First report of Broad bean wilt virus 1 in Slovenia

Abstract

) cvs Atol,Olimpus, Bjanca and Verbrana, showing virus-like symptoms, were observedin a commercial field in SE Slovenia. Discolorations, rings or dark bumpson fruits resulted in almost a 100% loss of the yield in some areas. Symptomson leaves were expressed as arabesques or concentric rings. In autumn,infected plants expressed less severe symptoms and produced symptomless fruits.Infected leaves and fruits, with various symptoms, were tested by ELISAfor the presence of BBWV 1 (Broad bean wilt virus 1), BBWV 2 (Broadbean wilt virus 2), CSNV (Chrysanthemum stem necrosis virus), CMV(Cucumber mosaic virus ), INSV ( Impatiens necrotic spot virus ) and TSWV(Tomato spotted wilt virus ). Positive results were obtained only for BBWV1 in all samples collected from the epidemic area. Immuno-serological elec-tron microscopy (ISEM) (antibodies from DSMZ, Germany) of crude sapextracts confirmed BBWV 1 infection. RT-PCR using BBWV 1 specificprimers B1/B2 (Rubio et al., 2002) produced an amplicon of approxi-mately the expected size (500 bp) from extracts from infected but nothealthy plants. The sequence of the amplicon was determined (GenBankAccession No. EF405826). BLAST analysis of a 334 bp segment, encom-passing part of the two coat proteins genes, showed approximately 80%nt identity with various BBWV 1 isolates. Amino acid identities rangedfrom 90 to 92% with BBWV 1 isolates and from 54 to 58% with BBWV2 isolates. Sap of plants with symptoms was used for mechanical inocula-tion of test plants. Local and systemic symptoms were observed on pepper,Chenopodium quinoa, Nicotiana rustica, and N. tabacum cv. WhiteBurley. No symptoms were observed on N. clevelandii, N.benthamianaand Lycopersicon esculentum . BBWV 1 was also identified in one out of sixweed species belonging to the family Cichoriaceae, expressing mild mosaicsymptoms and growing near the epidemic area. This is the first report ofBBWV 1 in Slovenia.AcknowledgementsWe thank the Slovenian PARS, D.-E.Lesemann (BBA, Germany), J.Th.J.Verhoeven (PPS, Netherlands), B. Frajman (UL, Slovenia) and N. Petrovi c (NIB, Slovenia) for their help.