Five VHSV isolates from different host species and Spanish geographical locations and three viral haemorrhagic septieaemia virus (VHSV) international reference serotypes (Fj, FT and 23-75) were studied by several characterized monoclonal antibodies (MAbs) including a neutralizing MAb to four structural proteins of VHSV. We report here the lack of reaction between anti-Ml and some of the isolates of VHSV and the homogeneity of most of the isolates with respect to the MAbs tested. The reagents obtained will improve diagnostic tests which currently use polyclonal antibodies.

Faba bean necrotic yellow virus (FBNYV) was not detected during 1994 to 1996 field surveys of faba beans (Vicia faba L.) in Spain (1). In 1997, however, one sample with symptoms of necrosis, collected in Baleares, was tested using ELISA (enzyme-linked immunosorbent assay) and was positive for both Tomato spotted wilt virus (TSWV) and FBNYV. FBNYV is a single-strand DNA virus that is transmitted by aphids and is the main virus disease of broad bean in North Africa and West Asia (2). During 1997 to 1999, faba bean plants with symptoms of necrosis, yellowing, small leaves, and stunting were collected from several fields in the Murcia Region (Spain) and were analyzed using ELISA. To detect FBNYV, we used monoclonal 2E9 supplied by H. J. Vetten (Institute of Plant Virology, Microbiology and Biosafety, BBA, Braunschweig, Germany). Of 700 samples analyzed, 34 were positive for FBNYV. Of the 34 positive samples, 12 tested positive, using commercial antiserum from Loewe, Inc. (Munich) for mixed infections with TSWV. FBNYV was transmitted to healthy faba bean plants by aphids (Acyrthosiphon pisum) in greenhouse experiments and was confirmed by ELISA. Preliminary epidemiological data showed a gradual increase in the number of plants infected with time in the same field. Aphid transmission of FBNYV to faba beans has established the disease in Spain and is a potential threat to other leguminous crops. This is the first report of a nanovirus in Europe. References: (1) J. Fresno et al. Plant Dis. 81:112, 1997. (2) L. Katul et al. Ann. Appl. Biol. 123:629, 1993.

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Broad bean (Vicia faba L.) plants showing symptoms suggestive of viral infection, such as stunting, leaf roll, mosaic, chlorosis, necrosis, and yellowing, were observed in the Andalucia, Baleares, Cataluna, and Murcia regions of Spain. A 4-year field survey showed the presence of five viruses: bean leaf roll luteovirus (BLRV), beet western yellows luteovirus (BWYV), bean yellow mosaic potyvirus (BYMV), tomato spotted wilt tospovirus (TSWV), and cucumber mosaic cucumovirus (CMV). Identity of viruses was first determined by enzyme-linked immunosorbent assay and confirmed by at least one other method, such as inoculation to plant hosts, electron microscopy, molecular hybridization, or immunocapture-reverse transcriptase-polymerase chain reaction. Of the 250 samples assayed, 93 were positive for BYMV, 21 for BLRV, 10 for BWYV, 30 for TSWV, and 2 for CMV. Faba bean necrotic yellow virus (a single-strand DNA virus) and broad bean mottle bromovirus, which are widely distributed in the Mediterranean basin, were not detected in the samples analyzed. BYMV was distributed in all regions, whereas TSWV was restricted only to Mediterranean areas. To our knowledge, this is the first report of viruses infecting broad bean in Spain.

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