Olive Tree (Olea europaea L.) diversity in traditional small farms of Ficalho, Portugal

Abstract

The genetic diversity of "Gama" and "Bico de Corvo", local cultivars of olive tree (Olea europaea) from seven traditional orchards of Ficalho (Alentejo region, Portugal), was studied to characterize the local diversity and assess the level of on farm diversity. Two different analytical systems were used: endocarp morphological characteristics and genetic analysis by microsatellite markers (Simple Sequence Repeats or SSR). The seven screened loci were polymorphic and allowed the identification of 23 distinct SSR profiles within the 27 trees analyzed. A total of 52 different alleles were scored, with an average of 7.43 alleles/SSR locus, and considerable genetic diversity was found. Neighbor-Joining algorithm cluster analysis and principal co-ordinate analysis (PCoA) allowed for the identification of the genetic relationships between several accessions. The 27 Olea accessions were clearly separated into three different groups. SSR analysis was more precise than endocarp characterization in the classification of genetic diversity among the olive tree cultivars. The study shows reasonable olive tree diversity in Ficalho, indicating that these traditional orchards are important reservoirs of old minor cultivars and incubators of new genotypes.