Evolution of diversity of fruits and vegetables crops
Résumé
Due to climatic conditions and cultural traditions, only a part of the world fruit and vegetable diversity is cultivated in Europe. Since the 1950s, major evolutions have affected most of the cultivated species at several levels: (i) an enlargement of the number of cultivated species, with the introduction for instance of kiwi (Actinidia), nashi (Pyrus pyrifolia) or Japanese plums (Prunus salicina); (ii) new cultigroups or botanical varieties have been introduced or created introducing market segmentation for instance red apricot, flat peach, parthenocarpic cucumber, or red Belgian endive; (iii) a tremendous increase of the number of available cultivars with almost 20000 cultivars of vegetables registered in the European catalogue. Nevertheless for most of the species, the number of cultivars has a tendency to increase in the most important cultigroups and to decrease in minor cultigroups (winter radish, running beans, peas, etc.). The diversity at the genotypic level can be estimated by neutral molecular markers like microsatellites or SNPs. Several situations have been described: (i) a good relationship between genotype and phenotype for instance in cherry tomatoes versus large-fruited types or in peach; (ii) a correlation between genotype and geographical origin; (iii) or a mix of both with foundation effects of a small number of parental accessions. New prospects or concerns based onto climatic change potential impacts and production durability have to be addressed. Development of future cultivars requires the mobilization of new adapted germplams. The characterization of the world existing resources on both morphological and genotypic bases is of major importance.