[Objective] The study aimed to explore the antibacterial activity and stability of antagonistic bacteria P72 against wheat scab.[Method] The Bacillus subtilis P72 was inoculated into fermentation media with the inoculation amount 5%,then cultured on shaking table at 28 ℃ for 48 h and centrifuged at 8 000 r/min for 10 min.The supernatant of fermentation broth was purified and then the genetic stability,thermal stability and pH stability were detected.[Result] By DEAE-52 ion exchange chromatography,the protein eluted by 0.5 mol/L NaCl solution possessed the strongest antagonistic ability against wheat scab pathogen.The SDS-PAGE electrophoresis showed that the molecular weight of the purified protein with antibacterial effect was 40 kD.By stability test,the antibacterial substance produced by P72 strain showed heritable antagonistic activity,high stability below 60 ℃,stability to acid and unstability to alkali.[Conclusion] The antagonistic bacteria P72 had strong antagonistic ability to wheat scab pathogen,stable antibacterial activity and thermal stability,so it would possess a wide development prospect.
