ANTIMICROBIAL ACTIVITY OF SOIL BACILLI AGAINST PHYTOPATHOGENIC MICROORGANISMS ISOLATED FROM AFFECTED CEREAL PLANTS

Abstract

Aim of this study was to investigate the antagonistic effect of bacilli isolated from the surface of plants and the rhizosphere zone of the soil against pathogens of barley and wheat diseases. Materials and methods. The material for the study was affected barley and wheat samples used to isolate phytopathogenic microorganisms, as well as samples of healthy plants and the rhizosphere soil zone used to isolate bacteria of the genus Bacillus. Manipulations for the isolation and investigation the biological properties of both phytopathogens and bacilli were carried out by traditional microbiological methods. The antagonistic activity of the isolated strains of bacilli against phytopathogens was studied by the block method. Results. From samples of affected wheat and barley were isolated microorganisms identified on the basis of the studied biological properties as Fusarium oxysporum, Sclerotinia sclerotiorum, Xanthomonas arboricola and Pectobacterium carotovorum. The largest proportion of strains was represented by the micromycete Fusarium oxysporum – 53.9%. From samples of the rhizosphere soil zone and leaf-stem mass of healthy wheat and barley plants, 86 strains of bacteria of the genus Bacillus were isolated by microbiological methods. Antagonistic activity was inherent in 54 strains of bacilli against 25% of phytopathogens. All pathogenic microorganisms were inhibited with different intensity by 14 strains of bacilli. Conclusion. The most active bacillus strains (Bacillus spp. 6, 9, 13, 21, 50) were selected for further research.