呼伦贝尔沙地樟子松林土壤和根内真菌泛化种和特化种结构与功能特征

[Objective]To elucidate the structural and functional characteristics of the fungal community of generalized and specialized species in the soil and roots of Pinus sylvestris var.mongolia and their correlation with soil physical and chemicalproperties.[Method]This study took Pinus sylvestris var.mongolia natural and plantation forests(middle-aged,near-mature and mature forests)in Hulunbuir Desert as the research object,the Illumina MiSeq high-throughput sequencing and FUNGuild platform were used to identify and analyse the fungal generalized and specialised species communities in Pinus sylvestris soils and roots.[Result](1)A total of 169 OTUs were retained in the soil and intra-root fungal species,belonging to 111 species belonging to 5 phyla,12 classes,29 orders,58 families,64 genera,among which the dominant genera were Tricholoma,Suillus,Inocybe and Cadophora.A total of 603 OTUs were retain ed,belonging to 8 phyla,25 classes,58 orders,107 families,165 genera and 315 species,and 216 OTUs were retained in the root fungal species,belonging to 4 phyla,13 classes,35 orders,59 families,69 genera and 110 species,and the dominant genera of the specialized species were Penicillium,Geminibasidium and Acephala,Inocybe,respectively.(2)Among soil and intra-root fungi,the relative abundance of saprotrophic fungi was significantly higher(P＜0.05)in the specialized species than in the generalized species;in addition to this,the relative abundance of saprotrophic and pathotrophic fungi was significantly(P＜0.05)higher(P＜0.05)in the soil fungi specialized species than in the intra-root fungi specialized species.(3)Soil and root fungi generalized species of symbiotic nutritive fungi accounted for the highest proportion of 8.32％to 51.42％,and the dominant ecological function group was exophytic mycorrhizal fungi;soil fungi specialization species of saprophytic nutritive fungi accounted for the highest proportion of 17.01％to 40.01％;and the specialization species of intra-root fungi accounted for the highest proportion of symbiotic nutritive fungi of 43.87％to 54.45％,and the dominant ecological function group was exophytic mycorrhizal Fungi.(4)Soil and roots fungal community structure was primarily driven by Soil Organic Matter,Active Nitrogen,Total Nitrogen and Total Potassium,and was significantly and positively correlated with generalized and specialized species communities.[Conclusion]Fungal generalized and specialized species in Pinus sylvestris Desert forests had different community structures,and the community structures of fungal specialized species in soil and roots varied significantly.During the growth process of Pinus sylvestris var.mongolia,a large number of symbiotic nutritive fungi of generalized species dominated,which was conducive to the rapid growth of forest trees;and putrefactive nutritive fungi of speciali zed species played a dominant role,which was conducive to the improvement of the resistance ability of forest trees to the external environment.The communities of generalized and specialized species of fung I were affected by changes in soil physical and chemical properties,in which Soil Organic Carbon,Available Nitrogen,Total Nitrogen and Total Potassium were the main driving factors for changes in the structure of fungal communities.The results of the study can help to deeply understand the ecological functions of soil and intra-root fungi in Pinus sylvestris var.mongolia forests,providing a scientific basis for the sustainable management and protection of Pinus sylvestris var.mongolia.forests,and ensuring the dual realisation of their ecological health and economic benefits.