March 23, 2023
13h
Salle Ocean ( de Serres)
Climate change will exacerbate drought events in many regions, increasing the demand on freshwater resources and creating major challenges for viticulture. In viticulture, the terroir governs the hydraulic behavior of the vine. The terroir is defined as the interactions between climate, soil, plant material (vine and rootstock varieties) and human management practices. The knowledge on grapevine drought stress physiology has increased significantly in recent years, but a holistic comprehension on how soil-plant hydraulic resistances develop and are regulated remains poorly understood. In particular, how different soil-rootstock combinations and their plasticity affect the vine hydraulic condition is still an open question.
The objective of this study is to understand the hydraulics of the soil-plant system in grapevines (Vitis vinifera cv. Chardonnay) in situ, for different soil-rootstock combinations in a temperate oceanic climate, and to investigate its influence on vine water status. The concomitant and automatic monitoring of soil and collar water potentials, as well as sap flow, made it possible to characterize the evolution of the soil-vine hydraulics in situ in real-time, with hourly measurements for two months. The measurements were collected between mid-July and mid-September, during a period of exceptional drought in Belgium leading to soil water-limited conditions.