Secondary xylem of stem and root of cerrado woody plants: anatomical and functional approach

Abstract

The plant's ability to invest in the wood tissue in different organs is crucial to its survival in terrestrial environments. Wood is a complex system linked to water transport, mechanical support, and storage of essential substances. However, the understanding of wood traits patterns between organs and the relationship between anatomical and functional traits is still limited. In this study, we investigated the anatomical and functional wood patterns between the root and stem across 15 woody species of the Cerrado domain (Brazilian savanna), also exploring the relationships among the wood traits across species. For that, we measured in both organs in all species the anatomical wood traits, theoretical hydraulic conductivity, wood density, and non-structural carbohydrates. Our results revealed a similar wood anatomy, estimation of theoretical hydraulic conductivity, and wood density when compared root and stem, but high content of non-structural carbohydrate in the root. Plant height had a positive effect on wood anatomy when combined ray width with vessel element length and ray density. Wood density was explained by rays and vessels features, while non-structural carbohydrates content was not related to the anatomical traits. We also identified a positive relationship between theoretical hydraulic conductivity and pits size. The wood traits patterns observed provide a more integrated knowledge of wood function, and highlight that storage traits and function are prioritized in Brazilian savanna woody plants.