Serological characterization of Hungarian plum pox virus isolates

Three Hungarian (no. 2, 4 and 9), and a Moldavian (K) plum pox virus isolates were compared with a characterized Spanish isolate (5.15) by RT-PCR, ELISA, dot-blot and Western blot analysis. Monoclonal antibodies prepared against the external, intermediate and internal sequences of the coat protein of the Spanish isolate were able to differentiate the four isolates. Hungarian isolate No. 2 proved to be serologically identical to the Spanish isolate, while No. 4 showed appreciable differences and No. 9 could be recognized only by the monoclonal antibodies representing the intermedial and internal parts of the coat protein. K isolate showed a more distant relationship to other isolates. Our experiment provided the first demonstration of the presence of D type isolates in Hungary.