Genomic Resources in the Eggplant Wild Genepool

Access to high-throughput next-generation sequencing is now becoming affordable also for non-model crops and small laboratories. In addition, for the most important economic crops, their wild relatives are being sequenced and exploited for the introgression of important traits and to unravel the crops domestication history. Despite the importance of the three cultivated species in the eggplant genepool, common (Solanum melongena), scarlet (S. aethiopicum), and gboma eggplant (S. macrocarpon), genomic studies are still sparse. In this chapter, we reviewed the few genomic studies performed in the eggplant relatives, which are the primary source for the introgression of traits present in these wild relatives to develop resilient cultivated varieties to address the challenges of the present and future agriculture. In addition, we present the preliminary results of the first resequencing study of the eggplant wild relative S. incanum and compare it to the other seven accessions from the cultivated S. melongena. Among the set of these eight accessions, over 10 million polymorphisms were identified, most of them in the wild S. incanum, supporting the hypothesis of multiple genetic bottlenecks occurred during the domestication process that has led to narrowing the genetic diversity of the cultivated common eggplant compared to its wild counterparts. The distribution of the identified polymorphisms along the chromosomes revealed the footprints of ancient interspecific hybridizations events that occurred at a different chronology. The main goal of this chapter is to provide relevant genomics information for the enhancement and utilization of eggplant wild relatives in order to encourage eggplant breeders to develop and use new genomic tools as occurred in other economically important Solanaceae.