A multi-trait characterization of the 'Friariello' landrace: A Mediterranean resource for sweet pepper breeding

Landraces are an important resource for crop breeding, due to their resilience and content of quality traits. However, genetic and phenotypic variability needs to be carefully characterized for proper direct and indirect use. In the present study, a multidisciplinary approach was carried out to assess the Italian sweet pepper landrace 'Friariello'. A total of 18 traditional accessions were compared with five hybrids and two ecotypes with similar fruit typology. Genetic and morpho-agronomic characterization allowed us to distinguish five different group types of 'Friariello'. Accessions showing two/three lobes at the blossom end of the fruit were found to be the most productive, whereas the genotypes showing one/two lobes at the blossom end were the most homogeneous. A total of 167 volatile organic compounds (VOCs) were identified in the collection analysed. Moreover, of the 37 targeted VOCs, 29 showed significant differences in content among the pepper genotypes studied. Of such VOCs related to main flavours described for pepper in the literature, ten were found to be the major determinants of variability among the derived 'Friariello' groups. A slightly negative, albeit not significant, correlation was observed between ascorbic acid (AsA) content and agronomic traits, suggesting a better quality for less productive accessions, but also the possibility to improve yield without significantly reducing the AsA levels. The approach used allowed us to define how the different typologies can be used for different breeding purposes, integrating the peculiar properties in order to establish a desirable landrace ideotype. Furthermore, valuable sources for improving quality traits in pepper breeding were identified.