Genetic Diversity of Bulgarian Phaseolus vulgaris L. Germplasm Collection

The common bean, Phaseolus vulgaris (L.) Savi, is a member of the genus Phaseolus, belonging to subtribe Phaseolinae. It in turn is a member of the tribe Phaseoleae of the subfamily Papilionoideae and the family Leguminosae (Fabaceae) (van Eseltine, 1931; in Lackey, 1977; Maréchal et al., 1978). The neotropical genus Phaseolus includes about 50 to 60 species of wild bean (Toro et al., 1990), most of them distributed in Mesoamerica, five of which are cultivated: P. vulgaris (L.) Savi (common), P. dumosus Macfady (tepari), P. coccineus L. (multicolored, scarlet-coloured), P. lunatus L. (Lima) and P. polyanthus Green (Debouck, 1989; Caicedo et al., 1999; Delgado-Salinas et al., 1999; Gutiérrez Salgado et al., 1995). The last four species have much narrower commercial importance than P. vulgaris. In the USA less than five economically important varieties of common bean occupy half the area of this culture and at the same time it is from there that more than 10% of world production originates (Pachico, 1989). The vast narrowing of genetic variability is an indication of the risk of potential loss of a species and emphasizes the importance of its evaluation.