Genetic and landscape characterization of ancient autochthonous olive trees in northern Italy

Several ancient olive plants with different genetic, agronomic and morphological characteristics are widespread in the Emilia-Romagna region. In this study, details of 206 trees located in four provinces were collected and their phytometric traits were recorded. Easily recognizable varieties were identified, while plants of uncertain genetic identity were submitted for molecular analysis with SSR markers and compared with cultivars widespread in central Italy and Emilia-Romagna. The genetic analyses showed that most of the ancient olive trees belonged to 10 cultivars that are already characterized, with different cases of intra-varietal clones. The remaining accessions belonged to 19 different genotypes of unknown origin. The highest percentage of policormic trees was found in the Bologna and Rimini provinces. A high percentage of plants located under unfavourable aspects (west to east) was found only in the Rimini territory, which presents peculiar and milder climatic conditions compared to the other provinces. Slope appeared not to be a limiting factor for tree survival. The information obtained could help the rational reintroduction of olive growing in suitable areas of Emilia-Romagna, with the subsequent economic advantages, erosion preservation and germplasm enrichment.