Triazoles and Strobilurin Mixture Affects Soil Microbial Community and Incidences of Wheat Diseases

Anastasia V Vasilchenko; Darya V Poshvina; Mikhail V Semenov; Vyacheslav N Timofeev; Alexandr V Iashnikov; Artyom A Stepanov; Arina N Pervushina; Alexey S Vasilchenko

doi:10.3390/plants12030660

Triazoles and Strobilurin Mixture Affects Soil Microbial Community and Incidences of Wheat Diseases

Plants (Basel). 2023 Feb 2;12(3):660. doi: 10.3390/plants12030660.

Authors

Anastasia V Vasilchenko¹, Darya V Poshvina¹, Mikhail V Semenov^{1

2}, Vyacheslav N Timofeev³, Alexandr V Iashnikov¹, Artyom A Stepanov¹, Arina N Pervushina⁴, Alexey S Vasilchenko¹

Affiliations

¹ Laboratory of Antimicrobial Resistance, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia.
² Laboratory of Soil Carbon and Microbial Ecology, Dokuchaev Soil Science Institute, 119017 Moscow, Russia.
³ Scientific Research Institute of Agriculture for Northern Trans-Ural Region-Branch of Tyumen Scientific Centre SB RAS, 625003 Tyumen, Russia.
⁴ International Integrated Research Laboratory for the Study of Climate Change, Land Use and Biodiversity, Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia.

Abstract

Pesticides are widely used in agriculture as a pest control strategy. Despite the benefits of pesticides on crop yields, the persistence of chemical residues in soil has an unintended impact on non-targeted microorganisms. In the present study, we evaluated the potential adverse effects of a mixture of fungicides (difenoconazole, epoxiconazole, and kresoxim-methyl) on soil fungal and bacterial communities, as well as the manifestation of wheat diseases. In the fungicide-treated soil, the Shannon indices of both fungal and bacterial communities decreased, whereas the Chao1 indices did not differ compared to the control soil. Among bacterial taxa, the relative abundances of Arthrobacter and Sphingomonas increased in fungicide-treated soil due to their ability to utilize fungicides and other toxic compounds. Rhizopus and plant-beneficial Chaetomium were the dominant fungal genera, with their prevalence increasing by 2-4 times in the fungicide-treated soil. The genus Fusarium, which includes phytopathogenic species, which are notably responsible for root rot, was the most abundant taxon in each of the two conditions but its relative abundance was two times lower in fungicide-treated soils, consistent with a lower level of disease incidence in plants. The prediction of metabolic pathways revealed that the soil bacterial community had a high potential for degrading various pollutants, and the soil fungal community was in a state of recovery after the application of quinone outside inhibitor (Q_oI) fungicides. Fungicide-treated soil was characterized by an increase in soil microbial carbon, compared with the control soil. Collectively, the obtained results suggest that the application of difenoconazole, epoxiconazole, and kresoxim-methyl is an effective approach for pest control that does not pose a hazard for the soil ecosystem in the short term. However, it is necessary to carry out additional sampling to take into account the spatio-temporal impact of this fungicide mixture on the functional properties of the soil.

Keywords: difenoconazole; epoxiconazole; kresoxim-methyl; non-targeted action; pesticide contamination; soil microbiome; soil quality.

Grants and funding

075-15-2021-1345 unique identifier RF----193021X0012/Ministry of Science and Higher Education of the Russian Federation