Sahay Seema, de Bernardeaux Gabriel, Gamba Diana, Lasky Jesse R, Glowacka Katarzyna
Department of Biochemistry and Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, USA.
Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.
bioRxiv. 2025 May 18:2025.05.14.654125. doi: 10.1101/2025.05.14.654125.
Nonphotochemical quenching (NPQ) is a critical photoprotective mechanism in plants, safeguarding photosystem II (PSII) and PSI from photodamage under abiotic stress. However, it is unclear if different stressors lead to similar NPQ phenotypes, and the magnitude of natural variation (between and within plant species) in NPQ response to abiotic stress is unknown. Testing a semi-high-throughput leaf-disc approach for examining the NPQ kinetics parameters, we investigated NPQ under chilling, drought and low nitrogen stress across multiple species and/or genotypes. Our results show substantial variation in NPQ phenotypes across species, genotypes and treatments. In C3 crops, tobacco and soybean, multiple NPQ parameters generally increased under chilling and drought, while in C4 crops, maize and sorghum, NPQ traits were more variable including a decrease of multiple NPQ parameters. Low-N stress revealed genotype- and developmental stage-specific effects on NPQ, potentially reflecting distinct adaptive strategies and regulatory changes in NPQ stress response. A significant effect of ecotype and stress treatment was detected on most NPQ kinetics traits in , however, the interaction between ecotype and treatment was stronger in drought than in chilling. Differential regulation of NPQ could be associated with a combination of changes in proton motive, ATPase synthase activity, and PSI redox state. Our findings highlight that interpreting relative changes in NPQ under abiotic stress is inherently complex and demands a broader integration of physiological data across multiple regulatory layers.
非光化学猝灭（NPQ）是植物中一种关键的光保护机制，可在非生物胁迫下保护光系统II（PSII）和光系统I（PSI）免受光损伤。然而，尚不清楚不同的胁迫因子是否会导致相似的NPQ表型，并且NPQ对非生物胁迫响应的自然变异幅度（植物物种之间和物种内部）尚不清楚。通过测试一种用于检测NPQ动力学参数的半高通量叶盘法，我们研究了多种物种和/或基因型在低温、干旱和低氮胁迫下的NPQ。我们的结果表明，NPQ表型在物种、基因型和处理之间存在显著差异。在C3作物烟草和大豆中，多个NPQ参数在低温和干旱下通常会增加，而在C4作物玉米和高粱中，NPQ特征变化更大，包括多个NPQ参数的降低。低氮胁迫揭示了对NPQ的基因型和发育阶段特异性影响，这可能反映了NPQ胁迫响应中不同的适应策略和调控变化。在[具体物种]中，检测到生态型和胁迫处理对大多数NPQ动力学特征有显著影响，然而，生态型和处理之间的相互作用在干旱条件下比低温条件下更强。NPQ的差异调节可能与质子动力、ATP合酶活性和PSI氧化还原状态的变化组合有关。我们的研究结果强调，解释非生物胁迫下NPQ的相对变化本质上是复杂的，需要跨多个调控层面更广泛地整合生理数据。
