Identification and characterisation of traditional chestnut varieties of southern Spain using morphological and simple sequence repeat (SSRs) markers

The maintenance of plant genetic resources requires the identification of places and agroforestry systems that support high levels of genetic diversity. The aim of this work was to clarify the number and names of chestnut (Castanea sativa) cultivars in the south of Spain. Accordingly, 100 grafted chestnut trees corresponding to 34 traditional names were evaluated using 10 qualitative morphological traits and seven simple sequence repeat (SSRs) markers. We identified 38 varieties, 12 in the Huelva region and 26 in Malaga, and synonymies and homonymies were discussed. This work demonstrated that the joint use of morphological traits and SSR markers is an efficient method to evaluate the agrobiodiversity of chestnut in this region. It was also stated that chestnut production in the south of Spain is a traditional system using varieties developed 'in situ'. This constitutes a genuine system of on-farm conservation, which is now threatened. Consequently, adopting strategies for its safeguarding are urgently recommended.