Funding information
The Key Research and Development Program of the Xinjiang Uygur Autonomous Region, Grant/Award number: No. 2022B02003; The Natural Science Foundation of Xinjiang Uygur Autonomous Region, Grant/Award number: 2022D01A193; The National Natural Science Foundation of China, Grant/Award number: No. 31960260.
Abstract: Root system architecture is limited by phylogenetic relationships and ultimately affect the biomass allocation of resource acquisition organs. However, many studies have only focused on the impact of environmental driven trait variation and biomass allocation on root system architecture, neglecting the impact of phylogenetic relationships. Therefore, biomass allocation and phylogenetic relationship affect the root system architecture and its variation patterns were investigated in annual ephemerals. We found that the interspecific variation of root tissue density (RTD) was the highest (51.63%), and the topological index (TI) was the lowest (5.92%). Moreover, the range of intraspecific variation for specific root length (SRL) and specific surface area (SRA) is high, and the TI is low. This convergence and divergence of root traits reflect the Phenotypic plasticity of roots and their adaptation to environmental filtering and interspecific competition. Maximum root depth (MRD) was detected significantly and weakly phylogenetic signal (0<K<1, P<0.05). The leaf mass fraction (LMF), which is significantly positively correlated with MRD, SRA, and SRL, reflects the water demand of plants. Meanwhile, the root mass fraction (RMF), which is significantly positively correlated with MRD, is the foundation for exploring soil spatial roots. These correlations are influenced by phylogenetic relationships. Although biomass allocation indicators and trait variation indicators can reflect the adaptive strategies of annual ephemerals, the impact of phylogenetic relationships is equally important.
Key word: Interspecific variation; Intraspecific variation; Root mass fraction; Leaf mass fraction;