• DOI:10.1007/s11104-015-2703-2
• Corpus ID: 15135734

Impacts of root symbiotic associations on interspecific variation in sugar exudation rates and rhizosphere microbial communities: a comparison among four plant families

@article{Okubo2015ImpactsOR,
  title={Impacts of root symbiotic associations on interspecific variation in sugar exudation rates and rhizosphere microbial communities: a comparison among four plant families},
  author={Atushi Okubo and Motomu Matsusaka and Shuichi Sugiyama},
  journal={Plant and Soil},
  year={2015},
  volume={399},
  pages={345-356}
}

• A. Okubo, Motomu Matsusaka, S. Sugiyama
• Published 1 February 2016
• Environmental Science
• Plant and Soil

Background and aimsSymbiotic associations between rhizobia and arbuscular mycorrhyzal fungi (AMF) influence changes in carbon allocation to plant roots and alter the exudation of signal molecules in their host plants. In this study, we examined the impacts of bacterial and fungal symbiotic associations on the variation in sugar exudation rates from plant roots, and in rhizosphere microbial community structure, by comparing four plant families (e.g., Asteraceae, Brassicaceae, Fabaceae, and Poaceae) with different bacterial and fungal symbiotic associations.Methods and resultsWe determined sugar exudation rates of 23 plant species by regressions of exuded sugars against root mass through periodic samplings of plants grown in pots. Banding patterns from PCR-DGGE analyses of 28 plant species were evaluated by ordination scores relative to their rhizosphere bacterial and fungal community structures. Plant family was the most important source of variation in sugar exudation rates and microbial community structure between plant species. Brassicaceae, which lacks a root symbiotic association, had the lowest sugar exudation rate, the lowest rhizosphere microbial mass, and a distinct fungal community structure relative to the other plant families. Fabaceae had a different bacterial community structure relative to the other plant families.ConclusionsThese results demonstrate that root symbiotic associations have great impacts on the rate of sugar exudation and free-living microbial communities that inhabit the rhizosphere.