Water deficit limits grapevine water uptake. However, the quantitative contribution of drought to vine water requirements is largely uncharacterized. Thus, we set to explore whole-plant water use during short-term drought events and recovery and associate the proportional reduction in transpiration with changes in vine physiological attributes. We hypothesized that short drought events pose long-term restrictions to transpiration through limitations to canopy development and stomatal conductance (g_s).

We used large (2 m³) weighing lysimeters to measure how three short (six-seven days) drought events affected seasonal vine transpiration. We additionally measured the interactions between vine leaf area index (LAI), available water (AW), g_s, or stem water potential (SWP) with transpiration (ET) during drought and recovery.

Three recurrent drought events reduced seasonal ET by 848 L vine⁻¹ (11% of the seasonal uptake). Nevertheless, only 50% of the transpiration losses were an immediate response to the drought, while the other half occurred after rehydration, apparently due to lower g_s and LAI. The stress coefficient (K_S) correlated with g_s and SWP during drought, though their interactions depended on phenology and varied from previous reports. The effect of drought on plant water uptake extended beyond the immediate water limitation and affected vines for the remaining season. Practically, LAI measurements could project most of the long-term ET limitations. While the variability of Ks response to changes in g_s or SWP may result in a 16% or 20% error, respectively, the generalized models presented remain the most comprehensive and inclusive options available for predicting grapevine water uptake under drought.

缺水限制了葡萄树的水分吸收。然而，干旱对葡萄树水分需求的定量贡献在很大程度上是未知的。因此，我们着手探索短期干旱事件和恢复期间整株植物的用水情况，并将蒸腾作用的减少与葡萄生理属性的变化联系起来。我们假设短期干旱事件通过限制冠层发育和气孔导度 (g _s ) 对蒸腾作用造成长期限制。

我们使用大型（2 m ³）称重蒸渗仪来测量三个短时间（六七天）的干旱事件如何影响季节性葡萄树的蒸腾作用。_{我们还测量了干旱和恢复期间葡萄叶面积指数 (LAI)、可用水 (AW)、g s}或茎水势 (SWP) 与蒸腾 (ET)之间的相互作用。

三个反复发生的干旱事件使季节性 ET 减少了 848 L vine ^-1（季节性吸收的 11%）。然而，只有 50% 的蒸腾损失是对干旱的直接反应，而另一半发生在再水化之后，显然是由于较低的 g _s和 LAI。胁迫系数 (K _S )在干旱期间与 g _s和 SWP相关，尽管它们的相互作用取决于物候并且与以前的报告不同。干旱对植物吸水的影响超出了直接的水限制，并影响了剩余季节的葡萄藤。实际上，LAI 测量可以预测大部分长期 ET 限制。_{而 Ks 响应 g s}变化的可变性或 SWP 可能分别导致 16% 或 20% 的误差，所提出的广义模型仍然是预测干旱条件下葡萄吸水量的最全面和包容性的选择。