The effect of <i>N</i>‐oxide phenazine producer <i>Lysobacter antibioticus</i> on bacterial leaf streak in rice and the rhizosphere microbial community

Abstract Bacterial leaf streak (BLS) of rice, caused by Xanthomonas oryzae pv. oryzicola , severely compromises crop yield and grain quality. This study evaluates the biocontrol potential of Lysobacter antibioticus OH13, a soil bacterium producing the N ‐oxide phenazine antibiotic myxin, against BLS. Under greenhouse conditions, the OH13 strain, its cell‐free supernatant, and purified myxin significantly reduced lesion lengths in infected rice plants. Field trials demonstrated that myxin (20 mg/L) achieved a disease control efficacy of 77.41%, comparable to the chemical agent 30% zinc thiazole, whereas OH13 itself exhibited an efficacy of 65.26%. Rhizosphere microbiome analysis revealed that OH13 reshaped the bacterial community composition, enriching taxa, such as Myxococcia and Actinomycetota, suggesting a dual mechanism that combines direct antimicrobial activity and microbiome‐mediated suppression. To enhance myxin production, we employed a combinatorial strategy that integrates atmospheric and room temperature plasma mutagenesis, targeted genetic engineering, and medium optimization, achieving a final myxin yield of 3.19 times the initial level. These findings highlight the potential of L. antibioticus OH13 and myxin production as a sustainable and multifunctional alternative for BLS management.