Changes in microbiological properties of soil during fungicide degradation

Abstract

Abstract Laboratory tests were performed on sandy loamy soil to establish the relations between bacterial diversity, soil enzyme activity and degradation of Amistar 250 SC, Falcon 460 EC and Gwarant 500 SC fungicides. Apart from carrying out microbiological and biochemical analyses, the residues of active substances from the tested fungicides were determined. Structural diversity of was determined based on the next-generation sequencing (NGS) method, and fungicide residues the liquid chromatography tandem-mass spectrometry (LC-MS/MS). It was found that changes in bacterial diversity occurred in the soil subject to fungicide treatment, particularly at the family and genus level. Proteobacteria, Firmicutes and Actinobacteria were prevailing in all soil samples. Bacillus occurred both in the control soil and in the soil treated with fungicides, while Pseudonocardia occurred only in the fungicide-treated soil. Of all the fungicides tested, the biggest changes in bacterial diversity were caused by Gwarant 500 SC. The preparations tested not only affected the composition of soil microbiota, but also contributed to changes in the biochemical properties of soil by inhibiting the activity of almost all tested enzymes, with the exception of alkaline phosphatase and β-glucosidase. Chlorothalinil was the fastest degraded in the soil and spiroxamine at the slowest.