Multi-hormonal analysis and aquaporins regulation reveal new insights on drought tolerance in grapevine

作者：Riccardo Braidotti, Rachele Falchi, Alberto Calderan, A Pichierri, Radomı́ra Vaňková, Petre I. Dobrev, Michaela Griesser, Paolo Sivilotti · 发表于：Journal of Plant Physiology · 年份：2024 · DOI：10.1016/j.jplph.2024.154243 · 被引用次数：15 · 研究领域：Plant Water Relations and Carbon Dynamics、Horticultural and Viticultural Research、Plant Stress Responses and Tolerance

Disentangling the factors that foster the tolerance to water stress in plants could provide great benefits to crop productions. In a two-year experiment, two new PIWI (fungus resistant) grapevine varieties, namely Merlot Kanthus and Sauvignon Kretos (Vitis hybrids), grown in the field, were subjected to two different water regimes: weekly irrigated (IR) or not irrigated (NIR) for two months during the summer. The two varieties exhibited large differences in terms of performance under water-limiting conditions. In particular, Merlot Kanthus strongly decreased stem water potential (Ψs) under water shortage and Sauvignon Kretos maintained higher Ψs values accompanied by generally high stomatal conductance and net carbon assimilation, regardless of the treatment. We hypothesized differences in the hormonal profile that mediate most of the plant responses to stresses or in the regulation of the aquaporins that control the water transport in the leaves. In general, substantial differences were found in the abundance of different hormonal classes, with Merlot Kanthus reporting higher concentrations of cytokinins while Sauvignon Kretos higher concentrations of auxins, jasmonate and salicylic acid. Interestingly, under water stress conditions ABA modulation appeared similar between the two cultivars, while other hormones were differently modulated between the two varieties. Regarding the expression of aquaporin encoding genes, Merlot Kanthus showed a significant downregulation of VvPI...