Endophytic bacterium Bacillus cereus affects host litter decomposition by regulating soil microbial structure and phosphate mineralization

Endophytic bacteria (EB) commonly exist in plants and are recognized to increase plant growth especially under adverse environmental conditions. We here demonstrate that EB Bacillus cereus can accelerate the decomposition of plant litter and enhance nutrient availability for plant growth. First, we obtained plant litter with and without EB inoculation using a model plant Arabidopsis thaliana in a microcosmic experiment. After that we conducted a litter decomposition experiment to investigate the effect of EB on mass loss, phosphorus availability, and soil microbial community composition. We further evaluated wheat (Triticum aestivum) growth using soils amended with either EB-inoculated litter or with litter alone. Inoculation of EB significantly increased the mass loss of A. thaliana litter in the second to fourth month of decomposition, elevated the activity of alkaline phosphatase in the first month of decomposition, and increased soil available phosphorus at the end of decomposition. Illumina MiSeq sequencing and structural equation models also showed that EB inoculation had pronounced impact on the bacterial diversity and composition in soil. Finally, the wheat growth was significantly promoted in the litter with EB decomposition system. EB affected host after life effect likely through accelerating the release of P from plant litter and regulating the composition of soil microorganisms, improving nutrient utilization efficiency in a terrestrial ecosystem. [Display omitted] •The first study to explore the endophytic bacteria regulating its host litter decomposition.•The model plant Arabidopsis thaliana is also a good material for studying the degradation process of litter.•Litter with endophytic bacteria decomposition changed soil microbial structure and litter P release.•Litter with endophytic bacteria decomposition regulated the ‘after-life effect’ of host litter.