Univrsity of Tehran Press Iranian Journal of Field Crop Science 2008-4811 54 2 2023 06 22 The Effect of Nitrification Inhibitor on Grain Yield of Wheat Cultivars and Some Soil Properties under Conventional and No-Tillage Systems The Effect of Nitrification Inhibitor on Grain Yield of Wheat Cultivars and Some Soil Properties under Conventional and No-Tillage Systems 31 46 92019 10.22059/ijfcs.2022.345822.654927 FA Ghorban Khodabin Department of Agronomy, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran Ashkan Jalilian Department of Agronomy and Plant Breeding, Faculty of Agriculture, University of Tehran, Karaj, Iran 0000-0001-5544-8249 Ehsan Zandi Esfahan Research Institute of Forests and Rangelands, Agricultural Research, Education, and Extension Organization (AREEO), Tehran, Iran. Nima Shahbazi Department of Agronomy and Plant Breeding, Faculty of Agriculture,, University of Tehran, Karaj, Iran 0000-0001-9985-701X Fatemeh Amini Department of Agronomy and Plant Breeding, Faculty of Agricultural Science, Islamic Azad University, Shahr-e-Qods Branch, Iran 0000-0001-5582-2368 Shiva Ghaznavi Department of Agricultural Economics, Faculty of Agriculture, University of Tehran, Karaj, Iran 0009-0007-5333-1478 Ali Heidarzadeh Department of Agronomy, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran 0000-0001-6680-9257 Journal Article 2022 07 17 In agriculture, nitrogen fertilizer does not effectively absorb by plants. Several biological activities in the soil convert N into various compounds. Nitrogen oxide (N₂O) is an influential greenhouse gas formed in soils due to nitrification and denitrification process. Nitrapyrin (NI) combined with ammonium (NH₄⁺) based fertilizers is an effective technique for minimizing the N loss in agricultural soils by regulating ammonia-oxidizing. This research was conducted during 2019-2020 to determine the effect of NI on nitrogen emissions in soil and crop yield of wheat cultivars at three urea (UR) levels, NI+urea (NIU), and control (CO) on two cultivars (Rakhshan and Pishgam) and two tillage systems (No tillage (NT) and conventional tillage (CT)). The highest amounts of NH₄⁺, NO₃^- and N₂O were found at the stem elongation stage. While NIU fertilizer treatment yielded the highest NH₄⁺ (18.38 mg kg⁻¹), the UR fertilizer treatment yielded the highest NO₃^- (25.96 mg kg⁻¹) and N₂O (0.0192 kg N₂O-N ha⁻¹ day⁻¹). At all developmental stages in the CT and NT systems, the NIU treatment decreased the average nitrification of NH₄⁺ and its conversion to NO₃^- by 27.81 and 15.45%, respectively. Our findings, thus, showed that NI application in conjunction with UR could highly reduce N₂O emissions. In addition to the favorable economic impact, increasing N availability in the soil through minimizing nitrification by NI may reduce detrimental environmental consequences on water resources and greenhouse gas emissions. In agriculture, nitrogen fertilizer does not effectively absorb by plants. Several biological activities in the soil convert N into various compounds. Nitrogen oxide (N₂O) is an influential greenhouse gas formed in soils due to nitrification and denitrification process. Nitrapyrin (NI) combined with ammonium (NH₄⁺) based fertilizers is an effective technique for minimizing the N loss in agricultural soils by regulating ammonia-oxidizing. This research was conducted during 2019-2020 to determine the effect of NI on nitrogen emissions in soil and crop yield of wheat cultivars at three urea (UR) levels, NI+urea (NIU), and control (CO) on two cultivars (Rakhshan and Pishgam) and two tillage systems (No tillage (NT) and conventional tillage (CT)). The highest amounts of NH₄⁺, NO₃^- and N₂O were found at the stem elongation stage. While NIU fertilizer treatment yielded the highest NH₄⁺ (18.38 mg kg⁻¹), the UR fertilizer treatment yielded the highest NO₃^- (25.96 mg kg⁻¹) and N₂O (0.0192 kg N₂O-N ha⁻¹ day⁻¹). At all developmental stages in the CT and NT systems, the NIU treatment decreased the average nitrification of NH₄⁺ and its conversion to NO₃^- by 27.81 and 15.45%, respectively. Our findings, thus, showed that NI application in conjunction with UR could highly reduce N₂O emissions. In addition to the favorable economic impact, increasing N availability in the soil through minimizing nitrification by NI may reduce detrimental environmental consequences on water resources and greenhouse gas emissions. https://ijfcs.ut.ac.ir/article_92019_4ee2ada340a6edf748e155fb5552b77e.pdf