Yuan Zuoqiang, Ye Ji, Lin Fei, Wang Xing, Yang Teng, Bi Boyuan, Mao Zikun, Fang Shuai, Wang Xugao, Hao Zhanqing, Ali Arshad
Shaanxi Key Laboratory of Qinling Ecological Intelligent Monitoring and Protection, School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China.
CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
Plants (Basel). 2023 Nov 15;12(22):3854. doi: 10.3390/plants12223854.
As a vital component of biodiversity, phyllosphere bacteria in forest canopy play a critical role in maintaining plant health and influencing the global biogeochemical cycle. There is limited research on the community structure of phyllosphere bacteria in natural forests, which creates a gap in our understanding of whether and/or how phyllosphere bacteria are connected to leaf traits of their host. In this study, we investigated the bacterial diversity and composition of the canopy leaves of six dominant tree species in deciduous broad-leaved forests in northeastern China, using high-throughput sequencing. We then compare the differences in phyllosphere bacterial community structure and functional genes of dominant tree species. Fourteen key leaf functional traits of their host trees were also measured according to standard protocols to investigate the relationships between bacterial community composition and leaf functional traits. Our result suggested that tree species with closer evolutionary distances had similar phyllosphere microbial alpha diversity. The dominant phyla of phyllosphere bacteria were Proteobacteria, Actinobacteria, and Firmicutes. For these six tree species, the functional genes of phyllosphere bacteria were mainly involved in amino acid metabolism and carbohydrate metabolism processes. The redundancy and envfit analysis results showed that the functional traits relating to plant nutrient acquisition and resistance to diseases and pests (such as leaf area, isotope carbon content, and copper content) were the main factors influencing the community structure of phyllosphere bacteria. This study highlights the key role of plant interspecific genetic relationships and plant attributes in shaping phyllosphere bacterial diversity.
作为生物多样性的重要组成部分，森林冠层中的叶际细菌在维持植物健康和影响全球生物地球化学循环方面发挥着关键作用。目前对天然森林中叶际细菌群落结构的研究有限，这使得我们在理解叶际细菌是否以及如何与宿主的叶片性状相关联方面存在空白。在本研究中，我们利用高通量测序技术调查了中国东北落叶阔叶林六种优势树种冠层叶片的细菌多样性和组成。然后，我们比较了优势树种叶际细菌群落结构和功能基因的差异。还根据标准方案测量了其宿主树木的14个关键叶片功能性状，以研究细菌群落组成与叶片功能性状之间的关系。我们的结果表明，进化距离较近的树种具有相似的叶际微生物α多样性。叶际细菌的优势门类为变形菌门、放线菌门和厚壁菌门。对于这六种树种，叶际细菌的功能基因主要参与氨基酸代谢和碳水化合物代谢过程。冗余分析和envfit分析结果表明，与植物养分获取以及对病虫害抗性相关的功能性状（如叶面积、同位素碳含量和铜含量）是影响叶际细菌群落结构的主要因素。本研究突出了植物种间遗传关系和植物属性在塑造叶际细菌多样性方面的关键作用。
