Aims

Specific soil bacteria can sense and respond to the selective rhizosphere recruitment of root exudates using unique systems of chemotaxis that mediate plant-microbe and microbe-microbe interactions. This study investigates how the bacterial chemotaxis systems have been impacted by selection during the domestication of rice (Oryza species).

Methods

Shotgun metagenomic sequencing and 16S rRNA gene amplicon sequencing were performed to investigate the bacterial chemotaxis systems and chemotactic bacteria in the rhizospheres of wild and cultivated rice. Metabolomics analysis was performed to examine the root metabolites of different accessions of rice.

Results

The bacterial chemotaxis genes exhibited a higher abundance in the rhizospheres of wild rice than cultivated rice, and that the compositional profile of chemotaxis genes was distinctly different between types of rice. Differential selection of chemotaxis systems was at least partially driven by changes in the metabolite profiles of rice roots that were affected by domestication. A core group of chemotactic bacteria was also identified, and specific chemotactic bacteria were found to function as hub taxa in the rhizosphere bacterial community.

Conclusion

The present study provides novel insights into the composition and function of the bacterial chemotaxis systems in the rhizospheres of wild and domesticated rice. It also provides a new perspective on the impact of rice domestication on the assembly of rhizomicrobiome.

中文翻译：

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水稻驯化影响根际细菌趋化系统的组成和功能

宗旨

特定的土壤细菌可以使用介导植物-微生物和微生物-微生物相互作用的独特趋化系统来感知和响应根系分泌物的选择性根际募集。本研究调查了水稻（Oryza种）驯化过程中选择如何影响细菌趋化系统。

方法

进行鸟枪宏基因组测序和16S rRNA基因扩增子测序以研究野生和栽培水稻根际中的细菌趋化系统和趋化细菌。进行代谢组学分析以检查不同水稻种质的根代谢物。

结果

细菌趋化基因在野生稻的根际表现出比栽培稻更高的丰度，并且趋化基因的组成谱在不同类型的水稻之间存在明显差异。趋化系统的差异选择至少部分是由受驯化影响的水稻根部代谢物谱的变化驱动的。还鉴定了一组核心趋化细菌，并发现特定的趋化细菌在根际细菌群落中起到枢纽分类群的作用。

结论

本研究为野生和驯化水稻根际细菌趋化系统的组成和功能提供了新的见解。它还为水稻驯化对根际微生物组组装的影响提供了新的视角。