Soil survey and continuous classification for terroir delineation in the “Colli Orientali del Friuli” wine production area

Da dove scaturisce tutto l’interesse attuale per il terroir? Si provi, per dare risposta a questo quesito, ad immaginare il vino avulso dalla sua dimensione territoriale. Cosa si otterrebbe? Un vino bianco, un vino rosso o quant’altro, ma comunque un prodotto privo di conno­tazione geografica, di premesse storiche, di radici tradizionali, di potere evocativo, di iden­tità e di personalità.

Enzymatic browning (BE) of must is caused by polyphenol oxidases (PPOs), tyrosinase and laccase. Both PPOs can oxidize diphenols such as hydroxycinnamic acids (HA) to quinones, which can later polymerize to form melanins [1], which are responsible of BE in white wines and of oxidasic haze in red wines. SO₂ is the main tool used to protect must from BE thanks to its capacity to inhibit PPOs [2]. However, the current trend in winemaking is to reduce and even eliminate this unfriendly additive. Among the different possible alternatives for protecting must against BE, the inoculation with a selected Metschnikowia pulcherrima MP1 is without any doubt one of the most promising ones.

Volatile organic compounds (VOCs) constitute a diverse group of secondary metabolites key for the communication of plants with other organisms and for their adaptation to environmental and biotic stresses. The emission of these compounds through leaves is also affected by the interaction of plants with symbiotic microorganisms, arbuscular mycorrhizal fungi (AMF) among them [1]. Our objective was to know the concentration and profile of VOCs emitted by the leaves of two grapevine varieties (Tempranillo, T, and Cabernet Sauvignon, CS, grafted onto R110 rootstocks), inoculated or not with a consortium of five AMF (Rhizophagus irregularis, Funneliformis mosseae, Septoglomus deserticola, Claroideoglomus claroideum and C. etunicatum).

Proximal sensors are becoming widely used in precision viticulture, due to the quick, easy and non-invasive identification of soil spatial variability. The apparent soil electrical conductivity (ECa) is the main parameter measured by sensors, which is correlated to many factors, like soil water content, salinity, clay content and mineralogy, rock fragments, bulk density, and porosity.

This work gives a summary of the most important programmes about viticultural « terroirs », developed on the « Côtes du Rhône » controlled appellation area for about twenty years.