Huo Haixia, Jaffar Muhammad Tauseef, Zhang Jianguo, Shang Jianxuan
College of Hydraulic Engineering, Shaanxi A&F Technology University, Yangling, China.
College of Natural Resources and Environment, Northwest A&F University, Yangling, China.
Front Plant Sci. 2025 Aug 7;16:1640412. doi: 10.3389/fpls.2025.1640412. eCollection 2025.
Understanding plants responses to drought stress is crucial for selecting appropriate species for shelter-forest construction in arid and semi-arid regions. , one of the most planted shrubs along the Taklimakan Desert Highway Shelterbelt (TDHS), contributes significantly to maintaining the highway's ecological stability. This study aimed to investigate the physiological responses of biennial seedlings to drought stress by monitoring changes in soil moisture and chlorophyll fluorescence parameters [actual photo chemical efficiency of PSII (Y), unregulated energy dissipation quantum yield (Y), non-photochemical quenching coefficient (NPQ), and regulatory energy dissipation quantum yield (Y] under controlled conditions. The results showed that soil moisture declined progressively with prolonged drought stress. Although the photosystem II (PSII) reaction centers of the seedlings experienced some stress after 30 days of drought, no irreversible photodamage occurred. However, the risk of photoinhibition and damage to the photosynthetic apparatus increased with prolonged drought, as evidenced by an increase in NPQ. These findings suggest that seedlings adapt to drought stress by modulating their chlorophyll fluorescence characteristics, enhancing our understanding of its drought adaptation mechanisms and highlighting the need for future research on its long-term physiological responses under field conditions and varying drought intensities.
了解植物对干旱胁迫的反应对于在干旱和半干旱地区选择合适的物种进行防护林建设至关重要。胡杨是塔克拉玛干沙漠公路防护林带（TDHS）沿线种植最多的灌木之一，对维持公路的生态稳定性有重要贡献。本研究旨在通过监测在可控条件下土壤水分和叶绿素荧光参数[PSII的实际光化学效率（Y）、非调节性能量耗散量子产率（Y）、非光化学猝灭系数（NPQ）和调节性能量耗散量子产率（Y）]的变化，来研究二年生胡杨幼苗对干旱胁迫的生理反应。结果表明，随着干旱胁迫时间的延长，土壤水分逐渐下降。虽然干旱30天后幼苗的光系统II（PSII）反应中心受到了一些胁迫，但未发生不可逆的光损伤。然而，随着干旱时间的延长，光抑制和光合机构受损的风险增加，NPQ的增加证明了这一点。这些发现表明，胡杨幼苗通过调节其叶绿素荧光特性来适应干旱胁迫，增进了我们对其干旱适应机制的理解，并突出了未来在田间条件和不同干旱强度下对其长期生理反应进行研究的必要性。
