Relationships between root exudation and root morphological and architectural traits vary with growing season

作者：Yuqiu Gao, Huimin Wang, Fengting Yang, Xiaoqin Dai, Shengwang Meng, Mingyuan Hu, Liang Kou, Xiaoli Fu · 发表于：Tree Physiology · 年份：2023 · DOI：10.1093/treephys/tpad118 · 被引用次数：52 · 研究领域：Plant nutrient uptake and metabolism、Legume Nitrogen Fixing Symbiosis、Agronomic Practices and Intercropping Systems

Plants allocate a substantial amount of C belowground for root exudates and for the construction and adjustment of root morphological and architectural traits. What relationships exist between root exudates and other root traits and these relationships change with growing season, however, remain unclear. We quantified the root exudation rate and root morphological traits, including total root length (RL), total root surface area (RS), root diameter (RD), specific root length (SRL), specific root area (SRA) and root tissue density (RTD), and architectural traits, such as branching intensity (BI), and investigated their associations during the rapidly growing season (April and August) and the slowly growing season (December) of three common native tree species, Liquidambar formosana, Michelia maudiae and Schima superba, in subtropical China. We found that the linkages of RD, SRL, SRA, RTD and BI did not change with the growing season, reflecting their highly conservative relationships. The root exudation rate varied significantly with growing season (P < 0.05) and produced various associations with other root traits at different growing seasons. During the rapidly growing season (i.e., April), the exudation rate was the highest and was positively correlated with RL. The exudation rate was the lowest during the slowly growing season (i.e., December) and was negatively associated with RL, RS and RTD. Our findings demonstrate the seasonality of the linkages of root exudation rate ...