145722 20260217205604.0 doi 10.1093/jxb/erae382 sideral 140633 ART-2024-140633 eng De la Peña, Marlon Natural variation in the adjustment of primary metabolism determines ammonium tolerance in the model grass Brachypodium distachyon 2024 Access copy available to the general public Unrestricted Nitrogen (N) fertilization is essential to maximize crop production. However, around half of the applied N is lost to the environment, causing water and air pollution and contributing to climate change. Understanding the natural genetic and metabolic basis underlying plants N use efficiency is of great interest to attain an agriculture with less N demand and thus more sustainable. The study of ammonium (NH4+) nutrition is of particular interest, because it mitigates N losses due to nitrate (NO3–) leaching or denitrification. In this work, we studied Brachypodium distachyon, the model plant for C3 grasses, grown with NH4+ or NO3– supply. We performed gene expression analysis in the root of the B. distachyon reference accession Bd21 and examined the phenotypic variation across 52 natural accessions through analyzing plant growth and a panel of 22 metabolic traits in leaf and root. We found that the adjustment of primary metabolism to NH4+ nutrition is essential for the natural variation of NH4+ tolerance, notably involving NH4+ assimilation and phosphoenolpyruvate carboxylase (PEPC) activity. Additionally, genome-wide association studies (GWAS) indicated several loci associated with B. distachyon growth and metabolic adaptation to NH4+ nutrition. We found that the GDH2 gene was associated with the induction of root glutamate dehydrogenase activity under NH4+ nutrition and that two genes encoding malic enzyme were associated with leaf PEPC activity. Altogether, our work underlines the value of natural variation and the key role of primary metabolism to improve NH4+ tolerance. info:eu-repo/grantAgreement/ES/MICINN/PID2020-113385RB-I00 info:eu-repo/semantics/openAccess by-nc-nd https://creativecommons.org/licenses/by-nc-nd/4.0/deed.es 5.7 2024 PLANT SCIENCES 24 / 273 = 0.088 2024 Q1 T1 1.778 2024 Plant Science 2024 Q1 Physiology 2024 Q1 11.7 2024 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Poucet, Théo Montardit-Tarda, Francesc Urmeneta, Leyre Urbano-Gámez, Jose Alberto Cassan, Cédric Vega-Mas, Izargi Catalán, Pilar Universidad de Zaragoza (orcid)0000-0001-7793-5259 Igartua, Ernesto Gibon, Yves Gonzalez-Moro, M Begoña Marino, Daniel 5011 063 Universidad de Zaragoza Dpto. CC.Agrar.y Medio Natural Área Botánica 75, 22 (2024), 7237–7253 J. Exp. Bot. Journal of Experimental Botany 0022-0957 4386462 http://zaguan.unizar.es/record/145722/files/texto_completo.pdf Versión publicada 2843584 http://zaguan.unizar.es/record/145722/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:145722 articulos driver 2026-02-17-20:46:19 ARTICLE