不同水曲柳褐斑病病级叶片的微生物多样性OACSTPCD

To investigate the microbial diversity and the main pathogenic microorganisms of Fraxinus mandshurica leaves with dif-ferent degrees of brown spot disease,and to analyze the control methods to maintain the ecological safety and enhance the economic benefits of Fraxinus mandshurica plantation forests,leaves infected with brown spot disease to varying degrees at Maoershan Experimen-tal Forest Farm were collected,and the microbial community structure and species composition of Fraxinus mandshurica leaves were de-termined and analyzed using high-throughput sequencing technology.A total of 1 026 fungal operational taxonomic units(OUT)and 322 bacterial OUTs were obtained before and after the disease in the three groups of samples.Among the bacteria,the phyla Proteobac-teria and Actinobacteriota were the dominant phyla;the genera Sphingomonas,Acidibacter and Bradyrhizobium were the main dominant genera.Among the fungi,the phyla Ascomycota and Basidiomycota were the dominant phyla;the genera Vishniacozyma,Septoria,and Hannaella were the dominant genera.There were no significant differences in bacterial diversity and community structure among the three groups of samples,and significant differences in fungal diversity and community structure.It was preliminarily speculated that the Cercospora was a pathogenic bacterium,but its pathogenicity needed further study.