Antagonistic spectrum of action of saprophite microorganisms on phytopathogenic bacteria

Tashkent State Agrarian University, 2, University street, Tashkent, 100140, Uzbekistan

^* Corresponding author: nigora.хakimova.67@mail.ru

Abstract

The antagonistic activity of 41 strains of various physiological groups of saprophytic soil spore-bearing and non-spore-bearing microorganisms to seven species of phytopathogenic bacteria was studied. It was found that out of 40 strains, only 10 did not have this property, the remaining strains showed an antimicrobial spectrum to phytopathogenic bacteria, but their spectrum of action was not the same. It is known that representatives of useful soil microflora are nitrogen-fixing microorganisms capable of fixing molecular nitrogen, as well as contributing to the enrichment of nitrogen forms digestible for plants, thereby increasing soil fertility. Nitrogen-fixing microorganisms include free-living bacteria of the genus Azotobacter, which most intensively develop in the rhizosphere zone of plant roots and on their surface, as well as symbiotic nodule bacteria of the genus Rhizobium penetrating into the root system of leguminous plants and forming nodules on the bottom. Studies have been carried out to study the effect of metabolites in the studied antagonists on the survival of Azotobacter and nodule bacteria. It has been established that the culture liquid of the studied antagonists does not have a detrimental effect on the studied bacteria of the genus Azotobacter and the genus Rhizobium.