Antagonistic Activity of Some Plant Growth Rhizobacteria to Fusarium Graminearum

Abstract

Biological control is an efficient and environmentally friendly way to prevent plant disease. In vitro technique was used to investigate the ability of Azospirillum sp., Azotobacter chroococcum, Pseudomonas flourscnes, Bacillus subtilis and Bacillus pumilus in order to control Fusarium graminearum. Results of dual culture interaction test shows that the colony diameter of Fusarium graminearum was significantly reduced (P 0.05) when combined individually with Azotobacter chroococcum, Bacillus pumilus and Bacillus subtilis. However, Azospirillum sp. and Pseudomonas flourscnes comparing to the control did not affect the growth of the pathogen. Volatile metabolites produced by Azospirillum sp. affects F. graminearum negatively (P 0.05) at 3 and 6 days. The culture filtrate of Azospirillum sp. and Bacillus subtilis at three days measurement reduces the pathogen growth significantly. However, the effect of the former disappeared at 7 day while the latter continued affecting the growth of the pathogen significantly. Present study indicates acceptable levels of antagonistic activity of Azospirillum sp., Azotobacter chroococcum, Bacillus subtilis and Bacillus pumilus against Fusarium graminearum in vitro condition.