Biocontrol activity of endophytic fungus of barley, Microdochium bolleyi, against Gaeumannomyces graminis var. tritici

In this study, two isolates of genus Microdochium (W2 and B26) was isolated from the roots of healthy barley plants in agricultural fields from Kermanshah province in 2014 and were identified as Microdochium bolleyi based on morphological and molecular characteristics. Dual culture studies revealed that W2 and B26 inhibit 45% and 20% of the radial growth of Ggt in turn. The W2 isolate was inoculated on barley roots in order to assess its effect on suppressing take–all disease and promoting the growth of barley plants. Regarding suppression of disease test, pathogenicity index (the percentage of necrosis root disease severity) for the plants that were inoculated with endophytic M. bolleyi and Ggt at the same time was 0.6, compared to 4.4 for the plants that were inoculated with Ggt alone. M. bolleyi also increased significantly root fresh weight by 31.21%, aerial fresh weight by 15.15%, root length by 3.0%, aerial length by 2.35%, root dry weight by 30.94% and aerial dry weight by 12.28% which were significant differences at the 5% level. For growth-promoting effects, growth parameters were evaluated and the results showed M. bolleyi effectively promoted root fresh weight by 60.0%, aerial fresh weight by 38.46%, root length by 4.54%, aerial length by 7.21%, root dry weight by 60.43% and aerial dry weight by 38.60%, which were significant in 5% level. To our knowledge, this is the first report of M. bolleyi for the mycobiota of Iran and it may be further used as a biocontrol agent.