Majeed Aqsa, Liu Jinbao, Knight Adelle J, Pajerowska-Mukhtar Karolina M, Mukhtar M Shahid
Department of Biology, University of Alabama at Birmingham, 3100 East Science Hall, 902 14th Street South, Birmingham, AL 35294, USA.
Department of Genetics & Biochemistry, Biosystems Research Complex, Clemson University, 105 Collings St., Clemson, SC 29634, USA.
Microorganisms. 2024 Aug 6;12(8):1595. doi: 10.3390/microorganisms12081595.
Salt marshes are highly dynamic and biologically diverse ecosystems that serve as natural habitats for numerous salt-tolerant plants (halophytes). We investigated the bacterial communities associated with the roots and leaves of plants growing in the coastal salt marshes of the Bayfront Beach, located in Mobile, Alabama, United States. We compared external (epiphytic) and internal (endophytic) communities of both leaf and root plant organs. Using 16S rDNA amplicon sequencing methods, we identified 10 bacterial phyla and 59 different amplicon sequence variants (ASVs) at the genus level. Bacterial strains belonging to the phyla , , and were highly abundant in both leaf and root samples. At the genus level, sequences of the genus were common across all four sample types, with the highest abundance found in the leaf endophytic community. Additionally, was found to be dominant in leaf tissue compared to roots. Our study revealed that plant habitat (internal vs. external for leaves and roots) was a determinant of the bacterial community structure. Co-occurrence network analyses enabled us to discern the intricate characteristics of bacterial taxa. Our network analysis revealed varied levels of ASV complexity in the epiphytic networks of roots and leaves compared to the endophytic networks. Overall, this study advances our understanding of the intricate composition of the bacterial microbiota in habitats (epiphytic and endophytic) and organs (leaf and root) of coastal salt marsh plants and suggests that plants might recruit habitat- and organ-specific bacteria to enhance their tolerance to salt stress.
盐沼是高度动态且生物多样的生态系统，为众多耐盐植物（盐生植物）提供自然栖息地。我们调查了生长在美国阿拉巴马州莫比尔湾滨海滩涂沿海盐沼中的植物根和叶相关的细菌群落。我们比较了植物叶和根器官的外部（附生）和内部（内生）群落。使用16S rDNA扩增子测序方法，我们在属水平上鉴定出10个细菌门和59个不同的扩增子序列变体（ASV）。属于 、 和 门的细菌菌株在叶和根样本中都高度丰富。在属水平上， 属的序列在所有四种样本类型中都很常见，在叶内生群落中丰度最高。此外，与根相比， 被发现是叶组织中的优势菌。我们的研究表明，植物栖息地（叶和根的内部与外部）是细菌群落结构的一个决定因素。共现网络分析使我们能够辨别细菌分类群的复杂特征。我们的网络分析显示，与内生网络相比，根和叶的附生网络中ASV复杂性水平不同。总体而言，这项研究推进了我们对沿海盐沼植物栖息地（附生和内生）和器官（叶和根）中细菌微生物群复杂组成的理解，并表明植物可能招募栖息地和器官特异性细菌以增强其对盐胁迫的耐受性。
