Antagonistic potential of siberian strains of Bacillus spp. towards agents causing animal and plant diseases

Bacteria of Bacillus genus are known as the producers of biologically active substances (BAS) including enzymes and antibiotics, whose diversity depends on geographical origin of isolation. BAS production causes high bactericidal and bacteriostatic activity of Bacillus spp. towards zoopathogenic Gram-positive and Gram-negative bacteria and also fungicidal and fungistatic activity towards phyto-pathogenic fungi. In veterinary, preparations and fodder additives, including bacteria of Bacillus genus are used for cattle-plague decrease and weight increase of animals. In plant protection against agents causing diseases the efficacy of Bacillus spp. as the basis of biological fungicides is shown in fields and greenhouses. The aim of this article is to evaluate Siberian wild strains of Bacillus genus bacteria as potential basis of biological formulations for animal and plant health management. The bacterial strains Bacillus subtilis, Bacillus amyloliquefaciens and Bacillus licheniformis were isolated from forest soil of Novosibirsk region and were registered in All-Russian collection of industrial microorganisms (VKPM) and German collection of microorganisms and cell cultures (DSMZ). Pure cultures of phytopathogenic fungi Bipolaris sorokiniana VKPM В-532, Botyrtis cinerea VKPM В-1006, Fusarium graminearum VKPM В-147, F. solani VKPM В-163, F. chlamydosporum VKPM В-899, F. oxysporum VKPM В-349 and F. avenacium VKPM В-623 were received from VKPM. Other test-cultures including the strains of phytopathogenic fungi Alternaria solani, Botrytis cinerea, Fusarium solani and Phytophthora infestans, were isolated by authors from infected plants, and the strains of zoopathogenic bacteria Candida albicans, Citrobacter freundii, Escherichia coli, Klebsiella pneumonia, Proteus vulgaris, Pseudomonas aeruginosae, Salmonella choleraesuis, S. enteritidis, S. peretyphi, S. typhimurium, Shigella son-nei, Sh. flexneri Iia and Staphylococcus aureus were isolated from biological material of animal origin. The strongest antagonistic action of Siberian Bacillus strains towards zoopath-ogens was observed against St. aureus. Towards C. albicans, the strains B. subtilis VKPM В-16041, DSM24613, B. amyloliquefaciens VKPM В-10642, DSM24614, VKPM В-10643 and DSM 24615 were shown to possess high activity. The rest of the bacteria revealed moderate antagonistic activity towards this pathogen. To wards other Gram-negative bacteria used in the experiments - C. freundii, E. coli, K. pneumonia, P. vulgaris, P. aeruginosa, Salmonella sp., Sh. sonnei, Sh. flexneri Ila all Bacillus strains revealed bactericidal action of moderate and weak degree. These very strains of antagonistic bacteria were shown to have inhibitory properties towards most phytopathogens used in the experiments. The highest inhibitory effect towards A. solani causing agent was observed by strains B. amyloliquefa-ciens Ba-1 and Ba-2, B. licheniformis VKPM В-10561, DSM 24609 and B. subtilis Bs-1. The strains B. subtilis Bs-1, B. amyloliquefaciens Ba-1 and Ba-2В revealed high activity in growth suppression of root rot causing agent B. sorokiniana. The same strains were very active compared with others towards plant grey mold causing agent B. cinerea. Simultaneously, the strains B. licheniformis did not suppress B. cinerea growth. All Bacillus spp., studied here, showed a high level of inhibitory activity towards Solanaceae phytophtora causing agent Ph. infestans. No antagonistic activity towards F. solani VKPM В-163 was displayed by bacterial strains B. licheniformis Bl-1; VKPM В-10562, DSM 24610, VKPM В-10564 and DSM 24612. The antagonistic potential of Siberian strains of bacteria of Bacillus genus towards zoopathogenic and phytopathogenic microorganisms revealed in this work testify of promising study of isolated antagonistic bacteria as a basis of ecologically safe biopreparations for plant and animal health management.

Keywords

Authors

References