caa a22 4500 606219668 CHVBK 20210128101119.0 cr unu---uuuuu 210128e20150101xx s 000 0 eng 10.1007/s11104-014-2182-x doi (NATIONALLICENCE)springer-10.1007/s11104-014-2182-x Modelling the relative contribution of seed nitrogen reserves and external nitrogen uptake during heterotrophic growth in Medicago truncatula [Elektronische Daten] [Sophie Brunel-Muguet, Bruno Mary, Carolyne Dürr] Background and aims: Heterotrophic growth relies on remobilisation of seed reserves and mineral absorption. We used a compartmental model to investigate the fluxes of N absorption and remobilisation of N reserves in a legume seed with high protein content. Methods: Seedling growth was studied during the heterotrophic stage in two genotypes of Medicago truncatula as a function of N supply. N absorption and seed remobilisation fluxes were distinguished in a 15 N labelling experiment. Results: Remobilisation of seed N reserves was high during germination, but N uptake started as soon as the radicle protruded. Both sources contributed to high elongation rates of the radicle and hypocotyl. When organ lengths stabilised, there was an efflux of N from the cotyledons and roots indicating that seedling growth was limited by carbohydrate production. No significant differences between genotypes were observed except for early N uptake, which was lower in the genotype with the highest initial seed N content. Conclusions: N fluxes were similar to those of other non-legume dicotyledonous species but differed from monocotyledonous species. These results improve our understanding of the effects of mineral fertilisation on crop establishment. The compartmental model is a useful tool to analyse N fluxes patterns within and between diverse species, in relation to seed characteristics and soil N availability. Springer International Publishing Switzerland, 2014 Nitrogen nationallicence Seedling nationallicence Absorption nationallicence Remobilization nationallicence Compartment model nationallicence Medicago truncatula nationallicence Brunel-Muguet Sophie INRA UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, F-14032, Caen, France aut Mary Bruno INRA UR Agro-Impact, Pôle du Griffon, F-02000, Barenton-Bugny, France aut Dürr Carolyne INRA UMR 1345 Institute of Research on Horticulture and seeds, F-49045, Beaucouzé, France aut Plant and Soil Springer International Publishing 386/1-2(2015-01-01), 331-340 0032-079X 386:1-2<331 2015 386 11104 https://doi.org/10.1007/s11104-014-2182-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11104-014-2182-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Brunel-Muguet Sophie INRA UMR 950 Ecophysiologie Végétale, Agronomie et nutritions N, C, S, F-14032, Caen, France aut NATIONALLICENCE 700 1- Mary Bruno INRA UR Agro-Impact, Pôle du Griffon, F-02000, Barenton-Bugny, France aut NATIONALLICENCE 700 1- Dürr Carolyne INRA UMR 1345 Institute of Research on Horticulture and seeds, F-49045, Beaucouzé, France aut NATIONALLICENCE 773 0- Plant and Soil Springer International Publishing 386/1-2(2015-01-01), 331-340 0032-079X 386:1-2<331 2015 386 11104