Construction of a living library of Solanum tomentosum introgression lines into the S. melongena genome: A tool to exploit novel genetic diversity for eggplant breeding

Plant architecture, fruit shape and colour, as well as functional properties and resistance to biotic and abiotic stresses are among the main target traits in eggplant genetic improvement. Solanum tomentosum L. is a wild relative of eggplant which is a valuable source of key agronomical traits, including plant architecture, fruit biochemical composition and resistances to pathogens. Following six back–cross cycles using the cultivated eggplant background line ‘67/3’ as recurrent parent, we developed a population of 148 Advanced Backcrossed Lines (ABLs) and Introgression Lines (ILs), each harbouring chromosomal segments from the wild species. Collectively, these introgressed segments cover more than 95 % of the S. tomentosum genome. The resulting ILs population was used to localize chromosomal regions involved in the control of traits of agronomical interest such as plant height, fruit peel pigmentation, and resistance to fungal diseases.