Mitigation of nitrous oxide emission through fertigation and ‘N’ inhibitors – A sustainable climatic crop cultivation in tomato

Abstract

The impact of nitrous oxide (N2O) released from the fertilized agro-ecosystems are of increasing concern. Governing fertilizer requirements and utilizing nitrification inhibitors (NI) are effective methodologies to increase nitrogen retention and reduce N2O emissions from soil. Therefore, the effect of potassium thiosulfate (KTS) and neem-coated urea (NCU) on N2O efflux under irrigated tomato cultivation was assessed. Soil Test Crop Response (STCR) based recommendation of NPK with normal Urea and KTS at 1% of applied N (183:160:125 kg ha−1) (STCR-U + KTS) recorded the least N2O emission and high efficiency in suppressing the nitrate reductase activity. STCR-NCU was on par with STCR-U + KTS, reporting a higher reduction of N2O (21.1, 31.2, and 34.4% during the basal application, 1st and 2nd top dressing, respectively) compared to the blanket recommendation of nutrients. Similarly, STCR-U + KTS recorded the highest reduction (26.2, 25.6, and 30.9% during the basal application, 1st and 2nd top dressing, respectively) after fertilizer application. Besides, the yield of tomatoes is increased in the STCR-NCU (14.08%) and STCR-U + KTS (12.48%) with good quality fruit along (AA, Lycopene, and TSS contents) with low N2O emissions. The DeNitrification-DeComposition (DNDC) model further revealed that the simulated data and assessed findings were in good accord, proving the model's reliability and use as a tool for predicting the efficiency of fertilizer application.