In a collaborative effort between the International Maize and Wheat Improvement Centre and the International Plant Nutrition Institute to test, pilot and upscale Nutrient Expert (NE; a decision support system)-based fertilizer management, on-farm participatory research was conducted in 7 districts (Karnal, Kurukshetra, Kaithal, Ambala, Sonepat, Panipat, and Yamunanager) of Haryana (India) to evaluate and compare the NE-based strategies in conventional and no-till wheat production systems. For this, 15 on-farm experiments were established in 2010-11 and 2011-12. The four nutrient management treatments included: (1) NE-based recommendation; (2) NE+GreenSeeker (GS; handheld sensors): NE recommendation supplemented with GS-guided application of N; (3) SR: state fertilizer recommendation; and (4) FFP or the farmers fertilizer application practice. These treatments were compared for agronomic productivity, economic profitability and total greenhouse gas emissions. Total greenhouse gas emissions from wheat production were estimated using the Cool Farm Tool. The results showed that both grain yield and net return were higher with NE-based strategies compared to FFP and SR. The estimated total carbon footprint (i.e. GWP per tonne of wheat grain production and per US$ of net return) was also lower for NE-based strategies than other nutrient management strategies. Thus, the use of precision nutrient management tools such as NE and GS are important for increasing wheat yields and farmer profits yet minimizing the environmental footprint of wheat production.
