Abstract G-fibers have been widely studied in tension wood, but few studies are available on aerial and underground organs of shrub and subshrub, specially comparing those organs of the same plant. The goal of this study is to compare the general pattern of G-fibers distribution, and the structure and histochemistry of G-fibers walls between aerial and underground organs in 19 Eriosema taxa occurring in the tropical savanna, locally called cerrado. The samples were processed according to standard techniques in plant anatomy and histochemistry. G-fibers occurred throughout the vegetative body and were exclusively extraxylary in organs with primary growth and extraxylary and xylary in organs with incipient secondary growth. G-fibers were more abundant and had a thicker G-layer in the underground organs. In all the organs analyzed, the G-fibers were identified by the presence of a non-lignified internal translucent layer (G-layer) sometimes occupying the entire lumen of the fiber. The abundance and wide occurrence of G-fibers in the vegetative axis of Eriosema plants may represent an adaptive mechanism and may explain why plants that belong to this genus are able to survive in adverse Cerrado conditions. We suggest that the conditions of the Cerrado environment may stimulate the differentiation of gelatinous fibers in these plants. In addition, the ecophysiological significance of the G-fibers, we emphasize their taxonomic value as a unifying character of the Eriosema genus.

中文翻译：

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Eriosema (DC.) Desv 中凝胶状纤维的结构和组织化学变化。来自巴西塞拉多的（豆科）物种

摘要 G-纤维在抗张木中得到了广泛的研究，但对灌木和亚灌木的地上和地下器官的研究很少，特别是对同一植物的这些器官进行比较。本研究的目的是比较 G 纤维分布的一般模式，以及在热带稀树草原（当地称为 cerrado）中出现的 19 个 Eriosema 分类群中地上和地下器官之间 G 纤维壁的结构和组织化学。根据植物解剖学和组织化学中的标准技术处理样品。G 纤维出现在整个营养体中，并且在具有初级生长的器官中完全是木外的，在具有初期次生生长的器官中是木外和木内的。G-纤维更丰富，在地下器官中具有更厚的G-层。在分析的所有器官中，G-纤维通过有时占据纤维的整个管腔的非木质化内部半透明层（G-层）的存在来识别。Eriosema 植物营养轴中 G 纤维的丰富和广泛存在可能代表了一种适应性机制，并可以解释为什么属于该属的植物能够在不利的 Cerrado 条件下生存。我们认为塞拉多环境的条件可能会刺激这些植物中凝胶状纤维的分化。此外，关于 G 纤维的生态生理学意义，我们强调它们的分类学价值，作为 Eriosema 属的统一特征。Eriosema 植物营养轴中 G 纤维的丰富和广泛存在可能代表了一种适应性机制，并可以解释为什么属于该属的植物能够在不利的 Cerrado 条件下生存。我们认为塞拉多环境的条件可能会刺激这些植物中凝胶状纤维的分化。此外，关于 G 纤维的生态生理学意义，我们强调它们的分类学价值，作为 Eriosema 属的统一特征。Eriosema 植物营养轴中 G 纤维的丰富和广泛存在可能代表了一种适应性机制，并可以解释为什么属于该属的植物能够在不利的 Cerrado 条件下生存。我们认为塞拉多环境的条件可能会刺激这些植物中凝胶状纤维的分化。此外，关于 G 纤维的生态生理学意义，我们强调它们的分类学价值，作为 Eriosema 属的统一特征。