Identification of filamentous virus which infected red clover (\kur{Trifolium pratense})

Samples of red clover plants characteristic with dwarf growth were investigated with transmission electron microscopy. Most frequent virus particles observed there were filamentous ones of 300 to 800 nm long. Nucleic acid was isolated, transcribed and amplified using PCR with potexvirus- and potyvirus-specific primers 353G1, 353G2 (Petrzik, K., unpublished data), P9502, P0502 (Revers et al., 1999) and Poty2/P4 (Gibbs and Mackenzie, 1997). Successful amplification with potexvirus-specific primers, sequencing and comparison with GenBank sequences revealed White clover mosaic virus (WClMV) there. Coat protein gene of this virus was obtained with amplification and compared with complete sequence of WClMV from GenBank. O-strain of WClMV was identified