Increasing the Genetic Base of Modern Cultivars of Eggplant of the Semi-Long Black Type

Abstract

The eggplant (Solanum melongena) semi-long black varietal type is the most important in most European markets. Although open pollinated, pure lines and F1 hybrid cultivars exist within this varietal group, the latter predominate in the commercial production of eggplants, especially under greenhouse conditions. However, molecular markers studies have found that modern F1 hybrids present a reduced genetic base. This work is aimed at using a wide diversity of black eggplants for developing pure lines for obtaining hybrids heterotic for yield and increasing the genetic base of the black eggplants genepool. Thirty hybrid and non-hybrids varieties of black eggplants were used. Materials were characterized for morphological and agronomic traits of interest under greenhouse conditions. Molecular characterization was also performed using 16 SSR markers. A pedigree breeding programme was performed based on morphoagronomic traits until the F8 or F9 generations. Molecular analysis revealed that original materials could be separated in three main clusters groups, one made up by varieties from large companies that include the most successful varieties and the two other by an admixture of materials including non-hybrid varieties and F1 hybrids with moderate or low economic importance. The pedigree selection made allowed the final selection of 15 lines, which according to its origin, should have an increased genetic diversity compared to modern F1 hybrids. These lines, which present a very good performance under greenhouse conditions have been crossed in order to obtain hybrids heterotic for yield. These selected lines will be used to obtain a new generation of eggplant F1 hybrids with increased genetic base.