This study examines the effects of kojic acid, chitosan, and their combinations with Bacillus subtilis strains on wheat resistance to dark brown spot. A concentration-dependent immunomodulatory effect of the acid on wheat resistance to Bipolaris sorokiniana was identified: B. subtilis VKM B-2604D and B. subtilis VKM B-2605D strains demonstrated high efficacy in protecting wheat from dark brown spot, reducing plant infestation by 50% compared to the control (80% infestation). Inclusion of kojic acid in the culture fluid of the strains at a concentration of 1.0% increased twice their immunomodulatory activity. It was established that the following compositions possessed the highest inducing activity: B. subtilis VKM B-2604D + B. subtilis VKM B-2605D CF + chitosan 0.1% + 0.5% kojic acid and B. subtilis VKM B 2604D + B. subtilis VKM B 2605D CF + chitosan 0.1% + 1.0% kojic acid. The biological activity of these compositions was 3 and 6 times higher than the effect of the original strains.
Krasnobaeva et al. (Wed,) studied this question.