a1 Dipartimento di Scienze Agronomiche e Genetica Vegetale Agraria, Università degli Studi di Sassari, Sassari, Italy
a2 Dipartimento di Scienze Ambientali e delle Produzioni Vegetali, Università Politecnica delle Marche, Ancona, Italy
a3 CRA-CER Council for Agricultural Research – Cereal Research Centre, S.S. 16, Km 675, 71122 Foggia, Italy
a4 Centro per la Conservazione e Valorizzazione della Biodiversità Vegetale, Università degli Studi di Sassari, Surigheddu, Alghero, Italy
Here, we present a brief overview of the main studies conducted on the common bean (Phaseolus vulgaris L.) in Europe and other countries outside its centres of origin. We focus on the proportions of the Andean and Mesoamerican gene pools, and on the inter-gene pool hybridization events. In Europe, for chloroplast microsatellites, 67% of European germplasm is of Andean origin. Within Europe, interesting trends have been seen; indeed, the majority of the Andean type is found in the three macro-areas of the Iberian Peninsula, Italy and central-northern Europe, while, in eastern and south-eastern Europe, the proportion of the Mesoamerican type increased. On a local scale, the contribution of the Mesoamerican type is always low. On other continents, various situations are seen using different markers: in China and Brazil, the Mesoamerican gene pool prevails, while in an African sample, overall, both gene pools are equally represented, with differences in individual countries. The frequency of European bean genotypes deriving from at least one hybridization event was 44% with an uneven distribution. Interestingly, hybrids tend to have intermediate seed size in comparison with ‘pure’ Andean or Mesoamerican types. On other continents, very few hybrids are found, probably because of the different marker systems used.
(Online publication March 15 2011)