[eng] Water scarcity is one of the main challenges in vineyards sustainability in most of the
grapevine áreas, now and even more in near future to due climatic change perspectives.
For that reason, water use efficiency measurements are one of the highest interest to
improve the sustainability of this crop. Since the vast majority of studies relays on
measurements of carbon and water fluxes at the leaf scale, less data are available at the
whole-plant scale.
For this reason, in this experiment, whole-plant water and carbon fluxes in grapevine
exposed to two different water regimes and under high CO2 concentrations were
measured, in order to check its effect at the whole-plant scale.
The results obtained showed that water and carbon fluxes are well coordinated between
themselves under both water treatments. Under drought conditions, both fluxes were
reduced, but surprisingly the estimated water use efficiency was decreased, contrarily to
what is shown at the leaf scale. Finally, high CO2 measurements indicated an increase
of whole-plant NCE as well as increased whole-plant water use efficiency, mainly in
non-watered plants.