Role of psychrotrophic fungal strains in accelerating and enhancing the maturity of pig manure composting under low-temperature conditions

Abstract

This study investigatedthe effects of applying psychrotrophic cellulose-degrading fungion cellulase production, fungal community structure, and maturity of pig manure (PM) compost under low-temperature conditions. Three psychrotrophic fungal strains were isolated and identified, and after the cold-active cellulase production conditions were optimized, they were inoculated into PM compost. While the control (CK) compost temperature failed to reachthe thermophilic stage, the inoculated compost temperature reached it within 3 days and was maintained for up to 17 days. Fungal inoculants improved fungal community structure at the end of composting, as suggested by network analysis. Principal component analysis revealed that the germination index (GI), total phosphorus (TP), total potassium (TK), and total nitrogen (TN) were the most influential physicochemical parameters affecting compost maturity. The results of the compost products reflected the suitability of the compost as a fertilizer. This study indicated that newly identified strains positively impacted composting at low temperatures.

Keywords: Cold-active cellulase; Fungal community; Low-temperature; Pig manure compost; Psychrotrophic fungi.