Isolation and characterization of endophytic bacteria for controlling root rot disease of Chinese jujube

Aim Fusarium oxysporumis the primary pathogen causing root rot disease that severely affects cultivation of jujube fruit in the Xinjiang province of China. The aim of this study was to identify endophytic bacteria in healthy jujube organs that could effectively suppressF. oxysporumgrowth. Methods and Results Different plant organs (leaves, twigs and roots) were collected from healthy Chinese jujube cultivated in southern Xinjiang province of China. The endophytic bacteriumBrevibacterium halotoleransJZ7 was selected for its strong antagonistic activity and growth-promoting characteristics. Gas-chromatography mass-spectrometry analysis showed that acetoin, 2,3-butanediol and fenretinide were the three dominant volatile organic compounds produced by strain JZ7. Fenretinide strongly suppressed spore germination ofF. oxysporum in vitro. Pot experiments showed that strain JZ7 colonized both the roots and rhizosphere soil of Chinese jujube and significantly reducedF. oxysporumlevel in jujube rhizosphere soil. Conclusion We demonstrated thatB. halotoleransJZ7 can be developed into a biological control agent to combat root rot disease of Chinese jujube in the Xinjiang province of China. Significance and Impact of the Study The suggested strategy for biological control of jujube root rot disease is fully in accordance with the current principles of sustainability.