Post-silking carbon partitioning under nitrogen deficiency revealed sink limitation of grain yield in maize
Maize (Zea mays) plants exhibit altered carbon partitioning under nitrogen (N) deficiency, but the mechanisms by which N availability affects sugar export out of leaves and transport into developing ears remain unclear. Maize was grown under field conditions with different N supply. Plant growth, su...
Veröffentlicht in: | Journal of experimental botany. - 1985. - 69(2018), 7 vom: 24. März, Seite 1707-1719 |
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1. Verfasser: | |
Weitere Verfasser: | , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2018
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Zugriff auf das übergeordnete Werk: | Journal of experimental botany |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Sugars Carbon 7440-44-0 Nitrogen N762921K75 |
Zusammenfassung: | Maize (Zea mays) plants exhibit altered carbon partitioning under nitrogen (N) deficiency, but the mechanisms by which N availability affects sugar export out of leaves and transport into developing ears remain unclear. Maize was grown under field conditions with different N supply. Plant growth, sugar movement, and starch turnover in source or sink tissues were investigated at silking and 20 or 21 days after silking. Nitrogen deficiency stunted plant growth and grain yield compared with N-sufficient plants, and resulted in greater starch concentrations in leaves due to more as well as larger starch granules in bundle sheath cells. Transmission electron microscopy revealed an open symplastic pathway for sucrose movement in N-deficient leaves, while the expression levels of transporters responsible for sucrose efflux and phloem loading were lower than in N-sufficient leaves. Nonetheless, greater starch concentrations in the apical cob portion of N-deficient plants implied sufficient carbon supply relative to the diminished sink strength (decreased kernel number and weight). Together with the high sugar concentrations in the developing kernels, the results indicated that reduced sink capacity and sugar utilization during grain filling may limit the yield in N-deficient plants, which in turn imposes a feedback inhibition on sugar export from leaves |
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Beschreibung: | Date Completed 15.10.2019 Date Revised 15.10.2019 published: Print Citation Status MEDLINE |
ISSN: | 1460-2431 |
DOI: | 10.1093/jxb/erx496 |