Exploracao da diversidade genetica das passifloras

On the basis of literature and field information on the utilization of passion fruits, 81 species giving an edible fruit were inventoried in the genus Passiflora. This figure is much higher than previous estimates of 50 to 60 species. Those 81 species are mostly concentrated in subgenera Passiflora (43), Tacsonia and Manicata (17), Decaloba (13), and Distephana (5), while subgenera Dysosmia, Dysosmioides and Tacsonioides include one species each. Within subgenus Passiflora, the most promising series are Incarnatae (5), including the two forms of P. edulis and P. incarnata; Tiliifoliae, with nine species organized around sweet granadillas, six of them very similar to P. ligularis, or the hard-shelled granadilla (P. maliformis); Quadrangulares (3), with sweet maracuja (P. alata) and the giant granadilla (P. quadrangularis) that form a same gene pool possibly including P. trialata; Laurifoliae, with 14 superior and very similar fruit species, needing evaluation; Lobatae, with six species that can contribute resistance genes to the main economic species, be used as rootstock, or be developed into double purpose species (fruit and ornamental) for the garden. Subgenus Tacsonia offers good perspectives to improve and diversify the currently commercialized banana passion fruits, using germplasm from eight closely related species and botanical varieties. In addition, the cultivation of the rosy passion fruit and the Antioquia banana passion fruit could be maintained and improved, enriching the genetic basis of these crops with five and three closely related species respectively. Cultivation of the mountain granadilla (P. pinnatistipula) could benefit from breeding for smaller seeds and higher pulp content. At least five red-flowered fruit species mentioned for subgenus Distephana could be bred into double purpose plants for the tropical garden. The 13 species from subgenus Decaloba and 5 species from series Serratifoliae, Simplicifoliae e Setaceae of subgenus Passiflora present no interest for the development of commercial fruit crops. (Résumé d'auteur)