Obtaining effective biodestructors of fungicidal drugs for environmental agrobiocenoses’ maintenance sustainability

Abstract

Agrobiocenoses are highly productive communities. However, their resistance is low due to the artificially limited species diversity, susceptibility to diseases and pests, and the impossibility of self-recovery. The constant use of pesticides for plant protection further reduces the resistance of agrocenoses due to the toxicity of the components for the soil microbiota and pollinating insects. The accumulation and migration of toxic components of pesticides leads to an increase in the environmental load on surface water bodies and aquatic organisms. The impossibility of abandoning the use of fungicidal preparations and the need to develop ways to increase the ecological stability of agrobiocenoses determined the relevance of the studies described in the article. In the course of the experiment, pure cultures of 9 microbial strains-destructors of strobilurins and triazoles - active substances of widely used fungicides -were isolated from environmental objects. A comparative assessment of the ability of the isolated strains to consume high concentrations of azoxystrobin and cyproconazole was carried out. It was found that the Bacillus thuringiensis strain, which is capable of growing on media containing up to 100 APC for soil in the absence of other carbon sources, has the greatest activity. B. thuringiensis is promising as the basis of a biological product for the recultivation of soils contaminated with fungicides of the strobilurin and triazole classes. To obtain the biomass of the biodestructor, the optimal cultivation parameters were determined: temperature 37 ºC and the composition of the nutrient medium based on glucose and peptone with microelements: Mg, Fe, Zn, Mn, B.