镉污染区与非污染区苏柳种子内生菌群落特征比较OA

Soil cadmium pollution is a global environmental issue that seriously threatens ecosystem security.As an important component of the host microbiome,plant endophytes play a key role in plant adaptation to heavy metal stress.However,the effects of soil cadmium pollution on the seed endophytic microbiome of for-est trees remained unclear.To elucidate the impact of soil cadmium pollution on the seed endophytic microbi-ome of woody plants,Suliu1704(Salix × jiangsuensis,J1704)was used as the experimental material,and Illumina high-throughput sequencing technology was employed to analyze the community structure of seed endophytic bacteria and fungi from cadmium-polluted and unpolluted areas.The results showed that in the bacterial community,the number of OTUs in the cadmium-polluted area(1 137-1 239)was significantly higher than that in the unpolluted area(336-381).The abundances of Proteobacteria and Actinobacteriota increased markedly,while the abundance of Firmicutes decreased.The fungal community composition was relatively conservative,with Ascomycota being absolutely dominant.Alpha diversity analysis revealed that bacterial diversity indices such as Sobs,Chao1,and ACE were significantly higher in the cadmium-polluted area,whereas fungal diversity showed no significant changes.PCoA and PERMANOVA analyses indicated that the differences in bacterial community structure between the two groups were relatively small,and the differences in fungal communities were also not significant.LEfSe analysis identified differential biomarker taxa:in bacteria,Firmicutes was enriched in the unpolluted area,while Proteobacteria and Actinobacteriota were enriched in the cadmium-polluted area;in fungi,Pleosporales and Didymellaceae were enriched in the unpolluted area,whereas Basidiomycota,Leotiomycetes,and Helotiales were enriched in the cadmium-pollu-ted area.PICRUSt2 functional prediction showed that the main metabolic functional compositions of bacteria and fungi were similar between the two groups,but the abundance of fungal metabolic pathways was general-ly reduced in the cadmium-polluted area.