Modélisation du régime thermique des sols de vignoble du Val de Loire : relations avec des variables utilisables pour la caractérisation des terroirs

The under-trellis zone of vineyards is a sensitive area through which vines cover a significant portion of their nutrient and water needs. Mechanical and chemical methods are applied to suppress competing and tall-growing weeds to ensure optimal vine growth conditions. In addition to higher operating costs and depending on the soil conditions, these practices might lead to a long-term reduction in soil fertility and biodiversity. The presented study aims to analyse the suitability and interspecies competition of a selected green cover mixture of five local herbaceous species as potential green cover mixture in the under-trellis area of Lower Austrian vineyards.

Vineyard yield forecasting is a key issue for vintage scheduling and optimization of winemaking operations. High errors in yield forecasting can be found in the wine industry, mainly due to the high spatial variability in vineyards, strong dependency on historical yield data, insufficient use of agroclimatic data and inadequate sampling methods

Under-vine (UV) management has traditionally consisted of synthetic herbicide use to limit competition between weeds and grapevines. With growing global interest towards non-synthetic chemical use, this study aimed to capture the effects of alternative UV management at two commercial Shiraz vineyards in South Australia, where the sole management variables were UV management since 2016. In adjacent treatment blocks, cultivation (CU) was compared to spontaneous vegetation (SV) in McLaren Vale (MV), and herbicide was compared to SV in Eden Valley (EV). Soil water infiltration rates were slower and grapevine stem water potential was lower in CU compared to SV in MV, with the latter having a plant community dominated by soursob (Oxalis pes-caprae) during winter; while in EV, there was little separation between the treatments. Yields were affected at both sites, with SV being higher in MV and HE being higher in EV. In MV, the only effect on grape must was a lower 13C:12C isotope ratio in CU, indicating greater grapevine water stress. In the grape must at EV, SV had higher total soluble solids, total phenolics, anthocyanins, and yeast available nitrogen; and lower pH and titratable acidity. Pruning weights were not affected by the treatments in MV, while they were higher in HE at EV. Assessments revealed that the differing soil types at the two sites were likely the main determinants of the opposing production outcomes associated with UV management. In the silty loam soil of MV, the higher yields in SV were likely due to more plant-available water, as a potential result of the continuous soil bio-pores formed by winter UV vegetation. Conversely, in the loamy sand soils of EV with a lower cation exchange capacity, the lower yields and pruning weights in SV suggest the UV vegetation competed significantly with the grapevines for available water and nutrients.

Chasselas is a refined grape variety renowned for its subtlety and its remarkable ability to reflect terroir characteristics [1]. Typically consumed young, it is appreciated for its low acidity and delicate fruity and floral aromas.

Obiettivo del progetto è la valutazione dell’influenza climatica e pedologica dell’areale di Montefalco sul vitigno Sagrantino, ponendo particolare attenzione alla componente polifenolica e antocianica. Sono stati quindi messi a confronto, a partire dal 2001 fino al 2008, sei differenti zone tutte situate all’interno dell’areale DOCG Sagrantino di Montefalco; per ciascun vigneto alla vendemmia sono state effettuate analisi sui parametri analitici e sul contenuto polifenolico e antocianico delle uve. Ognuna delle sei zone è inoltre stata caratterizzata dal punto di vista pedoclimatico, valutando l’influenza del clima e della tipologia di suolo sui parametri analitici presi in considerazione.