Fusarium culmorum is one of the most important pathogens of wheat crop in Iran and worldwide. Because of the dangers of using pesticides, biological control using antagonistic bacteria, as a suitable alternative to protect plants against important pathogens has recently been considered by scientists. In this study, in order to isolate rhizosphere antagonist bacteria from soil around wheat, sampling was done. One gram of this soil was collected and transferred to a sterile Falcon and the bacteria were separated on the N.A. medium. After double-culture assay, 19 bacterial isolates with antagonistic activity selected for future analysis. The isolates Pf02, Pf03, Pf05, Pf08, and Pf04 had the highest inhibition zone, respectively, and the lowest inhibition belonged to two isolates, Ba10 and Ba14. In order to confirm the antagonistic properties of these isolates in greenhouse conditions, first the soil of the pots was infected with the pathogenic fungus Fusarium and healthy wheats were planted in the seedling tray and the roots of the wheats were smeared with antagonistic bacteria before planting in the infected pots with Fusarium. Greenhouse tests showed that all bacteria significantly reduced the disease index (minimum 23% and maximum 33.3%). In addition, comparison of shoot and root length to control, indicated the ability of antagonist bacteria to induce plant resistance induction. The results of sequencing of two selected species Pf02 and Pf05 showed that these isolates belonged to Pseudomonas aeruginosa and P. protegens, respectively.

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