Post-silking 15N labelling reveals an enhanced nitrogen allocation to leaves in modern maize (Zea mays) genotypes
Copyright © 2021 Elsevier GmbH. All rights reserved.
Veröffentlicht in: | Journal of plant physiology. - 1979. - 268(2022) vom: 01. Jan., Seite 153577 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2022
|
Zugriff auf das übergeordnete Werk: | Journal of plant physiology |
Schlagworte: | Journal Article (15)N labelling Allocation Maize Nitrogen Remobilization Uptake N762921K75 |
Zusammenfassung: | Copyright © 2021 Elsevier GmbH. All rights reserved. Nitrogen (N) metabolism is a major research target for increasing productivity in crop plants. In maize (Zea mays L.), yield gain over the last few decades has been associated with increased N absorption and utilization efficiency (i.e. grain biomass per unit of N absorbed). However, a dynamical framework is still needed to unravel the role of internal processes such as uptake, allocation, and translocation of N in these adaptations. This study aimed to 1) characterize how genetic enhancement in N efficiency conceals changes in allocation and translocation of N, and 2) quantify internal fluxes behind grain N sources in two historical genotypes under high and low N supply. The genotypes 3394 and P1197, landmark hybrids representing key eras of genetic improvement (1990s and 2010s), were grown under high and low N supply in a two-year field study. Using stable isotope 15N labelling, post-silking nitrogen fluxes were modeled through Bayesian estimation by considering the external N (exogenous-N) and the pre-existing N (endogenous-N) supply across plant organs. Regardless of N availability, P1197 exhibited greater exogenous-N accumulated in leaves and cob-husks. This response was translated to a larger amount of N mobilized to grains (as endogenous-N) during grain-filling in this genotype. Furthermore, the enhanced N supply to leaves in P1197 was associated with increased post-silking carbon accumulation. The overall findings suggest that increased N utilization efficiency over time in maize genotypes was associated with an increased allocation of N to leaves and subsequent translocation to the grains |
---|---|
Beschreibung: | Date Completed 17.01.2022 Date Revised 17.01.2022 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1618-1328 |
DOI: | 10.1016/j.jplph.2021.153577 |