Study of Biodiversity for Fruit Valorisation: the example of Ancient Apple Cultivars (Malus x domestica Borkh.) from Tuscany (Italy)

The development of intensive cultivation favoured the introduction in the modern orchards of only few cultivars that make possible the standardization of production. This turn out in the loss of attention on the most local germplasm that, being the result of centuries of selection and adaptation to the local environmental conditions, can be an interesting source of genes for breeding programs and for the production of value-added cultivars. In this perspective, discovery, identification and conservation of endangered plant genetic resources is important to preserve biodiversity of less common cultivars from the risk of genetic erosion. Apple (Malus x domestica Borkh.) is one the most commonly consumed fruits worldwide. Due to its high content in polyphenols, this fruit is an important source of antioxidants in the human diet. This work started with the aim to clarify the entity of ancient apple varieties from Casentino area (Tuscany, Italy). A survey and a morphological classification of 135 ancient apple accessions were carried out in this territory: 75 genotypes have been selected among these for molecular characterization by 5 SSR markers. The analysis showed a huge genetic variability within the local germplasm and explained the relationships among genotypes. Twenty percent of unique alleles were found out of the total alleles number, highlighting the genetic uniqueness of this plant material and confirming its high potential as genetic source for the improvement of species. With the aim to increase the value of this local germplasm by a nutritional approach, antioxidant properties of fruit were evaluated in the 4 most representative ancient apple cultivars. The analyses highlighted a higher content in total polyphenols and flavonoids in the old local cultivars than in the commercial varieties Golden Delicious and Stark Delicious. Also the antioxidant activity was significant higher in two local cultivars than in the other, highlighting the nutritional value of these forgotten genotypes.