Genotyping ex situ trees of Abies nebrodensis translocated from the original Sicilian population to enrich the gene pool

As a dynamic ex situ conservation strategy, a clonal seed orchard was started in a nursery in Pomaio (POM) in central Italy in 1993 for an assisted migration experiment of Abies nebrodensis (Lojac.) Mattei. Two artificial ex situ populations were planted with this gene pool: a seedling arboretum in Pieve Santo Stefano (PSS) and a small dendrological collection in Papiano (PAP), both originating from the Sicilian relict population. Here, using AFLP markers, we estimated the relatedness among the relocated genotypes of the three collections to check whether the three collections had sufficient genetic variability to be considered as additional sources of variability to the original gene pool for the assisted migration strategy. High individual genetic variability was found in the collections; each plant had a different genotype and was confirmed to belong to its population of origin. PAP and PSS trees were shown to be only from the original population of A. nebrodensis species and were derived from a limited set of maternal fertile genotypes. Based on the Sicilian fir population inventory, nursery production in Sicily, and structure clustering analysis, close genetic relationships among POM, PAP and several PSS trees (1–35) were evident. Similarly, the PSS group (36–78) was genetically close to tree 1 of POM and in a lesser proportion to plants 7 and 9 of POM. The sampling of seedlings used to form batches in the nursery might have influenced the structure of the resultant plantations. All genotypes will be useful for enriching the original gene pool.