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New Disease Reports (2018) 38, 9. http://dx.doi.org/10.5197/j.2044-0588.2018.038.009
First report of Peanut stunt virus on beans in Bulgaria
G. Pasev 1*, V. Radeva-Ivanova 1, Y. Manoussopoulos 2, M. Turina 3 and D. Kostova 4
1 Maritsa Vegetable Crops Research Institute, 32 Brezovsko Shosee Str. 4003 Plovdiv, Bulgaria; 2 ELGO-Demeter, Institute
of Industrial and Forage Crops, Plant Protection Division of Patras, NEO & Amerikis, Patras 26444, Greece; 3 Institute for
Sustainable Plant Protection, 73 Strada delle Cacce, I-10135 Turin, Italy; 4 Center of Plant Systems Biology and
Biotechnology, 139 Ruski Blvd, Plovdiv 4000, Bulgaria
*E-mail: gipasev@aol.com
Received: 25 May 2018. Published: 17 Aug 2018. Keywords: Cucumovirus, Phaseolus vulgaris
Figure 1 Figure 2 Figure 3
Figure 4
Common bean (Phaseolus vulgaris) is a traditional vegetable in Bulgaria.
The area grown in for 2013 was estimated to be 344 ha which increased
gradually to reach 708 ha in 2016. During the summer of 2013, leaf
samples (n=76) with virus-like symptoms were collected from bean plants
in fields around the Maritsa Vegetable Crops Research Institute and in
private gardens in regions near Plovdiv, Bulgaria. Disease incidence varied
from 10 to 50%. Symptoms consisted of green or yellow mosaic, blisters,
and leaf distortion (Fig. 1). In some locations the prevalent disease was
associated with severe stunting.
To identify the casual agent(s) of these symptoms DAS/TAS-ELISA tests
were performed using eleven antisera, specific to Alfalfa mosaic virus,
Bean common mosaic virus (BCMV), Bean common mosaic necrosis virus,
Bean yellow mosaic virus (BYMV), Broad bean wilt virus 1,Broad bean wilt
virus 2,Clover yellow vein virus (ClYVV), Cucumber mosaic virus (CMV),
Tobacco necrosis virus, Watermelon mosaic virus (Leibniz-Institute DSMZ,
Germany) and Peanut stunt virus (PSV) (Agdia, USA). Results revealed the
presence of common viruses, BCMV, CMV, BYMV and ClYVV, in the
majority of the samples. However, three samples were positive for PSV.
The PSV samples were traced to fields in which stunting symptoms were
prevalent.
Sap inoculation of the PSV-infected samples to Chenopodium
amaranticolor and Nicotiana benthamiana resulted in local chlorotic lesions
and leaf distortion, respectively. A single lesion isolate of each virus was
gradually propagated in tobacco plants (cv. White Burley) and used for
further characterisation. Mechanical inoculation of these isolates caused
systemic symptoms with large chlorotic lesions and rings in bean plants (cv.
Pinto) (Fig. 2) and local chlorotic and necrotic lesions in C. quinoa and C.
murale, respectively, followed by systemic chlorotic lesions in the upper
leaves in C. quinoa (Fig. 3). Electron microscopy of bean extracts revealed
isometric particles approximately 28 nm in diameter. RT-PCR of bean
extracts was performed using specific primers (PSV-CP-For, 5ˈ-
ATGGCATCTAGATCTGGTAA-3ˈ and PSV-CP-Rev 5ˈ-
GACCGGGAGCTTGGAAGCGGAA-3ˈ), that were designed using a
reference sequence from GenBank (Accession No. U31366.1). Amplicons
of the expected size (651 bp) were obtained from the coat protein region
for all three PSV CP isolates. Sequencing of these amplicons confirmed the
identification of PSV. These sequences were deposited in the NCBI
database (MG256178 - MG256180). Phylogenetic analysis (Fig. 4) of all
PSV isolates currently published in the NCBI database placed all three
Bulgarian isolates in the Western subgroup (II), typified by the American
PSV-W isolate (U31366).
PSV is known to cause severe infections on legumes worldwide. As a non-
persistently transmitted aphid-borne cucumovirus, it might spread to other
legumes including forage crops in Bulgaria. Monitoring infection of natural
hosts would provide additional information about the epidemiology of the
virus in Eastern Europe. To our knowledge this is the first report of PSV in
the country and the second report of the occurrence of the Western strain
of PSV in Europe (Diaz-Ruiz et al., 1979).
References
Diaz-Ruiz JR, Kaper JM, Waterworth HE, Devergne JC, 1979. Isolation
and characterization of peanut stunt virus from alfalfa in Spain.
Phytopathology 69, 504-509. http://dx.doi.org/10.1094/Phyto-69-504
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To cite this report: Pasev G, Radeva-Ivanova V, Manoussopoulos Y, Turina M, Kostova D, 2018. First report of Peanut stunt virus on beans
in Bulgaria. New Disease Reports 38, 9. http://dx.doi.org/10.5197/j.2044-0588.2018.038.009
©2018 The Authors This report was published on-line at www.ndrs.org.uk where high quality versions of the figures can be found.
New Disease Reports is a peer-reviewed on-line journal published by the British Society for Plant Pathology,
for more information visit http://www.ndrs.org.uk/ Page 9
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