Влияние состава питательной среды на рост и антифунгальную активность бактерий р. Bacillus – основы экспериментальных образцов биофунгицидов для экологизированной системы защиты растений

Abstract

The article presents the results of the studies of the influence of the nutrient medium composition for the cultivation of Bacillus bacteria. We compared standard microbiological media and optimized nutrient medium according to criteria such as the number of colony forming units in liquid culture and antifungal activity against the test culture of F. graminearum fungus. It was noted that the number of colony forming units of LC based on the B. subtilis BZR 336g strain on the optimized medium turned out to be significantly higher than on King B media and potato-glucose medium and amounted to (8.7±0.66) x 1010 CFU/ml, for B. subtilis BZR 517 strain titer on an optimized medium was (7.2±0.42) x 1010 CFU/ml. Antifungal activity on an optimized nutrient medium for B. subtilis BZR 336g was strain 83.5%, for B. subtilis BZR 517 strain – 61.1%. We found the positive effect of experimental samples of biofungicides obtained with the help of an optimized nutrient medium on the growth and development of winter wheat plants against the background of artificial infection in a climatic chamber. The treatment of winter wheat seeds with experimental samples of biofungicides ensured biological efficiency from 35.4% to 60.8% with the efficiency of the Kinto Duo chemical standard, KS 38.9%, Fitosporin-M biological standard – 28.9%. It was noted that seed germination in the variant with biofungicide treatment based on the optimized medium was 20-30% higher than in the variants with standard media. Seed treatment with experimental samples of biofungicides obtained on various nutrient media showed a statistically significant increase in the biometric parameters of winter wheat seedlings.