In an altitudinal Brazilian ecosystem, fog is a frequent event in both the dry and rainy seasons. The drought stress is aggravated in the dry season due to elevated evaporative demand and this constraint can induce oxidative stress in plants. In this ecosystem, there are plants which present different foliar water uptake (FWU) capacities - species that absorb less water more quickly (LQ) and those that absorb more water more slowly (MS). In this study, the relationship between oxidative stress responses and the different FWU strategies was evaluated in dry and rainy seasons. The oxidative stress was assessed by H2O2 production and lipid peroxidation as well as by the antioxidant enzymes system as superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). During the dry season, plants had higher oxidative stress compared to rainy season plants which exhibited moderate oxidative damage. The FWU strategies were closely related to oxidative stress responses, since the LQ species presented the higher H2O2 content and oxidative defense system. Contrastingly, it was found that MS species have the lowest values of H2O2 and less SOD, CAT and APX activities. However, the lipid peroxidation did not present any relation with FWU strategies. Altogether results revealed that plants, which present MS strategy, are more adapted to cope with the higher H2O2 concentrations generated in the dry season and drought stress events than those that present LQ strategy.

中文翻译：

---

在干旱和雨季，巴西树种田植物的氧化代谢及其与叶面水分吸收的关系。

在巴西的一个高海拔生态系统中，无论在雨季还是雨季，雾都是经常发生的事件。由于蒸发需求的增加，干旱季节的干旱胁迫加剧了，这种限制会在植物中诱发氧化胁迫。在这个生态系统中，有些植物表现出不同的叶片吸水量（FWU）-吸收更快的水更快的物种（LQ）和吸收更快的水更快的物种（MS）。在这项研究中，在干旱和雨季评估了氧化应激反应和不同的FWU策略之间的关系。通过H2O2的产生和脂质过氧化以及通过抗氧化剂酶系统（如超氧化物歧化酶（SOD），过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX））来评估氧化应激。在旱季，与雨季植物相比，这些植物具有较高的氧化应激，而雨季植物表现出中等程度的氧化损伤。FWU策略与氧化应激反应密切相关，因为LQ物种表现出更高的H2O2含量和氧化防御系统。相反，发现MS物种具有最低的H2O2值，而SOD，CAT和APX活性较低。但是，脂质过氧化与FWU策略没有任何关系。总体结果显示，与采用LQ策略的植物相比，采用MS策略的植物更能适应干旱季节和干旱胁迫事件中产生的更高的H2O2浓度。由于LQ物种具有较高的H2O2含量和氧化防御系统。相反，发现MS物种具有最低的H2O2值，而SOD，CAT和APX活性较低。但是，脂质过氧化与FWU策略没有任何关系。总体结果显示，与采用LQ策略的植物相比，采用MS策略的植物更能适应干旱季节和干旱胁迫事件中产生的更高的H2O2浓度。由于LQ物种具有较高的H2O2含量和氧化防御系统。相反，发现MS物种具有最低的H2O2值，而SOD，CAT和APX活性较低。但是，脂质过氧化与FWU策略没有任何关系。总体结果显示，与采用LQ策略的植物相比，采用MS策略的植物更能适应干旱季节和干旱胁迫事件中产生的更高的H2O2浓度。