Dynamic changes in the cellulolytic microbial community during oat straw decomposition in soil
Abstract
Due to poorly understood interactions between microorganisms, the decomposition of straw is a dynamic process that is accompanied by the succession of the microbial decomposing community. The soil microbiome can provide a supply of potentially active cellulolytic microbes since soil is a complex ecological niche. By placing nylon bags containing sterilised oat straw in pots filled with chernozem soil and incubating them for 6 months, we conducted an experiment on the de novo colonisation of oat straw by the soil microbial population. The objective was to use conventional sequencing techniques to look into how the decomposer microbiota changed during this process. The three phases of the bacterial succession during straw decomposition were high microbial activity and low diversity in the early phase (first month), low activity and low diversity in the middle (second to third month), and low activity and high diversity in the late phase (fourth to sixth months). Following analysis of the amplicon sequencing data, three co-changing phylotype groups corresponding to these periods were identified. For bacteria, Pseudomonadota, Bacteroidota, Bacillota, and Actinobacteriota, and Ascomycota for fungi, the cellulolytic members were numerous in the early active phase, and by the conclusion of the phase, the majority of the primary phylotypes had vanished.