羊肚菌连作对沙质土壤微生物及代谢物的影响OA

Continuous cropping remains a major bottleneck for the sustainable cultivation of morel mushrooms(Morchella spp.),yet the mechanisms driving yield decline in sandy soils are poorly understood.To address this,we examined how repeated cropping of Morchella sextelata in sandy soil affects the physicochemical environment,microbial communities,and metabolite profiles in the stipe base zone,and how these factors interact.The results showed that compared with non-continuous cropping,continuous cropping resulted in significantly increases in nitrate nitrogen,ammonium nitrogen,available phosphorus,and organic carbon,while soil pH decreased.At the microbial level,the relative abundance of Fusarium and Mortierella rose in continuous cropping soil,whereas the phyla Pseudomonadota and Bacteroidota were significantly decreased.Metabolomic profiling identified 349 upregulated differential metabolites,predominantly organic acids and derivatives,organic heterocyclic compounds,and benzenoid aromatic compounds.Among them,7-oxo-8,15-isopimaradien-1 8-oic acid showed a significant negative correlation with Morchella abundance(P＜0.05)and a highly significant positive correlation with Fusarium(P＜0.01).These findings provide mechanistic insights to the continuous cropping problem in sandy soil-based morel cultivation and offer a foundation for developing targeted mitigation strategies.