Pesticide Degradation by Soil Bacteria: Mechanisms, Bioremediation Strategies, and Implications for Sustainable Agriculture

Pesticides remain indispensable for modern agriculture, yet their persistence in soil poses serious ecological and human-health risks through bioaccumulation, groundwater contamination, and impacts on non-target organisms. Although extensive research exists on pesticide degradation, most reviews separate biochemical pathways, environmental controls, and applied bioremediation strategies, limiting the ability to predict real-world field performance. This review integrates mechanistic enzymology, soil ecological responses, quantitative degradation kinetics, and emerging synthetic biology innovations into one unified framework. Soil bacteria including Pseudomonas, Bacillus, Rhodococcus, and Arthrobacter degrade organophosphates, carbamates, triazines, neonicotinoids, pyrethroids, and organochlorines through hydrolysis, oxidation, nitroreduction, and ring-cleavage pathways, often supported by plasmid-encoded genes and horizontal gene transfer. Bioaugmented systems typically achieve 70 to 95 percent removal within 10 to 30 days, with highly efficient cases such as Pseudomonas putida KT2440 removing 96 percent chlorpyrifos in 5 days, Rhodococcus koreensis mineralizing 98 percent endosulfan in 7 days, and Arthrobacter sp. AD26 degrading 95 percent atrazine in 72 h. Field-scale Azotobacter–Pseudomonas consortia have reduced chlorpyrifos from 25 mg kg−1 to less than 1 mg kg−1 within 30 days. Environmental conditions strongly influence degradation efficiency. Acidic soils increase pyrethroid half-lives by two to three times, anaerobic conditions can extend pesticide persistence from months to years, and drought or low organic matter reduces microbial activity by 60 to 80 percent, increasing neonicotinoid DT50 to more than 1000 days. Advances in omics, metagenomics, kinetic assays, and synthetic biology now enable engineered strains and synthetic consortia capable of more than 90 percent mineralization within 7 to 21 days. By linking molecular mechanisms, ecological constraints, quantitative outcomes, and emerging biotechnologies, this review provides a predictive roadmap for climate-resilient, scalable, and sustainable bioremediation strategies.