Censimento e descrizione del germoplasma di Castanea sativa cv di Marrone di Chiusa di Pesio

Chestnuts have been for a long time a primary economical resource for Italian country, especially for Piedmont. One of the most important and appreciated cultivar of Castanea sativa is the Marrone of Chiusa di Pesio, that grows only in Pesio valley in Piedmont but from the nineteenth century it has been sold throughout the Italian country. The purpose of the study, commissioned by the municipality of Chiusa di Pesio with the partnership of the University of Turin and of the Regional Chestnut Center, is to identify and locate plants of Marrone of Chiusa di Pesio in the original area. With the data obtained, a specific cartography has been produced. During the work, 20 samples of Marrone di Chiusa di Pesio were analyzed: DNA extraction was carried out from the leave and a Visual Tree Assessment (VTA) form was compiled in order to evaluate the current situation of the culture and the morphological status of plants. Subsequently, morphological analysis of the inside and outside part of the fruits were carried out using the descriptors International Union for the Protection of New Varieties of Plants (UPOV). In addition, some fruits were processed to obtain flour in order to evaluate the nutritional value of the crop with some chemical analysis. From the study 187 trees of Marrone di Chiusa di Pesio have been identified, mainly located in a small, flat area called Regione Vigne in the municipality of Chiusa di Pesio. From the DNA analysis of the 20 samples emerged that 19 are plants of C. sativa cv Marrone di Chiusa di Pesio. Through the VTA analysis it was found that the current morphological condition of the plant is not optimal. The presence of pathologies (Cryphonectria parasitica (Murr.); Phytophthora cambivora (Petri) Buisme e P. cinnamoni Rand (Crandall, l.c.)) conditions the health state of plants. In addition, plants are old: more than 70% of plants can be dated back to the second post-war period, only one chestnut orchard has less than ten years. From morphological analysis of the fruits has emerged a correlation between characteristics of the fruit and cultural techniques used. In particular, the phytosanitary status and the lack of irrigation influence morphological characteristics of the fruit. Otherwise, nutraceutical characteristics of the fruit don't depend on cultural techniques used. In conclusion, an adequate plane of recovery, maintenance and renovations could lead the culture to be an important economical resource.