Alkaline soil pH affects bulk soil, rhizosphere and root endosphere microbiomes of plants growing in a Sandhills ecosystem

• Published in: FEMS microbiology ecology Vol. 97; no. 4; p. 1
• Main Authors: Lopes, Lucas Dantas, Hao, Jingjie, Schachtman, Daniel P
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01-04-2021
• Subjects: Alkaline soils; Bacteria - genetics; Cation exchange; Cation exchanging; Chemical properties; Ecology; Flowers & plants; Hydrogen-Ion Concentration; Microbial activity; Microbiology; Microbiomes; Microbiota; Microorganisms; Northern Hemisphere; Observations; pH effects; Plant extracts; Plant Roots; Plant species; Rhizosphere; RNA, Ribosomal, 16S - genetics; rRNA 16S; Soil; Soil chemistry; Soil investigations; Soil Microbiology; Soil pH; Soil stresses; Soils; United States; soil ecology; root-associated microbes; alkaline soils; plant selection; endophytic bacteria; rhizosphere microbiome
• ISSN: 0168-6496; 1574-6941
• DOI: 10.1093/femsec/fiab028

ABSTRACT
Soil pH is a major factor shaping bulk soil microbial communities. However, it is unclear whether the belowground microbial habitats shaped by plants (e.g. rhizosphere and root endosphere) are also affected by soil pH. We investigated this question by comparing the microbial communities associated with plants growing in neutral and strongly alkaline soils in the Sandhills, which is the largest sand dune complex in the northern hemisphere. Bulk soil, rhizosphere and root endosphere DNA were extracted from multiple plant species and analyzed using 16S rRNA amplicon sequencing. Results showed that rhizosphere, root endosphere and bulk soil microbiomes were different in the contrasting soil pH ranges. The strongest impact of plant species on the belowground microbiomes was in alkaline soils, suggesting a greater selective effect under alkali stress. Evaluation of soil chemical components showed that in addition to soil pH, cation exchange capacity also had a strong impact on shaping bulk soil microbial communities. This study extends our knowledge regarding the importance of pH to microbial ecology showing that root endosphere and rhizosphere microbial communities were also influenced by this soil component, and highlights the important role that plants play particularly in shaping the belowground microbiomes in alkaline soils.
Soil pH affects root-associated microbiomes.