Plant response to drought is a complex phenomenon consisting of numerous metabolic pathways primarily based on water loss prevention and redox homeostasis maintenance. This study analyses the correlation of stomatal and non-stomatal carbon assimilation-limiting mechanisms with the strategies in antioxidant metabolism pathways and their connection with anatomical modifications in tomato leaves during long-term drought period lasting over 28 days. The results obtained in this research indicate that activation of stomatal closure was the first response to drought as stomatal pore was narrowed by 20% in day 15. The stomatal closing in early stress response was followed by decline in photosynthetic and transpiration rates even though the RUBISCO content has not been changed. Along with drought stress, both stomatal closure and RUBISCO content dramatically decreased leading to a decline in gas exchange parameters; thus, at the end of the experimental Queryperiod, the photosynthetic rate was reduced by 69% and transpiration rate by 80% in comparison with control plants. Superoxide dismutase and ascorbate peroxidase were induced in early stress response (as soon as after 15 days) with a constantly elevated activity during entire drought period. Terminal phase of drought induced the synthesis of new peroxidase isoform (MW ~ 49 kDa) which highly correlated with the phenolic acid contents. At the end of experimental period, the total phenol content of drought-treated plants was doubled as compared to control plants and this increase is correlated to elevated concentrations of hydroxybenzoic acid, ferulic acid, p-coumaric acid and caffeic acid. The progressive involvement of different antioxidant mechanisms over the drought period and their correlations with anatomical modifications and photosynthetic pigments protection was discussed in this paper.

植物对干旱的反应是一个复杂的现象，主要由预防水分流失和维持氧化还原稳态组成，由许多代谢途径组成。本研究分析了长期干旱持续超过28天的番茄叶片气孔和非气孔碳同化限制机制与抗氧化剂代谢途径策略的关系及其与番茄叶片解剖结构的联系。该研究获得的结果表明，气孔关闭的激活是对干旱的第一个反应，因为在第15天气孔孔隙缩小了20％。即使在RUBISCO的作用下，气孔关闭在早期胁迫反应中也会随之光合和蒸腾速率下降。内容未更改。除干旱外，气孔关闭和RUBISCO含量急剧下降，导致气体交换参数下降；因此，在实验查询期结束时，与对照植物相比，光合速率降低了69％，蒸腾速率降低了80％。超氧化物歧化酶和抗坏血酸过氧化物酶被诱导在早期胁迫反应中（最快在15天后），并在整个干旱期间不断升高的活性。干旱的末期诱导了新的过氧化物酶同工型（MW〜49 kDa）的合成，其与酚酸含量高度相关。在实验期结束时，与对照植物相比，干旱处理植物的总酚含量增加了一倍，并且这种增加与羟基苯甲酸，阿魏酸，p-香豆酸和咖啡酸。本文讨论了干旱时期不同抗氧化剂机制的逐步参与及其与解剖修饰和光合色素保护的关系。