The Impact of Pesticides on the Microbial Community of Agrosoddy-Podzolic Soil

The impact of three types of pesticides (herbicide metribuzin, insecticide imidacloprid, and fungicide benomyl) on the structure of microbial complexes and indicators of biological activity of agrosoddy-podzolic soil (Moscow oblast) has been assessed using the method of next-generation sequencing (NGS). The pesticides have been applied both separately and together at one- and tenfold rates. It has been found that pesticides have a greater impact on the fungal community in comparison with the prokaryotic community; in the latter, only changes in the abundances of the phyla of Actinobacteria and Proteobacteria have been observed. The study of fungal communities with the use of molecular-genetic analysis has revealed two dominant divisions of fungi in all soil samples: Ascomycota (72.6 +/- 8.0%) and Basidiomycota (26.0 +/- 7.7%). Moreover, in the samples treated with tenfold rate of pesticides (both in mixture and separately), the abundances of representatives of the Basidiomycota division have increased. Pesticide application has a short-term stimulating effect on the carbon content of microbial biomass. It has been shown that insecticide imidacloprid stimulates nitrogen fixation, whereas other types of pesticides do not affect this factor.