The effect of Bacillus strains, B. subtilis 16 and B. pumilus 11, on two barley diseases caused by Bipolaris sorokiniana (Sacc.) Shoemaker has been studied. It was found that the activity depends on both the resistance of the cultivar against disease and the bacterial strain. The severity of spot blotch of barley decreased significantly when the cell suspension of B. subtilis strain16 was sprayed on the leaves of disease-susceptible cultivars Nashсhadok, but failed to inhibit the disease on the leaves of resistant cultivars. Applying the cell suspensions into plant growth media significantly inhibited the common root rot on susceptible cultivar Syaivo, which, however, was not accompanied by an increase in the biomass of seedlings. A significant increase in the weight of shoots and roots of seedlings was observed on cultivars with medium resistance to the disease: Sebastian and Antey
Bacillus spp.; barley; biological control; Bipolaris sorokiniana; common root rot; spot blotch