【摘要】 植物病原菌在生态系统功能中发挥重要作用。但在全球变化背景下，长期氮沉降如何影响植物病原菌群落尚未得到充分研究。因此，在大兴安岭兴安落叶松林进行了原位氮添加试验，共设置了4个氮添加梯度。2021年7月，采集了土壤、植物根系和叶片样品。利用16SrRNA和18SrRNA测序技术，探讨氮添加对土壤和植物共生病原菌群落的影响及其潜在机制。结果表明：氮添加显著增加了叶片细菌和真菌病原菌多样性，降低了土壤细菌病原菌多样性；氮添加引起根际和根系内生真菌病原菌群落结构发生了显著变化，但未显著改变土壤、根系和叶片细菌病原菌群落结构。冗余分析表明，土壤pH、NO^-₃-N、MBN和MBC是影响土壤和植物细菌和真菌病原菌群落结构的重要环境因子。基于上述，氮添加可能通过改变土壤性质，进而影响土壤和植物病原菌群落结构。更多还原

【Abstract】 Plant pathogens play an important role in ecosystem functions. However, a long-term nitrogen deposition plant pathogen communities have not been fully studied in the context. Therefore, an in situ N addition experiment was conducted in Larix gmelinii forest in Greater Khingan Mountains. Therefore, the soil plant root and leaf samples were collected in July 2021. The effects of nitrogen addition on soil and plant symbiotic pathogen communities and their potential mechanisms were investigated by using 16SrRNA and 18SrRNA sequencing techniques. The results showed that nitrogen addition significantly increased the diversity of bacterial and fungal pathogens in leaves and decreased the diversity of bacterial pathogens. Nitrogen addition caused significant changes in the community structure of endophytic fungal pathogens in rhizosphere and root, but did not significantly change the community structure of bacterial pathogens in soil, root and leaf. Redundancy analysis showed that soil pH, NO^-₃-N, MBN and MBC were important environmental factors affecting soil and plant bacterial and fungal pathogen community structure. Thus nitrogen addition may affect soil and plant pathogen community structure by changing soil properties.更多还原