Development of a European common bean (Phaseolus vulgaris L.) core collection based on phaseoline electrophoretic patterns.

Archaeo-morphological, biochemical and molecular evidence suggest that common bean (Phaseolus vulgaris L) was separately domesticated in Andean and Mesoamerican centres (Gepts, 1988; Delgado-Salinas et al. 1988; Gepts and Debouck, 1991). Particularly, electrophoretic analysis of phaseoline, the major seed storage proteins, permitted to discriminate the two gene pools: Andean (“T” and “C” type) and Mesoamerican (“S” type) ones. At different times both gene pools Meso-american and Andean were introduced in Europe as confirmed by phaseoline patterns. The distribution of genetic diversity on the basis of Meso-american and Andean germoplasm in Europe is poorly known. In this study a collection of 544 European accessions of common bean (Phaseolus vulgaris L) from several genebanks (IPK, NGB, CUB, ANP, etc.) was analysed using SDS-PAGE phaseoline patterns (Romero et al., 1975). Over all, the 76.3 % of accessions is from Andean gene pool (45.59% phaseoline type “T” and 30.70% type “C”) and the remaining is from Mesoamerica (type “S”). As reported by other authors (Gepts, 1988) we found that phaseoline type “C” from Andean gene pool is the most frequent both in Italian and Iberian accessions. Type “T” is the most frequent Andean type among accessions from other origins. the Type “S” (from Mesoamerican gene pool) did show high frequencies (32.5%) in the germplasm from eastern-Europe and about 50% of type “S” from southeast Europe group are from Albania. These results, in agreement with the previous studies, show a different contribution of the two American gene pools to the colonization of Europe and the high adaptive ability of this species. On the basis of phaseoline type frequencies and country of origin a “core” collection of 300 accessions has been constituted representing the contribute of American gene pools to European germplasm.