Background : Plant microbiome plays an important role in promoting plant health and production. However, even though the microbiomes in various compartments have been widely investigated, the association across plant compartments from soil to leaf remain unclear. Tea is a globally popular beverage due to its flavor and health benefits associating with secondary metabolites; the microbiomes of tea plant ( Camellia sinensis ) play a significant role in the production of these secondary metabolites. Here, we sequenced the microbiomes of bulk and rhizosphere soils, roots and leaves of C. sinensis collected from tea plantations across over 2000 km to investigate the association and driving mechanisms for microbiomes in the compartments.
Results : Camellia sinensis microbiomes differed between the compartments with α-diversity gradually decreasing from soils to roots and leaves. The core leaf microbiome comprised Bacilli, Sphingobacteriia and α-Proteobacteria, which we suggest might ascendingly migrate from soils to leaves. Microbial community assembly processes were dominated by deterministic processes in bulk and rhizosphere soils; these assembly processes were dominated by stochastic processes in roots and leaves. Dispersal limitation was stronger in old leaves than in other compartments. Amino acids were also critical drivers for environmental selection. The microbiomes in C. sinensis roots and leaves possessed a lower intensity of microbial associations and more negative microbial associations than in bulk and rhizosphere soils, suggesting that the contribution of microbial interactions varied in different compartments.
Conclusion : In summary, there is a trade-off between stochastic and deterministic processes in microbiomes community assembly along from soil to leaf of C. sinensis . These results provide valuable information for understanding the associations and driving mechanism of microbiomes in various C. sinensis compartments, which could be used to predict C. sinensis microbiome and harness its power to improve tea production and quality.