Phyllostachys edulis (moso bamboo) ages significantly affect soil nitrogen transformation and endophytic microbes but niche differentiations outweigh ages in shaping microbial communities of moso bamboo-soil system

Abstract Background: Phyllostachys edulis (moso bamboo) is a key source of non-wood forest products. Clarifying the linkage among bamboo growth, soil nutrient and core microbe can expand the horizon on nutrient management practices and functional endophytic and rhizospheric microbes.Results: In this study, young (0.5-yr), mature (2.5-yr and 4.5-yr) and old (6.5-yr) bamboo plants were selected in a moso bamboo field, and above-ground tissues, below-ground roots (rhizomes) and rhizospheric soils were sampled. The bamboo biomass, soil properties and endophytic microbes were determined and quantify their comprehensive relationships. Bamboo ages had negligible impacts on the bamboo height, diameter at breast height and above-ground biomass. Organic matter and nitrogen (N) contents in the rhizospheric soil of the 0.5-yr bamboo were significantly higher than those of the other three age groups. The rhizospheric soil of the 6.5-yr bamboo had the lowest N mineralization rate and urease activity. Significant differences in bacterial and fungal communities were found in the above-ground tissues but not in the rhizospheric soils associated with plants of different ages. Bacterial and fungal community structures in the above-ground tissues were significantly different from their counterparts in the rhizospheric soils. Conclusions: Bamboo ages significantly affected N transformation rates, functional gene abundances and urease activities of rhizospheric soils and endophytic bacterial community structures. However, niche differentiations outweighed ages in shaping the whole microbial communities of bamboo aboveground tissues, roots and rhizospheric soils. In the future, moso bamboo management should consider balanced applications of ammonium-N and other nutrients and utilisations of Chytridiomycota to stimulate moso bamboo growth.