International Centre for Tropical Agriculture (CIAT), AA 6713 Cali, Colombia.
Abstracts of the papers presented at the 16th Annual Convention and International Symposium of Indian Virological Society on “Management of Vector-Borne Viruses” at International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru-502324, Hyderabad, India, February 7–10, 2006.
Bean common mosaic is one of the oldest viral diseases of plants, having been reported from Russia in the 1890s. It is not known whether the ‘Type’ strain of Bean common mosaic virus (BCMV) originated in the centre of origin of Phaseolus vulgaris, but it is certainly the predominant BCMV strain in Latin America. However, the greatest pathogenic diversity of BCMV is found outside this region, mainly in the United States and Europe. With the advent of molecular techniques to characterize plant viruses, BCMV was shown to consist of two phylogenetically distinct groups of virus strains. In 1997, a second virus species, Bean common mosaic necrosis virus (BCMNV), was recognized by the Potyviridae Study Group. BCMNV includes strains NL3, NL5 and NL8. These three BCMNV strains induce systemic necrosis in common bean genotypes that possess monogenic dominant resistance to BCMV and BCMNV, and they are not dependent on ambient temperature. The relatively high incidence of BCMNV NL3 in east and central Africa lead some scientists to propose an African origin for these strains. However, NL5 has not been detected in Africa, whereas the three BCMNV strains are present in Europe. Other legume viruses currently re-classified as BCMV strains are: Azuki mosaic, Blackeye cowpea mosaic and Peanut stripe viruses. The genetic interaction between P. vulgaris and BCM/BCMN viruses is well known and used to develop bean cultivars possessing multiple resistance genes against these viruses.
