Liu Jiaying, Zhang Weixi, Liu Yuting, Zhu Wenxu, Yuan Zhengsai, Su Xiaohua, Ding Changjun
College of Forestry, Shenyang Agriculture University, Shenyang, China.
State Key Laboratory of Tree Genetics and Breeding, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, China.
Front Plant Sci. 2023 Mar 30;14:1143878. doi: 10.3389/fpls.2023.1143878. eCollection 2023.
The above-ground parts of terrestrial plants are collectively known as the phyllosphere. The surface of the leaf blade is a unique and extensive habitat for microbial communities. Phyllosphere bacteria are the second most closely associated microbial group with plants after fungi and viruses, and are the most abundant, occupying a dominant position in the phyllosphere microbial community. Host species are a major factor influencing the community diversity and structure of phyllosphere microorganisms.
In this study, six Populus spp. were selected for study under the same site conditions and their phyllosphere bacterial community DNA fragments were paired-end sequenced using 16S ribosomal RNA (rRNA) gene amplicon sequencing. Based on the distribution of the amplicon sequence variants (ASVs), we assessed the alpha-diversity level of each sample and further measured the differences in species abundance composition among the samples, and predicted the metabolic function of the community based on the gene sequencing results.
The results revealed that different Populus spp. under the same stand conditions resulted in different phyllosphere bacterial communities. The bacterial community structure was mainly affected by the carbon and soluble sugar content of the leaves, and the leaf nitrogen, phosphorus and carbon/nitrogen were the main factors affecting the relative abundance of phyllosphere bacteria.
Previous studies have shown that a large proportion of the variation in the composition of phyllosphere microbial communities was explained by the hosts themselves. In contrast, leaf-borne nutrients were an available resource for bacteria living on the leaf surface, thus influencing the community structure of phyllosphere bacteria. These were similar to the conclusions obtained in this study. This study provides theoretical support for the study of the composition and structure of phyllosphere bacterial communities in woody plants and the factors influencing them.
陆生植物的地上部分统称为叶际。叶片表面是微生物群落独特而广阔的栖息地。叶际细菌是仅次于真菌和病毒的与植物关系第二密切的微生物类群，且数量最为丰富，在叶际微生物群落中占据主导地位。宿主物种是影响叶际微生物群落多样性和结构的主要因素。
本研究在相同立地条件下选取6个杨树品种进行研究，采用16S核糖体RNA（rRNA）基因扩增子测序对其叶际细菌群落DNA片段进行双端测序。基于扩增子序列变体（ASV）的分布，我们评估了每个样本的α多样性水平，进一步测定了样本间物种丰度组成的差异，并根据基因测序结果预测了群落的代谢功能。
结果表明，相同林分条件下不同杨树品种导致叶际细菌群落不同。细菌群落结构主要受叶片碳和可溶性糖含量影响，叶片氮、磷和碳氮比是影响叶际细菌相对丰度的主要因素。
先前的研究表明，叶际微生物群落组成的很大一部分变异是由宿主自身解释的。相比之下，叶片携带的养分是生活在叶片表面细菌的可用资源，从而影响叶际细菌的群落结构。这些与本研究得出的结论相似。本研究为木本植物叶际细菌群落的组成和结构及其影响因素的研究提供了理论支持。
