不同种植年限对牡丹土壤性状和微生物群落的影响OA

To clarify the effects of different planting years on the soilphysicochemical properties and the bacterial community structure of Paeonia suffruticosa Andr.,this study analyzed soil samples col-lected from varying planting durations(0,3,6,9,and 12 years)and soil depths(0-20 cm,20-40 cm,40-60 cm,and 60-80 cm).Soil physicochemical properties and microbial community structure were systematically analyzed to assess their impacts on peony growth and development.The results indica-ted that soil organic matter(SOM),available potassium(AK),and hydrolytic nitrogen(HN)initially increased and then decreased with increasing planting duration.Specifically,SOM content in the 0-20 cm and 20-40 cm layers peaked in the sixth year before declining significantly(P＜0.05).Microbial community analysis revealed that after six years of planting,the abundance of beneficial bacteria,such as Actinobacteria and Proteobacteria,decreased in the 20-40 cm layer,while the abundance of patho-genic fungi such as Fusarium spp.increased,resulting in bacterial abundance.Correlation analysis demonstrated significant positive relationships between SOM,total nitrogen(TN),total phosphorus(TP),and the phylum Gemmatimonadetes.The cultivar'Fotouqing'exhibited optimal growth vigor during 3-6 years of planting.However,plant height,crown width,new branch length,and other indi-cators significantly decreased after the sixth year(P＜0.05)due to soil microecological imbalance.In conclusion,after six years of continuous planting,the 20-40 cm soil layer exhibited reduced effective-ness,continued reduction in beneficial bacterial,a significant increase in pathogenic fungi,and an over-all soil microecological imbalance,all of which inhibited peony growth and development.This study elucidates the primary causes of growth deterioration in long-term peony cultivation and provides a theoretical basis for sustainable planting management.