Scientific Journal of KubSAU

Progress in crop production depends on many factors; including the important measure is the protection from pathogenic microorganisms. Various chemicals are used to control phytopathogens, such as natural and artificially synthesized ones. Natural compounds are more environmentally friendly, in most cases less toxic and quickly destroyed. The purpose of this work was to find strains of actinobacteria that have antifungal activity and are considered by us as possible sources of antifungal compounds for agricultural purposes. We selected 10 strains of actinobacteria that were isolated from typical regions of Russia. These strains were active against the fungal test strains Saccharomyces cerevisiae RIA 259 and Aspergillus niger INA 00760 when deep cultured. To determine the activity of selected actinobacteria against phytopathogenic fungi, 6 strains isolated from affected plants were used as tests. Morphological and genetic analysis methods have shown that the selected actinobacteria strains belong to two genera and are represented by the following species: Nocardia soli, Streptomyces antibioticus, S. bottropensis, S. chartreusis, S. chromofuscus, S. hydrogenans (2 isolates), S. lusitanus, S. netropsis, S. peucetius. Phytopathogenic fungi are represented by the following species: Fusarium armeniacum (2 isolates), Fusarium culmorum, Alternaria tenuissima (2 isolates), Bipolaris sorokiniana. As a result, it was found that under conditions of submerged cultivation on nutrient media, actibacteria form substances that inhibit the growth of all phytopathogenic tests used in the experiment. The representatives of species N. soli INA 01217, S.chromofuscus INA 01211, S. lusitanus INA 01218, S. netropsis INA 01190 and S. peucetius INA 01255 have not been described as having antifungal activity previously, so we consider them to be the most promising for chemical research to identify new antifungal antibiotics