Enhancing Composting Efficiency: Thermophilic Lignocellulolytic Microbes for Bioconversion of Rice and Wheat Straw

Abstract

Effective management of large amounts of crop residue from agricultural farms is crucial. Composting is a viable strategy for rice and wheat straw management, but traditional methods are inefficient due to the recalcitrant nature of the straw. This study aimed to identify and utilize thermophilic lignocellulolytic bacteria for efficient bioconversion of rice and wheat straw into compost. Samples were collected from hot springs in Madhya Pradesh and Chhattisgarh, leading to the isolation of 101 bacterial strains, of which 20 showed significant cellulolytic and lignolytic activity. Seven key isolates (five bacteria and one fungus) were further characterized and applied to compost rice and wheat straw in controlled conditions. The composts treated with these bacteria showed improved nutrient content and enzymatic properties compared to untreated compost. Specifically, in wheat straw, nitrogen (0.98%), phosphorus (1.49%), and potassium (1.37%) were higher than in the control (N: 0.69%, P: 0.99%, K: 0.86%). Similarly, in paddy straw, treated compost had higher N (1.17%), P (0.55%), and K (2.10%) compared to the control (N: 0.87%, P: 0.28%, K: 1.78%). The results demonstrated that these microbial isolates enhanced the composting process, improving compost maturity and nutrient content. This study recommends the formulation of these thermophilic lignocellulolytic bacteria for efficient crop residue composting. By reducing the reliance on straw burning, this microbial approach offers an eco-friendly alternative for sustainable agriculture and climate change mitigation.