Abstract
Nitrification oxidizes ammonia in soil into nitrate, leading to significant nitrogen losses, and reducing nitrogen use efficiency (NUE) in agricultural systems. Majority of applied nitrogen fertilizers contribute to environmental issues resulting from nitrification, denitrification, volatilization, leaching, etc., while only 30-50% are absorbed by crops. Nitrification inhibitors (NIs) are compounds designed to slow the conversion of ammonia to nitrate, improving NUE thereby reducing nitrogen loss and mitigating environmental pollution. Chemical NIs, though widely used, pose environmental and health concerns due to their toxicity and persistence. In contrast, biological nitrification inhibitors (BNIs), derived from plant exudates, offer a more sustainable and eco-friendly alternative, effectively inhibiting nitrification without harmful side effects. Advancements in BNIs and their mode of action present promising opportunities for enhancing sustainable farming practices and reducing the environmental impact of nitrogen fertilizers. This review examines the mechanisms of action, effectiveness, and environmental benefits of chemical and biological NIs, highlighting their potential to improve agricultural productivity, reduce nitrogen pollution, and promote greener agriculture.