Evolution of US maize (Zea mays L.) root architectural and anatomical phenes over the past 100 years corresponds to increased tolerance of nitrogen stress

© The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Bibliographische Detailangaben
Veröffentlicht in:Journal of experimental botany. - 1985. - 66(2015), 8 vom: 27. Apr., Seite 2347-58
1. Verfasser: York, Larry M (VerfasserIn)
Weitere Verfasser: Galindo-Castañeda, Tania, Schussler, Jeffrey R, Lynch, Jonathan P
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2015
Zugriff auf das übergeordnete Werk:Journal of experimental botany
Schlagworte:Journal Article Research Support, U.S. Gov't, Non-P.H.S. Anatomy architecture density maize nitrogen phenotype root. Nitrogen N762921K75
Beschreibung
Zusammenfassung:© The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Increasing the nitrogen use efficiency of maize is an important goal for food security and agricultural sustainability. In the past 100 years, maize breeding has focused on yield and above-ground phenes. Over this period, maize cultivation has changed from low fertilizer inputs and low population densities to intensive fertilization and dense populations. The authors hypothesized that through indirect selection the maize root system has evolved phenotypes suited to more intense competition for nitrogen. Sixteen maize varieties representing commercially successful lines over the past century were planted at two nitrogen levels and three planting densities. Root systems of the most recent material were 7 º more shallow, had one less nodal root per whorl, had double the distance from nodal root emergence to lateral branching, and had 14% more metaxylem vessels, but total mextaxylem vessel area remained unchanged because individual metaxylem vessels had 12% less area. Plasticity was also observed in cortical phenes such as aerenchyma, which increased at greater population densities. Simulation modelling with SimRoot demonstrated that even these relatively small changes in root architecture and anatomy could increase maize shoot growth by 16% in a high density and high nitrogen environment. The authors concluded that evolution of maize root phenotypes over the past century is consistent with increasing nitrogen use efficiency. Introgression of more contrasting root phene states into the germplasm of elite maize and determination of the functional utility of these phene states in multiple agronomic conditions could contribute to future yield gains
Beschreibung:Date Completed 20.01.2016
Date Revised 24.03.2024
published: Print-Electronic
Citation Status MEDLINE
ISSN:1460-2431
DOI:10.1093/jxb/erv074