The large diversity of grapevine cultivars includes genotypes more tolerant to water deficit than others. Widely distributed cultivars, like Merlot, are more sensitive to water deprivation than local cultivars like Callet, which are more adapted to water deficit due to their Mediterranean origin. Despite their tolerance, adaptation to water deficit influenced by grafting in rootstocks like 110 Richter is key to facing drought in vineyards, defining the scion/rootstock relationship. To understand these differences, we explored transcriptomic, metabolic, hormonal and physiological responses under three levels of water deficit (mild, high and extreme), using 110 Richter as the rootstock in both cultivars. Results revealed that sensitivity to ABA is essential for water deficit tolerance in the aerial part, guiding root responses. Callet/110 Richter activates more gene expression patterns in response to ABA, reducing water loss compared to Merlot/110 Richter in both aerial and root parts. This modulation in Callet/110 Richter involves regulating metabolic pathways to increase cell turgor, reducing photosynthesis, and producing molecules like polyphenols or flavonoids to respond to oxidative stress. In contrast, Merlot/110 Richter shows a lack of specific response, especially in the roots, indicating less resilience to water stress. Therefore, selecting genotypes more sensitive to ABA and their interaction with rootstocks is key for managing vineyards in future climate change scenarios.

中文翻译：

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接穗驱动的转录组变化指导嫁接近等氢葡萄藤在缺水情况下的恢复力


葡萄品种的种类繁多，包括比其他品种更耐水亏的基因型。广泛分布的栽培品种，如梅洛，比像 Callet 这样的当地栽培品种对缺水更敏感，后者由于起源于地中海而更适应水分短缺。尽管它们具有耐受性，但适应受 110 Richter 等砧木嫁接影响的水分亏缺是葡萄园面临干旱的关键，定义了接穗/砧木的关系。为了了解这些差异，我们以 110 Richter 作为两个品种的砧木，探讨了三个缺水水平（轻度、高度和极端）下的转录组学、代谢、激素和生理反应。结果显示，对 ABA 的敏感性对于地上部分的缺水耐受性至关重要，指导根反应。Callet/110 Richter 响应 ABA 激活更多的基因表达模式，与 Merlot/110 Richter 相比，减少了地基和根部的水分流失。Callet/110 Richter 中的这种调节涉及调节代谢途径以增加细胞弹性、减少光合作用以及产生多酚或类黄酮等分子来响应氧化应激。相比之下，梅洛/110 Richter 表现出缺乏特异性反应，尤其是在根部，表明对水分胁迫的恢复力较差。因此，选择对 ABA 及其与砧木相互作用更敏感的基因型是在未来气候变化情景中管理葡萄园的关键。