Cultivation of grapes Chardonnay in soils with management practices biodynamic and conventional

Aim‐ Rootstocks provide protection against soil borne pests and are a powerful tool to manipulate growth, fruit composition and wine quality attributes

En Anjou, une méthode de caractérisation des terroirs viticoles a été développée. Elle utilise un modèle de terrain basé sur la profondeur de sol et son degré d’argilisation.

L’AOC Grignolino d’Asti (20000 hl environ de production) est un vin de la province de Asti, produit avec le raisin rouge du cépage de même nom originaire du Piémont (Nord-Ouest d’Italie).

Grapevine, Vitis vinifera, requires grafting on Phylloxera tolerant rootstocks of American origin in most viticultural areas of the world. The most commonly used species in rootstock creation are V. berlandieri, V. riparia and V. rupestris. Rootstocks not only provide tolerance to Phylloxera but assure the supply of water and mineral nutrients to the scion. The objective of this work was to determine to what extent rootstocks of different parentages alter the mineral composition of petioles of grapevine.

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.