squash crops when both viruses were present. When infected during controlled experiments with CYSDV only, zucchini plants showed no obvious symptoms and the virus titer decreased between 15 and 45 days postinoculation (dpi), after which it was no longer detected. CVYV caused inconspicuous symptoms restricted to vein clearing on some of the apical leaves and the virus accumulated progressively between 15 and 60 dpi. Similar accumulations of virus followed single inoculations with the potyvirus Zucchini yellow mosaic virus (ZYMV) and plants showed severe stunting, leaf deformation, and mosaic yellowing. However, in mixed infections with CYSDV and CVYV, intermediate leaves showed chlorotic mottling which evolved later to rolling, brittleness, and complete yellowing of the leaf lamina, with exception of the veins. No consistent alteration of CVYV accumulation was detected but the amounts of CYSDV increased ≈100-fold and remained detectable at 60 dpi. Such synergistic effects on the titer of the crinivirus and symptom expression were not observed when co-infected with ZYMV.

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Detection of Hepatitis a Virus and other Enteroviruses in Wastewater and Surface Water Samples by Gene Probe Assay

Water Science & Technology ◽

10.2166/wst.1991.0071 ◽

1991 ◽

Vol 24 (2) ◽

pp. 267-272 ◽

Cited By ~ 12

Author(s):

S. Dubrou ◽

H. Kopecka ◽

J. M. Lopez Pila ◽

J. Maréchal ◽

J. Prévot

Keyword(s):

Surface Water ◽

Cell Cultures ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Limit Of Detection ◽

Blot Hybridization ◽

Noncoding Region ◽

Gene Probe ◽

Dot Blot ◽

Lower Efficiency

Enteroviruses were specifically detected by dot blot hybridization when using poliovirus type 1 (PV1) derived subgenomic radiolabeled cRNA probes (riboprobes) in environmental water specimens and in the cell cultures in which the viruses were amplificated. The riboprobe corresponding to the 5' noncoding sequence detected the majority of enteroviruses. Hepatitis A virus (HAV) was specifically detected by an HAV cRNA probe corresponding to the 5' noncoding region of its genome. By this test, the limit of detection of coxsackievirus B5 and echovirus 7 seeded in mineral water was 103 to 104 PFU/spot. In cell cultures, positive signals were observed in the lysates of cells infected by one PFU. Higher positive signals were obtained with a short PV1 probe (nt 221-670) corresponding to the 5' noncoding region, which is a well preserved sequence among the enteroviruses, than with PV1 genomic probe. Hybridization allowed a good detection of enteroviral RNAs in wastewater specimens, but with a lower efficiency in surface water. In this case, amplification of viruses in the cell cultures gave significant hybridization results.

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