Abstract: [Objective] This study was investigated endophytic fungi diversity,infection rate,infection structure,and host mineral nutrient content to understond the effects of endophytic fungi colonization on the mineral nutrition of V. uliginosum.[Method] This study was conducted in the Daxing'an Mountains area with three soil types:Mountain land type, Meadow bog permafrost soil layer type, Meadow bog with soil layer type. The diversity of root mycorrhizal fungi of V. uliginosum was analyzed by modern biological techniques (ITS). Multivariate statistical analysis was used to study the relationship between mycorrhizal colonization and host plant mineral nutrition.[Result] 1) The diversity of endophytic fungi (H'=3.58~4.36) and infection structure (exogenous mycelium, intracellular hyphae with partition, intracellular nonseptate hyphae group, intracellular hyphae, missing of the epidermal cells) were rich, the infection rate was high (54.98%~68.09%) on V. uliginosum roots in the Greater Xing'an Mountains. The endophytic fungi in the root system of V. uliginosum in different site types had the specificity. Among them, the mountain land type and the meadow bog with soil layer type were dominated by Phialocephala, while the dominant species of the meadow bog permafrost soil layer type was Meliniomyces. 2) Among the three site types, the endophytic fungi diversity and infection rate were the highest in the meadow bog permafrost soil layer type, followed by the mountain land type, and the meadow bog with soil layer type was lowest. The content of most mineral elements in the three site types showed the same trend as that root endophytic fungi diversity and infection rate, with the exception of Zn element in V. uliginosum. 3) The endophytic fungi infection rate was significantly or extremely significantly positively correlated with N, P, K, Ca and Fe content, but had an extremely negative correlation with Zn content (r=-0.944^**).[Conclusion] The endophytic fungi can significantly promote the mineral nutrient accumulation of V. uliginosum, suggesting that the endophytic fungi colonization is an important factor affecting the mineral nutrient status of V. uliginosum, and the environmental conditions was important factor influencing the diversity and abundance of endophytic fungi in V. uliginosum roots.

Key words: Vaccinium uliginosum, endophytic fungi, diversity, colonization status, mineral nutrient