Spatial dynamics of dark septate endophytes and soil factors in the rhizosphere of Ammopiptanthus mongolicus in Inner Mongolia, China

Improved understanding of the spatial patterns of desert soil resources and the role of dark septate endophytes (DSE) is required to measure plant growth in desert areas. Spatial dynamics of DSE and soil factors were investigated in Wuhai, Urad Back Banner and Alxa Left Banner, located in Inner Mongolia, China. Soil samples in the rhizosphere of Ammopiptanthus mongolicus were collected. Sampling sites and soil depth had a significant influence on the morphology, distribution and infection of DSE. Hyphae, microsclerotia and total root infection of DSE reached their maxima in the 0-20 cm soil layer. Microsclerotial infection at Wuhai and Alxa Left Banner was higher than that at Urad Back Banner. Hyphal infection was significantly positively correlated with amounts of organic matter and available nitrogen, and activities of soil alkaline phosphatase, acid phosphatase and urease. Microsclerotial infection was significantly positively correlated with amounts of soil organic matter and available nitrogen. Root infection had no significant correlation with soil factors. We concluded that the dynamics of DSE have a highly spatial pattern, and were influenced by nutrient availability and enzymatic activity. This study suggests that the morphology and infection of DSE are useful indicators for evaluating soil quality and function of desert ecosystems.