The new nitrification inhibitor 3,4-dimethylpyrazole succinic (DMPSA) as an alternative to DMPP for reducing N2O emissions from wheat crops under humid Mediterranean conditions

• Published in: European journal of agronomy 2016-10, Vol.80, p.78-87
• Main Authors: Huérfano, Ximena, Fuertes-Mendizábal, Teresa, Fernández-Diez, Kevin, Estavillo, José María, González-Murua, Carmen, Menéndez, Sergio
• Format: Article
• Language: English
• Subjects: agricultural soils; ammonium sulfate; Ammonium sulphate; carbon dioxide; crops; Denitrification; grain protein; grain yield; greenhouse gas emissions; Greenhouse gases; methane; nitrification; nitrification inhibitors; nitrogen fertilizers; nitrous oxide; soil water; soil water content; Stem-elongation; temperature; Tillering; WFPS; wheat; yield components
• ISSN: 1161-0301; 1873-7331
• DOI: 10.1016/j.eja.2016.07.001

•The DMPSA reduces N2O emissions without affecting yield and its components.•DMPSA and DMPP don’t show differences on daily N2O fluxes and grain yield.•Neither nitrification inhibitors affect to CO2 and CH4 emissions. Nowadays agricultural practices are based in the use of N fertilizers which can lead to environmental N losses. These losses can occur as nitrous oxide (N2O) emissions as result of the microbial processes of nitrification and denitrification. N2O together with carbon dioxide (CO2) and methane (CH4) are the strongest greenhouse gases (GHG) associated with agricultural soils. Nitrification inhibitors (NI) have been developed with the aim of decreasing fertilizer-induced N losses and increasing N efficiency. One of the most popular NI is the 3,4-dimethylpyrazol phosphate (DMPP) which have proven to be an advisable strategy to mitigate GHG emissions while maintaining crops yield. A new NI, 3,4-dimethylpyrazole succinic (DMPSA), has been developed. The objective of this study was to compare the impact of the new nitrification inhibitor DMPSA on greenhouse gases emissions, wheat yield and grain protein with respect to DMPP. For this purpose a field-experiment was carried out for two years. Fertilizer dose, with and without NIs, was 180kgNha−1 applied as ammonium sulphate (AS) split in two applications of 60kgNha−1 and 120kgNha−1, respectively. A single application of 180kgNha−1 of AS with NIs was also made. An unfertilized treatment was also included. The new nitrification inhibitor DMPSA reduces N2O emissions up to levels of the unfertilized control treatment maintaining the yield and its components. The DMPSA shows the same behavior as DMPP in relation to N2O fluxes, as well as wheat yield and quality. In spite of applying a double dose of N at stem elongation than at tillering, N2O losses from that period are lower than at tillering as a consequence of the influence of soil water content and temperature reducing the N2O/N2 ratio by denitrification. NI efficiency in reducing N2O losses is determined by the magnitude of the losses from the AS treatment.