Identification of driving factors of lignocellulose degrading enzyme genes in different microbial communities during rice straw composting

Abstract

The study aims to clarify the driving factors of lignocellulose degrading enzyme genes abundance during rice straw composting. Lignocellulose degrading strains b4 (Bacillus subtilis), z1 (Aspergillus fumigatus) were inoculated into pure culture, respectively. Meanwhile, three rice straw composting groups were set up, named CK (control), B4 (inoculating b4) and Z1 (inoculating z1). Results confirmed the composition of functional genes related to lignocellulose metabolism for strains. Lignocellulose degrading enzyme genes abundance was up-regulated by inoculation, which promoted the decomposition of lignocellulose. Modular microorganisms, such as Actinobacteria, Proteobacteria, Ascomycetes and Basidiomycetes, were identified as driving factors that affected lignocellulose degrading enzyme genes abundance. pH, organic matter and soluble sugar content affected lignocellulose degrading enzyme genes abundance by affecting modular microorganisms. In addition, a potential priming effect was put forward based on the driving factors. This study provided theoretical guidance for regulating the abundance of lignocellulose degrading enzyme genes to promote lignocellulose degradation.