BIOLOGICAL AND MOLECULAR CHARACTERISTICS OF BEAN COMMON MOSAIC VIRUS ISOLATES CIRCULATING IN COMMON BEAN IN IRAN
T. Johary, A. Dizadji, M. Naderpour
Bean common mosaic virus (BCMV) is one of the most widespread and economically important seed and aphid-transmitted viruses. During 2010-2011, a total of 2410 symptomatic bean (Phaseolus vulgaris) leaf samples were collected from nine provinces of Iran and checked by DAS-ELISA (double antibody sandwich enzyme-linked immunsorbent assay), resulting in detection of BCMV in 655 samples. Following biological purification, the reaction of 16 differential bean cultivars (belonging to 11 host groups) against five geographical BCMV isolates revealed the occurrence of five different BCMV pathogroups, PG- I, II, IV, V and VII, which were new for Iran. The response of five commonly cultivated bean genotypes against three BCMV pathotypes (I, II and IV) was evaluated by semi-quantitave ELISA and two genotypes, Chiti karaj and Jules, were characterized as highly sensitive and tolerant genotypes, respectively. Pathogenicity of three different BCMV pathotypes on five bean genotypes used in this study revealed that they all belong to host group-1. Amplification of the 3'-terminal region (comprising coat protein region and partial 3'-UTR) of four BCMV isolates was performed by reverse transcription polymerase chain reaction (RT-PCR). Phylogenetic analysis of nucleotide and deduced amino acid sequences of coat protein genes did not differentiate BCMV isolates by host, location and pathogenicity group.