Genetic diversity and characterization of African eggplant germplasm collection

Genetic diversity among 70 “scarlet eggplant” (Solanum aethiopicum L.) entries from different geographical origins was assessed. Entries were firstly evaluated for the main morphologic traits and chlorogenic acid content. Standard statistics and multivariate analyses were utilized to assess the phenotypic diversity and grouping the entries. In addition, amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) analyses were used to evaluate genetic relationships among entries. Differences between entries are highly significant for all descriptors. Principal component analysis (PCA) revealed that the first three components accounted for 74% of the total variance. Morphologic traits were associated with the first two components, while the third one was moderately correlated with the chlorogenic acid content. The observed similarity allowed to identify only three main groupings. The clusters obtained did not show any relationships with geographic origins and/or botanical groups. Matrices of genetic similarity from AFLP and SSR data were utilized in order to obtain a dendrogram. A large cluster included several entries from South America with limited rate of genetic variation was observed. On the contrary, higher amount of variation was observed in the cluster with entries from Africa, in which are also present in the accessions collected in Italy. These entries appeared always morphologically and genetically distinguishable from the others. These results provided additional information for the conservation, improvement and legal protection of the ecotype ‘melanzana rossa di Rotonda’, cultivated in Italy.