Crop types and irrigation regimes as drivers of plastisphere bacterial communities in plastic-mulching croplands of subtropical China

The plastisphere microbiome is intimately linked to the fate and persistence of plastic debris, as well as soil health and food safety. However, the dominant drivers and pathways shaping plastisphere bacterial communities remain largely unknown. Here, soil and plastic residues were sampled from 75 plastic-mulching croplands in subtropical China as part of a nationwide long-term monitoring effort to characterize the effects of system management practices and plastic debris features on plastisphere bacterial communities. The plastisphere communities of the croplands were primarily shaped by crop types, irrigation regimes, and plastic debris abundances. The plastisphere bacterial communities of soil systems with vegetable/tobacco planting, trickle irrigation, and plastic levels of 100–300 pieces kg−1 residue exhibited a higher alpha- and phylogenetic diversity than the other systems studied herein. The plastisphere communities in sprinkling irrigation and vegetable planting systems exhibited a more complex and stable ecological network. The members of the phylum Acidobacteria constituted the main network hubs that were closely connected with other species. KEGG enrichment analyses indicated that maize planting, sprinkling irrigation, and systems with abundant plastic residues presented the highest enrichment of genes associated with human disease. Crop types and irrigation regimes directly influenced residue abundances and soil pH, thereby regulating the plastisphere bacterial communities. Our findings highlight the influence of crop types and irrigation regimes on plastisphere microbiomes and provide a basis for the development of plastic residue management strategies in diverse croplands. [Display omitted] •Plastisphere microbiome was explored by sampling of 75 plastic-mulching croplands.•Crop type and irrigation regime were main drivers of plastisphere bacterial community.•Acidobacteria members were network hubs that were highly related to other taxa.•Pathway related to human disease was higher in maize and sprinkling irrigation system.•Regulation of crops and irrigations on soil pH directly affected the bacterial community.