The role of Bacillus bacteria in the decomposition of plant residues

An excess of plant residues in fields creates conditions that limit plant growth and significantly affect changes in the composition of soil microorganisms.

🪏 Plant residues that are difficult to decompose form an insulating layer that hinders airflow, thereby:

• create anaerobic conditions in which putrefaction occurs, and the population of beneficial microorganisms is reduced,

• lowers soil pH, which hinders proper plant growth,

• leads to “nitrogen starvation” due to rapid nitrogen depletion.

🍂 Of course, not all plant residues create unfavorable conditions. It depends on the carbon-to-nitrogen ratio and the content of cellulose, hemicellulose, and lignin, which, as in the case of straw, are more difficult for microorganisms to break down.

🦠 In such cases, bacteria of the genus Bacillus may prove helpful, as their enzymes enable the breakdown of hard-to-decompose organic compounds.

🧪 These enzymes include cellulases, which break down cellulose, as well as xylanases and hemicellulases, which break down hemicellulose.

📖 A 2025 study using Bacillus to reduce the amount of wheat and rapeseed straw showed:

• a 23.45% reduction in wheat straw biomass over 7 days,

• an average of 18.46% less rapeseed straw biomass over 7 days.

✅ Bacteria of the genus Bacillus can effectively support the decomposition of plant residues, thereby reducing their negative impact on soil microorganisms and crops.