Transmissibility of Field Isolates of Soybean Viruses by Aphis glycines

During the 2001 growing season, 191 symptomatic soybean (Glycine max (L.) Merr.) plants were dug from production plots in Indiana, Wisconsin, and Kentucky. Alfalfa mosaic virus (AMV), Bean pod mottle virus (BPMV), Bean yellow mosaic virus (BYMV), Peanut stunt virus (PSV), Tobacco ringspot virus (TRSV), and Soybean mosaic virus (SMV) were identified. No mixed infections were observed. The ability of the soybean aphid (Aphis glycines Matsamura) to transmit field isolates of these viruses was tested. Using naturally infected field- or greenhouse-grown soybean plants as sources, six isolates of SMV and two isolates of AMV were transmitted using a short feeding assay. One of two isolates of TRSV was transmitted by A. glycines in one of four experiments using an extended feeding transmission assay. BPMV was not transmitted by A. glycines in assays involving 11 field isolates and over 840 aphids. One field isolate each of BYMV and PSV were tested and no transmission by A. glycines was observed.

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Robust RNAi-Based Resistance to Mixed Infection of Three Viruses in Soybean Plants Expressing Separate Short Hairpins from a Single Transgene

Phytopathology ◽

10.1094/phyto-02-11-0056 ◽

2011 ◽

Vol 101 (11) ◽

pp. 1264-1269 ◽

Cited By ~ 33

Author(s):

Xiuchun Zhang ◽

Shirley Sato ◽

Xiaohong Ye ◽

Anne E. Dorrance ◽

T. Jack Morris ◽

...

Keyword(s):

Mosaic Virus ◽

Virus Resistance ◽

Soybean Mosaic Virus ◽

Alfalfa Mosaic Virus ◽

Cauliflower Mosaic Virus ◽

Systemic Resistance ◽

35S Promoter ◽

Virus Infections ◽

Bean Pod Mottle Virus ◽

Soybean Plants

Transgenic plants expressing double-stranded RNA (dsRNA) of virus origin have been previously shown to confer resistance to virus infections through the highly conserved RNA-targeting process termed RNA silencing or RNA interference (RNAi). In this study we applied this strategy to soybean plants and achieved robust resistance to multiple viruses with a single dsRNA-expressing transgene. Unlike previous reports that relied on the expression of one long inverted repeat (IR) combining sequences of several viruses, our improved strategy utilized a transgene designed to express several shorter IRs. Each of these short IRs contains highly conserved sequences of one virus, forming dsRNA of less than 150 bp. These short dsRNA stems were interspersed with single-stranded sequences to prevent homologous recombination during the transgene assembly process. Three such short IRs with sequences of unrelated soybean-infecting viruses (Alfalfa mosaic virus, Bean pod mottle virus, and Soybean mosaic virus) were assembled into a single transgene under control of the 35S promoter and terminator of Cauliflower mosaic virus. Three independent transgenic lines were obtained and all of them exhibited strong systemic resistance to the simultaneous infection of the three viruses. These results demonstrate the effectiveness of this very straight forward strategy for engineering RNAi-based virus resistance in a major crop plant. More importantly, our strategy of construct assembly makes it easy to incorporate additional short IRs in the transgene, thus expanding the spectrum of virus resistance. Finally, this strategy could be easily adapted to control virus problems of other crop plants.

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Occurrence of Seed Coat Mottling in Soybean Plants Inoculated with Bean pod mottle virus and Soybean mosaic virus

Plant Disease ◽

10.1094/pdis.2003.87.11.1333 ◽

2003 ◽

Vol 87 (11) ◽

pp. 1333-1336 ◽

Cited By ~ 34

Author(s):

H. A. Hobbs ◽

G. L. Hartman ◽

Y. Wang ◽

C. B. Hill ◽

R. L. Bernard ◽

...

Keyword(s):

Virus Infection ◽

Mosaic Virus ◽

Resistance Gene ◽

Seed Coat ◽

Soybean Mosaic Virus ◽

Soybean Seed ◽

Mottle Virus ◽

Bean Pod Mottle Virus ◽

Soybean Plants ◽

Soybean Seed Coat

Soybean seed coat mottling often has been a problematic symptom for soybean growers and the soybean industry. The percentages of seed in eight soybean lines with seed coat mottling were evaluated at harvest after inoculating plants during the growing season with Bean pod mottle virus (BPMV), Soybean mosaic virus (SMV), and both viruses inside an insect-proof cage in the field. Results from experiments conducted over 2 years indicated that plants infected with BPMV and SMV, alone or in combination, produced seed coat mottling, whereas noninoculated plants produced little or no mottled seed. BPMV and SMV inoculated on the same plants did not always result in higher percentages of mottled seed compared with BPMV or SMV alone. There was significant virus, line, and virus-line interaction for seed coat mottling. The non-seed-coat-mottling gene (Im) in Williams isoline L77-5632 provided limited, if any, protection against mottling caused by SMV and none against BPMV. The Peanut mottle virus resistance gene Rpv1 in Williams isoline L85-2308 did not give any protection against mottling caused by SMV, whereas the SMV resistance gene Rsv1 in Williams isoline L78-379 and the resistance gene or genes in the small-seeded line L97-946 gave high levels of protection against mottling caused by SMV. The correlations (r = 0.77 for year 2000 and r = 0.89 for year 2001) between virus infection of the parent plant and seed coat mottling were significant (P = 0.01), indicating that virus infection of plants caused seed coat mottling.

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Incidence of Alfalfa mosaic virus, Bean pod mottle virus, and Soybean mosaic virus in Nebraska Soybean Fields

Plant Health Progress ◽

10.1094/php-2006-0424-01-hm ◽

2006 ◽

Vol 7 (1) ◽

pp. 37 ◽

Cited By ~ 2

Author(s):

Loren J. Giesler ◽

Amy D. Ziems

Keyword(s):

Mosaic Virus ◽

Soybean Mosaic Virus ◽

Alfalfa Mosaic Virus ◽

The United States ◽

Planting Date ◽

Mottle Virus ◽

North Central Region ◽

Bean Pod Mottle Virus ◽

North Central ◽

The North

The incidence of soybean viruses is increasing across the North Central Region of the United States as indicated by survey efforts and grower reports from several states. To determine the level of virus infection in Nebraska, we surveyed soybean fields for two consecutive years. Alfalfa mosaic virus (AMV) was detected in 52% of the fields in 2001 and in 56% of fields in 2002. The incidence of Bean pod mottle virus (BPMV) varied more, with 54% of fields testing positive in 2001 and 91% testing positive in 2002. Soybean mosaic virus (SMV) was not detected in 2001, but it was detected in 31% of fields in 2002. The widespread distribution of detected SMV in 2002 is suggestive of introduction with seed. The incidence of BPMV was significantly higher in fields planted earlier than the recommended optimum planting date in one of the two years studied. The widespread incidence of AMV and BPMV and the irregular occurrence of SMV indicate that further studies of soybean viral diseases in Nebraska are warranted. Accepted for publication 13 March 2006. Published 24 April 2006.

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Assessment of Common Soybean-Infecting Viruses in Ohio, USA, Through Multi-site Sampling and High-Throughput Sequencing

Plant Health Progress ◽

10.1094/php-rs-16-0018 ◽

2016 ◽

Vol 17 (2) ◽

pp. 133-140 ◽

Cited By ~ 1

Author(s):

Junping Han ◽

Leslie L. Domier ◽

Bryan J. Cassone ◽

Anne Dorrance ◽

Feng Qu

Keyword(s):

Mosaic Virus ◽

High Throughput ◽

High Throughput Sequencing ◽

Virus Disease ◽

Soybean Mosaic Virus ◽

Alfalfa Mosaic Virus ◽

Plant Viruses ◽

Yellow Mosaic Virus ◽

Tobacco Streak Virus ◽

Streak Virus

Multi-site sampling was conducted during 2011 and 2012 to assess the scope of virus disease problems of soybean in Ohio, USA. A total of 259 samples were collected from 80 soybean fields distributed in 42 Ohio counties, accounting for more than 90% of major soybean-growing counties in Ohio. A high-throughput RNA-Seq approach was adopted to identify all viruses in the samples that share sufficient sequence similarities with known plant viruses. To minimize sequencing costs, total RNA extracted from up to 20 samples were first pooled to make up regional pools, resulting in eight regional pools per year in both 2011 and 2012. These regional pools were further pooled into two yearly master pools of RNA, and sequenced using the Illumina's HiSeq2000 platform. Bioinformatic analyses of sequence reads led to the identification of signature sequences of nine different viruses. The originating locations of these viruses were then mapped with PCR or RT-PCR. This study confirmed the widespread distribution of Bean pod mottle virus, Soybean vein necrosis virus, Tobacco ringspot virus, and Tobacco streak virus in Ohio. It additionally revealed occasional association of Alfalfa mosaic virus, Bean yellow mosaic virus, Clover yellow vein virus, Soybean mosaic virus, and Soybean Putnam virus with Ohio soybean. This is the first statewide survey of soybean viruses in Ohio, and provides the much-needed baseline information for management of virus diseases of soybean. Accepted for publication 20 May 2016. Published 10 June 2016.

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First Report of Transmission of Soybean mosaic virus and Alfalfa mosaic virus by Aphis glycines in the New World

Plant Disease ◽

10.1094/pdis.2001.85.5.561c ◽

2001 ◽

Vol 85 (5) ◽

pp. 561-561 ◽

Cited By ~ 88

Author(s):

J. H. Hill ◽

R. Alleman ◽

D. B. Hogg ◽

C. R. Grau

Keyword(s):

Mosaic Virus ◽

Central Region ◽

Soybean Mosaic Virus ◽

Field Isolate ◽

Alfalfa Mosaic Virus ◽

Aphid Species ◽

North Central Region ◽

North Central ◽

The North ◽

Efficient Vector

The recent discovery of the soybean aphid, Aphis glycines Matsamura, in the North Central region of the United States is significant because it is the first time that a soybean-colonizing aphid has been detected in the New World. Although the aphid has the potential to cause physiological loss of up to 52% on soybeans (4), it can also transmit Soybean mosaic virus (SMV). Transmission of Alfalfa mosaic virus (AMV) has not been reported. SMV, and less commonly AMV, are found in soybeans in the North Central states and are transmitted by numerous aphids in a nonpersistent manner (2; Grau, unpublished). For SMV, potential exists for specificity of transmission between virus strain and aphid species (3). For these reasons, it was important to determine if an endemic isolate of these viruses could be transmitted by this introduced species of aphid in the North Central region. Transmission experiments were conducted as described (3), using 3, 5, and 10 aphids per plant. Ten plants of the soybean cultivar Williams 82 were used for each treatment. To preclude confounding results by possible seed transmission, plants used in all tests were grown from seeds harvested from virus-indexed plants grown in the greenhouse. For experiments involving SMV, the aphid-transmissible field isolate Al5 (GeneBank Accession no. AF242844) and, as a negative control, the non-aphid transmissible isolate N (GeneBank Accession no. D500507) were used. For experiments involving AMV, a field isolate of AMV, confirmed by ELISA and host range, was used. The aphid species Myzus persicae was maintained on broad bean and A. glycines was maintained on virus-free soybean. The protocol for transmission studies of AMV was identical to that used in the SMV study, except only A. glycines was tested. For experiments, plants were periodically observed for symptom development and tested by ELISA 4 to 5 weeks after inoculation access. No transmission of SMV-N occurred in any tests, which together involved 180 aphids each of M. persicae or A. glycines. For the Al5 isolate, transmission efficiencies of 30, 50, and 50% were obtained with 3, 5, and 10 individuals, respectively, of M. persicae per plant. Efficiencies for A. glycines were 30, 40, and 40%. Transmission levels by the two aphid species did not differ significantly (t-test, P = 0.01). For AMV, corresponding transmission efficiencies were 0, 0, and 20%. The data suggest that the introduced A. glycines can be an efficient vector of SMV, but a less efficient vector of AMV, in the North Central region. Transmission of AMV by M. persicae has been documented (1) but was not examined in this study. Transmission of SMV and AMV by A. glycines is of concern because it may increase SMV and AMV incidence. With the recent outbreak of Bean pod mottle virus (BPMV) in the region, the potential for synergism of SMV and BPMV is increased (2). References: (1) M. B. Castillo and G. G. Orlob. Phytopathology 56:1028, 1966. (2) G. L. Hartman et al., eds. 1999. Compendium of Soybean Diseases, 4th Ed. American Phytopathological Society, St. Paul, MN. (3) B. S. Lucas and J. H. Hill. Phytopathol. Z. 99:47, 1980. (4) C. L. Wang et al. Plant Prot. 20:12, 1994.

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Occurrence and Relative Incidence of Viruses Infecting Soybeans in Iran

Plant Disease ◽

10.1094/pdis.2004.88.10.1069 ◽

2004 ◽

Vol 88 (10) ◽

pp. 1069-1074 ◽

Cited By ~ 28

Author(s):

A. R. Golnaraghi ◽

N. Shahraeen ◽

R. Pourrahim ◽

Sh. Farzadfar ◽

A. Ghasemi

Keyword(s):

Mosaic Virus ◽

Soybean Mosaic Virus ◽

Alfalfa Mosaic Virus ◽

Soybean Seed ◽

Ringspot Virus ◽

Yellow Mosaic Virus ◽

Tobacco Streak Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Streak Virus ◽

Natural Occurrence

A survey was conducted to determine the incidence of Alfalfa mosaic virus (AlMV), Bean common mosaic virus (BCMV), Bean yellow mosaic virus (BYMV), Blackeye cowpea mosaic virus (BlCMV), Cucumber mosaic virus (CMV), Pea enation mosaic virus (PEMV), Peanut mottle virus (PeMoV), Soybean mosaic virus (SMV), Tobacco mosaic virus (TMV), Tobacco ringspot virus (TRSV), Tobacco streak virus (TSV), Tomato ringspot virus (ToRSV), and Tomato spotted wilt virus (TSWV) on soybean (Glycine max) in Iran. Totals of 3,110 random and 1,225 symptomatic leaf samples were collected during the summers of 1999 and 2000 in five provinces of Iran, where commercial soybean is grown, and tested by enzyme-linked immunosorbent assay (ELISA) using specific polyclonal antibodies. Serological diagnoses were confirmed by electron microscopy and host range studies. The highest virus incidence among the surveyed provinces was recorded in Mazandaran (18.6%), followed by Golestan (15.7%), Khuzestan (14.2%), Ardabil (13.9%), and Lorestan (13.5%). Incidence of viruses in decreasing order was SMV (13.3%), TSWV (5.4%), TRSV (4.2%), TSV (4.1%), PEMV (2.9%), BYMV (2.2%), ToRSV (2.1%), AlMV (1.3%), BCMV (0.8%), and CMV (0.6%). Additionally, 1.5% of collected leaf samples had positive reactions in ELISA with antiserum to TMV, indicating the possible infection of soybeans in Iran with a Tobamovirus that is related serologically to TMV. Of 195 leaves from plants showing soybean pod set failure syndrome (PSF) in Mazandaran and Lorestan, only 14 (7.2%) samples had viral infection. No correlation was observed between PSF and presence of the 13 viruses tested, suggesting the involvement of other viruses or factors in this syndrome. To investigate the presence of seed-borne viruses, including SMV, TRSV, ToRSV, and TSV, 7,830 soybean seeds were collected randomly at harvesting time from the major sites of soybean seed production located in Mazandaran and Golestan provinces. According to ELISA analyses of germinated seedlings, 7.1 and 8.9% of the seed samples from Golestan and Mazandaran provinces, respectively, transmitted either SMV, TRSV, ToRSV, or TSV through seed. We also showed that SMV and other seed transmissible viruses, as well as TSWV, usually are the most prevalent viruses in soybean fields in Iran. In this survey, natural occurrence of AlMV, BCMV, BlCMV, BYMV, CMV, PEMV, PeMoV, and TSWV was reported for the first time on soybeans in Iran.

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Soybean Cytochrome b5 Is a Restriction Factor for Soybean Mosaic Virus

Viruses ◽

10.3390/v11060546 ◽

2019 ◽

Vol 11 (6) ◽

pp. 546 ◽

Cited By ~ 1

Author(s):

Hexiang Luan ◽

Haopeng Niu ◽

Jinyan Luo ◽

Haijian Zhi

Keyword(s):

Mosaic Virus ◽

Soybean Mosaic Virus ◽

Cytochrome B5 ◽

Polymerase Chain Reaction Analysis ◽

Bimolecular Fluorescence Complementation ◽

Cell Periphery ◽

Bean Pod Mottle Virus ◽

Protein Targets ◽

Bimolecular Fluorescence Complementation Assay ◽

Soybean Plants

Soybean mosaic virus (SMV) is one of the most destructive viral diseases in soybeans (Glycine max). In this study, an interaction between the SMV P3 protein and cytochrome b5 was detected by yeast two-hybrid assay, and bimolecular fluorescence complementation assay showed that the interaction took place at the cell periphery. Further, the interaction was confirmed by co-immunoprecipitation analysis. Quantitative real-time polymerase chain reaction analysis revealed that GmCYB5 gene was differentially expressed in resistant and susceptible soybean plants after inoculation with SMV-SC15 strain. To test the involvement of this gene in SMV resistance, the GmCYB5 was silenced using a bean pod mottle virus (BPMV)-based vector construct. Results showed that GmCYB5-1 was 83% and 99% downregulated in susceptible (NN1138-2) and resistant (RN-9) cultivars, respectively, compared to the empty vector-treated plants. Silencing of GmCYB5 gene promotes SMV replication in soybean plants. Our results suggest that during SMV infection, the host CYB5 protein targets P3 protein to inhibit its proliferation. Taken together, these results suggest that CYB5 is an important factor in SMV infection and replication in soybeans, which could help soybean breeders develop SMV resistant soybean cultivars.

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First Report of Bean pod mottle virus in Soybean in Ohio

Plant Disease ◽

10.1094/pdis.2001.85.9.1029a ◽

2001 ◽

Vol 85 (9) ◽

pp. 1029-1029 ◽

Cited By ~ 6

Author(s):

A. E. Dorrance ◽

D. T. Gordon ◽

A. F. Schmitthenner ◽

C. R. Grau

Keyword(s):

Host Range ◽

Mosaic Virus ◽

Soybean Mosaic Virus ◽

Mottle Virus ◽

Yellow Mosaic Virus ◽

Economic Losses ◽

Enzyme Linked Immunosorbent Assay ◽

Bean Pod Mottle Virus ◽

First Report ◽

Soybean Leaf

Soybean has been increasing in importance and acreage over wheat and corn for the past decade in Ohio and is now planted on 4.5 million acres. Previous surveys in Ohio of viruses infecting soybean failed to identify Bean pod mottle virus (BPMV) and soybean virus diseases have rarely caused economic losses (1). During 1999, producers in Ohio noticed virus-like symptoms in soybeans in a few isolated locations. Soybeans with green stems, undersized and “turned up pods” were collected from Union, Wood and Wyandot Counties during October 1999 and soybeans with crinkled, mottled leaves were collected in Henry, Licking and Sandusky during August 2000. Five to six plants were collected from a single field from each county each year. In 1999, samples were sent to the University of Wisconsin-Madison, where one symptomatic leaflet/sample was ground in 3 ml of chilled phosphate buffered saline (pH 7.2). Leaf sap was placed in 1.5-ml centrifuge tubes and stored at 4°C for 24 h. Sap was assayed for the presence of BPMV using an alkaline phosphatase-labeled double-antibody sandwich enzyme-linked immunosorbent assay (DAS ELISA) for BPMV (AgDia Inc., Elkhart, IN). All samples tested were positive for BPMV. Samples collected in 1999 were also maintained at The Ohio State University in Harosoy soybean and in 2000 assayed serologically along with samples collected in 2000 for BPMV and Soybean mosaic virus (SMV) by ELISA and for Tobacco ringspot virus (TRSV) and Bean yellow mosaic virus (BYMV) by a host-range symptom assay; SMV, BYMV and TRSV had been identified from soybean in previous Ohio surveys. Soybean leaf samples were assayed using F(ab′)2-Protein A ELISA with antiserum prepared in 1968 to a southern U.S. isolate of BPMV and to an Ohio isolate of Soybean mosaic virus (SMV) prepared in 1967, both stored at −20°C. Diseased and non-symptomatic soybean leaf samples were ground in 4 ml 0.025M Tris pH 8.0, 0.015M NaCl and 0.05% Tween 20. Extracts were tested for BPMV and SMV by ELISA following a protocol described elsewhere (2). All of the samples collected during 1999 and maintained in the greenhouse tested positive for both BPMV and SMV while all of those samples collected during 2000 tested positive for BPMV and negative for SMV. Host-range symptom assays were conducted with leaf extracts prepared by grinding 1 g tissue:10 ml potassium phosphate buffer, pH 7.0. Extracts were inoculated by leaf rub method to Harosoy soybean, Phaseolus vulgaris cvs. Red Kidney and Bountiful, cowpea, and cucumber. The host-range symptom assays of both the 1999 and 2000 samples were negative for TRSV and BYMV; cowpea failed to express local lesions and cucumber systemic mosaic characteristic of TRSV infection and the two Phaseolus cultivars the yellow mosaic characteristic of BYMV infection. These results indicate that both BPMV and SMV were present in the samples in 1999 but only BPMV in 2000. The distribution of BPMV within Ohio and economic impact of this virus have yet to be determined. This is the first report of BPMV in Ohio. References: (1) A. F. Schmitthenner and D. T. Gordon. Phytopathology 59:1048, 1969. (2) R. Louie et al. Plant Dis. 84:1133–1139, 2000.

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Weeds as Reservoirs of Viruses in Agrobiocenoses of Legumes in Ukraine

Mikrobiolohichnyi Zhurnal ◽

10.15407/microbiolj82.06.094 ◽

2020 ◽

Vol 82 (6) ◽

pp. 94-106

Author(s):

A.N. Kyrychenko ◽

◽

M.M. Bohdan ◽

I.S. Shcherbatenko ◽

◽

...

Keyword(s):

Mosaic Virus ◽

Soybean Mosaic Virus ◽

Alfalfa Mosaic Virus ◽

Virus Transmission ◽

Bean Common Mosaic Virus ◽

Plant Viruses ◽

Primary Sources ◽

Yellow Mosaic Virus ◽

Tomato Ringspot Virus ◽

Cultivated Plant

This paper is the review of literature data on the prevalence of weeds as possible reservoirs of plant viruses in agroecosystems of Ukraine. The information presented here about the most distributed weeds as reservoirs of harmful plant viruses will be useful for understanding the pathogens ecology, analyzing the virus epidemiology and for disease management. Since legumes are the main crops grown in Ukraine, the paper focuses on weeds spreading in the agrosystems of cultivated plant. The paper provides information about the primary sources of soybean viruses (Soybean mosaic virus, Cucumber mosaic virus, Alfalfa mosaic virus, Tomato ringspot virus) and bean viruses (Bean yellow mosaic virus, Bean common mosaic virus) as well as the main factors contributing the virus transmission in agrocenosis.

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Aphis glycines as a Vector of Persistently and Nonpersistently Transmitted Viruses and Potential Risks for Soybean and Other Crops

Plant Disease ◽

10.1094/pd-90-0920 ◽

2006 ◽

Vol 90 (7) ◽

pp. 920-926 ◽

Cited By ~ 34

Author(s):

R. Y. Wang ◽

A. Kritzman ◽

D. E. Hershman ◽

S. A. Ghabrial

Keyword(s):

Mosaic Virus ◽

Soybean Mosaic Virus ◽

The United States ◽

Plant Viruses ◽

Soybean Aphid ◽

Aphis Glycines ◽

Yellow Mosaic Virus ◽

Coding Region ◽

Rt Pcr ◽

First Report

The recently introduced soybean aphid (Aphis glycines), which is widespread in the soybean-growing regions in the United States, is the only aphid able to develop large colonies on soybean. Although its potential as a vector of plant viruses is recognized, reports on virus transmission efficiency by this aphid species are limited. In the present study, we examined the ability of A. glycines to transmit several economically important viruses. The results showed that A. glycines transmitted the potyviruses Bean yellow mosaic virus (BYMV) and Soybean mosaic virus from soybean to soybean more efficiently than Myzus persicae. However, M. persicae transmitted the alfamovirus Alfalfa mosaic virus and the potyviruses Tobacco etch virus (TEV) and Tobacco vein mottling virus (TVMV) from tobacco to tobacco more efficiently than A. glycines. This is the first report to demonstrate that the soybean aphid can vector TEV and TVMV, two economically important tobacco viruses. This also is the first report to document successful transmission of BYMV by A. glycines. All attempts to transmit the nepovirus Tobacco ringspot virus by A. glycines were unsuccessful, regardless of the length of the acquisition and inoculation feeding periods. Although the luteovirus Soybean dwarf virus (SbDV) was widely distributed in red and white clover in Kentucky, it was not detected in soybean. All transmission experiments of SbDV by A. glycines were unsuccessful. A reverse-transcription polymerase chain reaction (RT-PCR) assay was developed to detect SbDV in single aphids using a pair of primers designed to amplify a 372-bp PCR fragment in the coding region of SbDV coat protein. Although A. glycines was not a vector of SbDV, the virus was detected in 100% of tested aphids by RT-PCR after a 24- to 48-h virus acquisition access feeding. The practical applications of RT-PCR in detecting persistently transmitted viruses are discussed.

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