Changes in Bacterial and Fungal Community of Soil under Treatment of Pesticides

Experiments were carried out in soil microcosms with the treatment of pesticide formulations-imidacloprid, benomyl, and metribuzin in single and tenfold application rates. For additional stimulation of microorganisms, a starch-mineral mixture was added to some variants. For all samples, high-throughput sequencing on the Illumina MiSeq platform of the V4 (16S rRNA) and ITS1 (18S rRNA) fragments was carried out. As a result, it was possible to establish the characteristic changes in the structure of the soil fungal and bacterial communities under pesticides application. The application of pesticides was accompanied by dramatic shifts in alfa-diversity of the fungal community. The phylum Basidiomycota was likely to be involved in the degradation of pesticides. The changes in the relative abundance of the genera Terrabacter, Kitasatospora, Streptomyces, Sphingomonas, Apiotrichum, Solicoccozyma, Gamsia, and Humicola can be proposed as an indicator of pesticide contamination. It is suggested to use these markers for large-scale assessment of the effect of pesticides on soil microbial communities instead of classical integral methods, including within the framework of state registration of pesticides. It is also recommended to research the effect of pesticides on the soil microbiome during artificially initiated successions using the additional source of carbon.

Automated summary

This study investigated the impact of pesticide formulations on soil fungal and bacterial communities in soil microcosms. The application of pesticides led to significant changes in the structure of these communities, particularly in the alpha-diversity of the fungal community. Certain genera showed changes in relative abundance that could serve as indicators of pesticide contamination. It is recommended to use these markers for large-scale assessment of the effects of pesticides on soil microbial communities.