Key Laboratory for Bio-resource and Eco-environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610065, China.
Physiol Plant. 2023 Mar;175(2):e13890. doi: 10.1111/ppl.13890.
Drought is an important stress factor that limits plant growth and development. Female willows generally display stronger drought tolerance than males. The application of exogenous acetic acid (AA) has emerged as an efficient and eco-friendly approach to facilitate drought tolerance in willows. However, whether AA exerts sexually different effects on willows remains undefined. In this study, we comprehensively performed morphological and physiological analyses on three willow species, Salix rehderiana, Salix babylonica, and Salix matsudana, to investigate the sexually different responses to drought and AA. The results indicated that willow females were more drought-tolerant than males. AA application effectively enhanced willows' drought tolerance, and females applied with AA displayed greater root distribution and activity, stronger osmotic and antioxidant capacity and photosynthetic rate but less reactive oxygen species, or abscisic acid-mediated stomatal closure than males. In addition, AA application enhanced the jasmonic acid signaling pathway in females but inhibited it in males, conferring stronger drought defense capacity in female willows than in males. Overall, AA application improves drought tolerance more in female than in male willows, further enlarging the sexual differences in willows under drought-stressed conditions.
干旱是限制植物生长和发育的重要胁迫因素。雌柳树通常比雄柳树具有更强的耐旱性。外源乙酸（AA）的应用是一种促进柳树耐旱性的有效且环保的方法。然而，AA 是否对柳树表现出性别差异的影响尚不清楚。在这项研究中，我们对三种柳树品种（垂柳、垂柳和毛白杨）进行了全面的形态和生理分析，以研究柳树对干旱和 AA 的性别差异响应。结果表明，柳树雌株比雄株更耐旱。AA 的应用有效地增强了柳树的耐旱性，与雄性柳树相比，应用 AA 的雌性柳树具有更大的根系分布和活性、更强的渗透和抗氧化能力以及更高的光合速率，但产生的活性氧或脱落酸介导的气孔关闭较少。此外，AA 的应用增强了雌性柳树中的茉莉酸信号通路，但抑制了雄性柳树中的该通路，从而赋予雌性柳树比雄性柳树更强的干旱防御能力。总的来说，AA 的应用在雌性柳树中比在雄性柳树中更能提高耐旱性，进一步扩大了柳树在干旱胁迫条件下的性别差异。
