Assessing soil microbiome alterations in agricultural land exposed to pesticides through amplicon-based sequencing

The degradation of soil health due to intensive pesticide application has emerged as a critical global challenge, undermining ecological sustainability and agricultural productivity. In regions of high agronomic activity such as Dehradun, India, unsustainable practices including monocropping and excessive agrochemical inputs have been implicated in the decline of soil fertility and microbial diversity. This study employs 16S rRNA gene (V3-V4) amplicon-based sequencing to characterize shifts in bacterial community structure for agricultural farming and non-farming soils. Complementary physicochemical analyses revealed significant associations between soil health parameters and microbial community dynamics. Taxonomic profiling revealed distinct microbial signatures in pesticide-contaminated soils, with a notable enrichment of the phyla Proteobacteria, Acidobacteria, Firmicutes, and Actinobacteria. Dominant genera such as Bacillus sp., Chungangia sp., and Streptomyces sp. were identified, indicating their potential functional roles in biogeochemical cycling and adaptive resilience under chemical stress. Functional prediction using PICRUSt2 highlighted key microbial pathways associated with amino acid synthesis, fatty acid synthesis, degradation of aromatic compound, and other essential biochemical processes. These findings highlight the ecological significance of microbial communities in maintaining soil functionality and offer insights into the development of sustainable land management strategies in pesticide-impacted agroecosystems.