Seed Priming with Carbon Dots Enhances Rice Growth and Resistance by Promoting Root Development and Recruiting Root-Attached Microorganisms

Seed priming presents a promising strategy for regulating plant growth and development by using nanomaterials. However, the response of plant roots and their associated microorganisms to nanopriming remains poorly understood. In this study, carbon dots (CDs) were synthesized and applied for rice seed priming. The results showed that CD priming significantly enhanced photosynthesis and growth in rice seedlings. Notably, CDs improved root architecture, increased cell wall thickness and lignification, enhanced root vitality, stimulated Ca 2+ influx and K + efflux, and upregulated genes related to aquaporins and stress resistance. Microbial analysis revealed that CD priming significantly enriched microbial communities involved in nitrogen transformation and absorption while reducing pathogenic species. Consequently, these effects induced by CD priming on rice seedlings conferred significant resistance to salt, 2,4-D, and 2,4-D-Na stresses. This study provides a sustainable approach to promoting plant growth and mitigating environmental stress.