Data_Sheet_1_Plant Identity Shaped Rhizospheric Microbial Communities More Strongly Than Bacterial Bioaugmentation in Petroleum Hydrocarbon-Polluted Sediments.docx

Manipulating the plant-root microbiota has the potential to reduce plant stress and promote their growth and production in harsh conditions. Community composition and activity of plant-roots microbiota can be either beneficial or deleterious to plant health. Shifting this equilibrium could then strongly affect plant productivity in anthropized areas. In this study, we tested whether repeated bioaugmentation with Proteobacteria influenced plant productivity and the microbial communities associated with the rhizosphere of four plant species growing in sediments contaminated with petroleum hydrocarbons (PHCs). A mesocosm experiment was performed in randomized block design with two factors: (1) presence or absence of four plants species collected from a sedimentation basin of a former petrochemical plant, and (2) bioaugmentation or not with a bacterial consortium composed of ten isolates of Proteobacteria. Plants were grown in a greenhouse over 4 months. MiSeq amplicon sequencing, targeting the bacterial 16S rRNA gene and the fungal ITS, was used to assess microbial community structures of sediments from planted or unplanted microcosms. Our results showed that while bioaugmentation caused a significant shift in microbial communities, presence of plant and their species identity had a stronger influence on the structure of the microbiome in PHCs contaminated sediments. The outcome of this study provides knowledge on the diversity and behavior of rhizosphere microbes associated with indigenous plants following repeated bioaugmentation, underlining the importance of plant selection in order to facilitate their efficient management, in order to accelerate processes of land reclamation.

调节植物根际微生物群落具有减轻植物压力、促进其在恶劣条件下生长与产出的潜力。植物根际微生物群落的组成与活性可能对植物健康产生益或害的影响。调整这一平衡可能对人类活动区域内的植物生产力产生显著影响。在本研究中，我们检验了反复生物增菌添加的变形菌对植物生产力及其与四种植物物种根际相关的微生物群落有何影响。实验采用随机区组设计，包含两个因素：(1)是否包含从前石化厂沉淀池中收集的四种植物物种，以及(2)是否使用由十个变形菌分离株组成的细菌联合体进行生物增菌。植物在温室中生长了四个月。采用MiSeq扩增子测序技术，针对细菌16S rRNA基因和真菌ITS，对种植或未种植微宇宙的沉积物微生物群落结构进行评估。我们的结果表明，尽管生物增菌导致了微生物群落的显著转变，但植物的存在及其物种身份对受石油烃（PHCs）污染的沉积物中微生物群落的结构具有更强的影响。本研究的结果为了解经过反复生物增菌后，与本土植物相关的根际微生物的多样性和行为提供了知识，强调了植物选择在促进其高效管理、加速土地复垦进程中的重要性。