the French Associates Institute for Agriculture and Biotechnology of Drylands (FAAB), the Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, 84990 Sede Boqer, Israel.
BMC Plant Biol. 2013 Nov 20;13:184. doi: 10.1186/1471-2229-13-184.
Grapevine metabolism in response to water deficit was studied in two cultivars, Shiraz and Cabernet Sauvignon, which were shown to have different hydraulic behaviors (Hochberg et al. Physiol. Plant. 147:443-453, 2012).
Progressive water deficit was found to effect changes in leaf water potentials accompanied by metabolic changes. In both cultivars, but more intensively in Shiraz than Cabernet Sauvignon, water deficit caused a shift to higher osmolality and lower C/N ratios, the latter of which was also reflected in marked increases in amino acids, e.g., Pro, Val, Leu, Thr and Trp, reductions of most organic acids, and changes in the phenylpropanoid pathway. PCA analysis showed that changes in primary metabolism were mostly associated with water stress, while diversification of specialized metabolism was mostly linked to the cultivars. In the phloem sap, drought was characterized by higher ABA concentration and major changes in benzoate levels coinciding with lower stomatal conductance and suberinization of vascular bundles. Enhanced suberin biosynthesis in Shiraz was reflected by the higher abundance of sap hydroxybenzoate derivatives. Correlation-based network analysis revealed that compared to Cabernet Sauvignon, Shiraz had considerably larger and highly coordinated stress-related changes, reflected in its increased metabolic network connectivity under stress. Network analysis also highlighted the structural role of major stress related metabolites, e.g., Pro, quercetin and ascorbate, which drastically altered their connectedness in the Shiraz network under water deficit.
Taken together, the results showed that Vitis vinifera cultivars possess a common metabolic response to water deficit. Central metabolism, and specifically N metabolism, plays a significant role in stress response in vine. At the cultivar level, Cabernet Sauvignon was characterized by milder metabolic perturbations, likely due to a tighter regulation of stomata upon stress induction. Network analysis was successfully implemented to characterize plant stress molecular response and to identify metabolites with a significant structural and biological role in vine stress response.
在两个品种（设拉子和赤霞珠）中研究了葡萄藤对水分胁迫的代谢反应，这两个品种的水力行为不同（Hochberg 等人，《植物生理学》147:443-453，2012）。
发现渐进性水分胁迫会导致叶片水势发生变化，并伴有代谢变化。在两个品种中，设拉子比赤霞珠更为明显，水分胁迫导致渗透压升高和 C/N 比降低，后者也反映在氨基酸（如 Pro、Val、Leu、Thr 和 Trp）显著增加、大多数有机酸减少以及苯丙烷途径的变化。PCA 分析表明，初级代谢的变化主要与水分胁迫有关，而特殊代谢的多样化主要与品种有关。在韧皮部汁液中，干旱的特征是 ABA 浓度升高，苯甲酸盐水平发生重大变化，同时气孔导度降低，维管束木质化。设拉子木质素生物合成增强反映在韧皮部羟基苯甲酸衍生物的丰度更高。基于相关性的网络分析表明，与赤霞珠相比，设拉子在压力下具有更大、更协调的变化，反映在其胁迫下代谢网络连通性增加。网络分析还突出了主要与胁迫相关的代谢物的结构作用，例如 Pro、槲皮素和抗坏血酸，它们在水分胁迫下在设拉子网络中的连接性发生了剧烈变化。
综上所述，结果表明，葡萄品种对水分胁迫具有共同的代谢反应。中心代谢，特别是氮代谢，在葡萄藤的应激反应中起着重要作用。在品种水平上，赤霞珠的代谢干扰较轻，可能是由于在胁迫诱导时对气孔的调控更严格。网络分析成功地用于表征植物应激分子反应，并确定在葡萄应激反应中具有重要结构和生物学作用的代谢物。
