Campos Felipe G, Barzotto Gustavo R, Melo-Figueiredo Isabela, Pagassini Jonas A V, Boaro Carmen S F
Institute of Biosciences, São Paulo State University (UNESP), Campus Botucatu, Street Prof. Dr. Antonio Celso Wagner Zanin, 250-District de Rubião Junior, Botucatu 18618-689, SP, Brazil.
School of Agriculture, São Paulo State University (UNESP), Campus Botucatu, Ave. Universitária, n◦ 3780-Altos do Paraíso, Botucatu 18610-034, SP, Brazil.
Plants (Basel). 2025 Jul 7;14(13):2078. doi: 10.3390/plants14132078.
Hydrogen peroxide (HO) functions as a signaling molecule that triggers physiological and biochemical adjustments that help plants cope with environmental stress. This study evaluated the effects of foliar application of 1.5 mM HO on the physiological and biochemical responses of subjected to 14 days of drought stress followed by 5 days of rehydration. Drought reduced Fv/Fm and photochemical efficiency, as well as stomatal conductance and transpiration rates. HO treatment under drought further reduced stomatal conductance and transpiration, suggesting enhanced water conservation. Drought-stressed plants treated with HO exhibited increased concentrations of glucose, fructose, and mannose along with reduced sucrose levels, indicating osmotic adjustment and energy mobilization. Enzymatic antioxidant activity, particularly that of superoxide dismutase and catalase, increased with HO treatment, while peroxidase activity remained low. The content of vitexin, arabinose, and trehalose decreased under drought, likely due to their roles in membrane protection, as MDA levels remained stable. After rehydration, Fv/Fm and ΦPSII recovered, and HO-treated plants showed higher carbon assimilation and carboxylation efficiency. These results indicate that HO promotes drought acclimation and enhances post-stress recovery in . We conclude that HO induces signaling pathways, with trehalose, arabinose, and vitexin contributing to the regeneration of the photochemical apparatus, as well as defense and acclimation under drought conditions.
过氧化氢（H₂O₂）作为一种信号分子，可触发生理和生化调节，帮助植物应对环境胁迫。本研究评估了叶面喷施1.5 mM过氧化氢对经历14天干旱胁迫后再进行5天复水的植物生理和生化反应的影响。干旱降低了Fv/Fm和光化学效率，以及气孔导度和蒸腾速率。干旱条件下的过氧化氢处理进一步降低了气孔导度和蒸腾作用，表明其增强了水分保持能力。用过氧化氢处理的干旱胁迫植物表现出葡萄糖、果糖和甘露糖浓度增加，同时蔗糖水平降低，表明存在渗透调节和能量动员。酶促抗氧化活性，特别是超氧化物歧化酶和过氧化氢酶的活性，随着过氧化氢处理而增加，而过氧化物酶活性保持较低水平。干旱条件下牡荆素、阿拉伯糖和海藻糖的含量下降，可能是由于它们在膜保护中的作用，因为丙二醛水平保持稳定。复水后，Fv/Fm和ΦPSII恢复，用过氧化氢处理的植物表现出更高的碳同化和羧化效率。这些结果表明，过氧化氢促进植物的干旱适应并增强胁迫后恢复能力。我们得出结论，过氧化氢诱导信号通路，海藻糖、阿拉伯糖和牡荆素有助于光化学装置的再生以及干旱条件下的防御和适应。
