羊肚菌栽培对沙漠砂基质中微生物群落及基质理化性质的影响

Impacts of Morel Cultivation on the Microbial Community and Physiochemical Characteristics in a Substratum of Desert Sand

为开发沙漠砂代替土壤作为羊肚菌栽培基质,研究羊肚菌栽培对沙漠砂中微生物群落及基质理化性质的影响。利用扩增子测序分别检测栽培与未栽培羊肚菌的沙漠砂中细菌、真菌群落,解析总有机碳、腐殖质和氮素含量等理化性质。收获子实体产量(1210±259)g/m^(2)鲜重,说明沙漠砂栽培羊肚菌可行。沙漠砂基质中微生物多样性在羊肚菌栽培过程中短暂下降,在羊肚菌出菇采收后回升。真菌群落以子囊菌门为主。随着羊肚菌在沙漠砂中增殖,扫描电镜观察到大量菌丝形成网络状缠绕固定沙漠砂颗粒。细菌群落以变形菌门、放线菌门、拟杆菌门为主。假单胞菌属相对丰度在羊肚菌菌丝生长期明显上升,蓝细菌门在羊肚菌采收后大幅度扩增,伴随总氮和铵态氮含量显著上升,超越了栽培羊肚菌之前的初始水平。栽培羊肚菌使沙漠砂中有机质含量提升7倍,出菇后基质中胡敏酸、富啡酸、胡敏素含量显著上升。研究结果揭示了用沙漠砂种植羊肚菌在收获高值农产品的同时改良沙漠砂理化性质的应用潜力。

In order to utilize desert sand replacing soil as a substrate for morel cultivation,this study is aimed to dissect the impacts of morel cultivation on the microbial community and physiochemical characteristics of the desert sand substrate.Metabarcoding was adopted to track the composition and diversity of bacterial and fungal communities in the desert sand with or without morel cultivation.Physiochemical characteristics such as total organic carbon,humic substances,and nitrogen content were measured.The harvested morel yield was(1210±259)g/m^(2) fresh weight,indicating that cultivating morel in desert sand is feasible.The microbial diversity in the desert sand substratum decreased temporarily during the cultivation of the morel,and increased again after the morels were harvested.The fungal communities were dominated by Ascomycota.As the morel proliferated in the desert sand,a large number of hyphae that formed a network entangling and fixing desert-sand particles were observed by scanning electron microscopy.The bacterial communities were dominated by Proteobacteria,Actinobacteria,and Bacteroides.The relative abundance of Pseudomonas increased significantly during the growth period of morel mycelium.Cyanobacteria expanded significantly after the harvest,accompanied by a significant increase in the contents of total nitrogen and ammonium nitrogen,that surpassed the initial levels before morel sowing.Morel cultivation increased the organic matter content in the desert sand substrate by 7 times.The contents of humic acid,fulvic acid,and humin in the substrate increased significantly after morel fruiting and harvest.The results demonstrate the application potential of cultivating morel in desert sand to harvest high-value agricultural products while improving the physiochemical properties of the desert sand.