Impact of Cypermethrin (Arpon G) on Soil Health and Zea mays Growth: A Microbiological and Enzymatic Study

In defining the research objective, consideration was given to the expanding range of applications of third-generation pyrethroids, including cypermethrin—the active substance in Arpon G preparation. The interest in cypermethrin is due to its high thermostability and photostability. This study verified the effect of Arpon G on both the soil condition and the growth and development of Zea mays. To this end, the alpha and beta diversity of bacterial and fungal communities were characterized using the NGS (Next Generation Sequencing) method, as was the response of soil enzymes. The positive response of Z. mays to the soil application of cypermethrin corresponded to higher soil microbial and biochemical activity. Sowing the soil with Z. mays moderated changes in the biodiversity of alpha- and beta-bacterial communities to a greater extent than cypermethrin. The influence of both parameters was less significant for fungi. Although bacteria belonging to the Actinobacteria phylum and fungi from the Ascomycota phylum dominated in the soil, the use of Arpon G reduced the abundance of unique nucleotide sequences in the mycobiome to a greater extent than in the bacteriobiome. The inhibitory potential of Arpon G was only evident for acid phosphatase (by 81.49%) and arylsulfatase (by 16.66%) in the soil sown with Z. mays. The activity of catalase, dehydrogenases, β-glucosidase, arylsulfatase, and alkaline phosphatase was most strongly associated with the abundance of bacteria, while dehydrogenases were correlated with the abundance of fungi at the genus level. Arpon G can, thus, be considered a safe insecticide for soil conditions and, consequently, for its productive function.