Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Xueyuan Road, Haikou City, Hainan Province, 571101, China.
Hainan Danzhou Tropical Agro-ecosystem National Observation and Research Station, Danzhou City, Hainan Province, 571737, China.
Commun Biol. 2024 Sep 27;7(1):1192. doi: 10.1038/s42003-024-06907-x.
Phyllosphere microorganisms execute important ecological functions including supporting host plant growth, enhancing host resistance to abiotic stresses, and promoting plant diversity. How leaf developmental stages affect plant-microbiome interactions and phyllosphere microbial community assembly and diversity is poorly understood. In this study, we utilized amplicon sequencing of 16S rRNA and ITS genes to investigate the composition and diversity of microbial communities across different leaf developmental stages of rubber trees. Our findings reveal that endophytic microbial communities, particularly bacterial communities, are more influenced by leaf senescence than by epiphytic communities. The high abundance of metabolism genes in the endosphere of yellow leaves contributes to the degradation and nutrient relocation processes. Nutrient loss leads to a higher abundance of α-Proteobacteria (r-selected microorganisms) in the yellow leaf endosphere, thereby promoting stochastic community assembly. As leaves age, the proportion of microorganisms entering the inner layer of leaves increases, consequently enhancing the diversity of microorganisms in the inner layer of leaves. These results offer insights into the mechanisms governing community assembly and diversity of leaf bacteria and fungi, thereby advancing our understanding of the evolving functions of microbial communities during leaf senescence in general, and for an important tropical crop species in particular.
叶际微生物执行着重要的生态功能，包括支持宿主植物生长、增强宿主对非生物胁迫的抗性，以及促进植物多样性。然而，叶片发育阶段如何影响植物-微生物组相互作用以及叶际微生物群落的组装和多样性，目前仍知之甚少。在这项研究中，我们利用 16S rRNA 和 ITS 基因的扩增子测序技术，研究了橡胶树不同叶片发育阶段的微生物群落组成和多样性。研究结果表明，与叶表微生物群落相比，内生微生物群落，特别是细菌群落，受叶片衰老的影响更大。黄叶内生体中丰富的代谢基因有助于降解和养分再定位过程。养分的流失导致黄叶内生体中α-变形菌（r-选择微生物）的丰度更高，从而促进了随机群落组装。随着叶片的衰老，进入叶片内层的微生物比例增加，进而增加了叶片内层微生物的多样性。这些结果深入了解了控制叶片细菌和真菌群落组装和多样性的机制，从而增进了我们对微生物群落在叶片衰老过程中不断变化的功能的理解，特别是对重要的热带作物物种。
