児玉 浩明

Compost is used worldwide as a soil conditioner for crops, but its functions remain unclear. Here, the omics profiles of carrots and soil amended with compost fermented by thermophilic Bacillaceae, as a compost model, are classified based on information on carrots' growth, color, and taste characteristics. The production of carrots and their antioxidant activity were significantly increased by compost exposure, as was their content of carotenes, essential carrot nutrients. Furthermore, omics profiles revealed that carrots' growth, red color, and taste could be increased by altering characteristic leaf, root, and soil metabolites by compost exposure. In particular, structural equation modeling statistically predicted a strong association with nitrogen-cycle related-soil bacteria candidates, which could modulate nitrogen fixation and anaerobic ammonium oxidation (anammox), affected by compost. These observations statistically provide a novel perspective on potential sustainable compost as an organic fertilizer that has the role of preserving the environment.