Comparison of different methodologies in order to perform a representative Cynara cardunculus L. core collection

Abstract

his study was carried out in order to compare different methodologies to select a representative core collection from an initial collection of Cynara cardunculus L. species, using both morphological and molecular markers. The combination of two stratification criteria with three sampling strategies allowed the establishment of six different core collections. The Maximization strategy was applied in order to obtain the seventh one. All the obtained collections were validated through phenotypic and molecular parameters, establishing as an initial criterion that the core collection should include, at most, 35-40 % of the accessions belonging to the original collection. All collections passed molecular validation; nevertheless morphological validation determined that the Proportional sampling strategy is the best to keep the initial variability while retaining the least number of accessions, especially when combined with the first stratification criterion. Although Maximization strategy allowed to preserve the original variability, it retained the largest number of accessions. In conclusion, the combination PrS1 (proportional sampling and first stratification criterion) is the best strategy to perform a representative core collection from a Cynara cardunculus L. initial collection, using both morphological and molecular data.