Abstract：
Andean ecosystems are characterized by high humidity, mainly from rain and fog events. Because of differences in altitude two Andean ecosystems - sub-Andean forest and Páramo -face different environmental pressures that affect leaf anatomy and cell wall composition and, consequently, species foliar water uptake (FWU) capacity. Here, FWU capacity of eight species in the Melastomataceae was evaluated and found to be related to proportions of cell wall components and aquaporins in the two ecosystems. Cellulose was labelled with Calcofluor white, and aquaporin and pectins were labelled with monoclonal antibodies. There were differences in plant FWU capacity in both ecosystems, with higher FWU capacity in sub-Andean forest species than in Páramo forest species. Cell wall components were positively related to FWU, with increased FWU related to pectin and aquaporin content of the plasma membrane. Differences in water availability in the two analysed environments led to differences in FWU capacity that are associated with leaf anatomical traits and cell wall composition. In these two environments, plants with similar traits are selected to respond to given environmental pressures. Traits that favour FWU in sub-Andean forest species may lead to further advances of these species in this environments.
摘要：
安第斯生态系统的特点是高湿度，主要来自雨雾事件。由于海拔高度的差异，两个安第斯生态系统-亚安第斯森林和帕拉莫-面临着影响叶片解剖结构和细胞壁组成的不同环境压力，因此,物种叶面吸水(FWU)能力。这里,评估了Melastomataceae中八个物种的FWU能力，发现其与两个生态系统中细胞壁成分和水通道蛋白的比例有关。纤维素被标记为Calcofluor白色，水通道蛋白和果胶用单克隆抗体标记。两种生态系统的植物FWU能力存在差异，安第斯亚森林物种的FWU能力高于Páramo森林物种。细胞壁组分与FWU呈正相干，FWU的增加与质膜中果胶和水通道蛋白含量有关。在两个分析的环境中，水分利用率的差异导致FWU能力的差异，这与叶片解剖特征和细胞壁组成有关。在这两种环境中,选择具有相似性状的植物来响应给定的环境压力。在安第斯亚森林物种中有利于FWU的特征可能会导致这些物种在这种环境中的进一步发展。
