Host genetics regulate the plant microbiome.

Plants recruit a taxonomically diverse microbial community, collectively termed the plant microbiome, that includes mutualists, pathogens, and commensals. These myriad microorganisms are robustly intertwined with their hosts and can determine plant fate by influencing fitness and growth or offering protection from detrimental bacteria, fungi, and herbivores. Recent studies have revealed significant effects of host genome diversity on plant-microbiome assembly and how host genetics determine microbiome composition, which is crucial for beneficial functions. The few host loci identified through genome-wide association studies suggest that genes involved in plant development, immunity, nutrient uptake, and root exudates regulate plant-microbiome community structure. Elucidating the role of host genetics in plant-microbiome assembly is key to understanding how plant-microbiome interactions are evolving and how to unlock the breeding and engineering potential of the microbiome for sustainable agriculture.

Does bacterial community succession within the polyethylene mulching film plastisphere drive biodegradation?

Agricultural fields are severely contaminated with polyethylene mulching film (PMF) and this plastic in the natural environment can be colonized by biofilm-forming microorganisms that differ from those in the surrounding environment. In this study, we investigated the succession of the soil microbial communities in the PMF plastisphere using an artificial micro-ecosystem as well as exploring the degradation of PMF by plastisphere communities. The results indicated a significant and gradual decrease in the alpha diversity of the bacterial communities in the plastisphere and surrounding liquid. The community compositions in the plastisphere and surrounding liquid differed significantly from that in agricultural soil. Phyla and genera with the capacity to degrade polyethylene and hydrocarbon were enriched in the plastisphere, and some of these microorganisms were core members of the plastisphere community. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis detected increases in metabolism pathways for PMF plastisphere Xenobiotics Biodegradation and Metabolism, thereby suggesting the possibility of polyethylene degradation in the plastisphere. Observations by scanning electron microscopy (SEM) and confocal laser scanning microscopy demonstrated the formation of biofilms on the incubated PMF. SEM, atomic force microscopy, Fourier transform infrared spectroscopy and water contact angle detected significant changes in the surface microstructure, chemical composition and hydrophobicity change of the films, thereby suggesting that the plastisphere community degraded PMF during incubation. In conclusion, this study provides insights into the changes in agricultural soil microorganisms in the PMF plastisphere and the degradation of PMF.