Variability for Nitrogen Management in Genetically-Distant Maize (<em>Zea mays</em> L.) Lines: Impact of Post-Silking Nitrogen Limiting Conditions

• Main Authors: Isabelle Quilleré, Céline Dargel-Graffin, Peter J. Lea, Bertrand Hirel
• Format: Article
• Language: English
• Published: MDPI AG 2018-12-01
• Series: Agronomy
• Subjects: genetic diversity; maize; nitrogen; remobilization; silking; uptake; 15N-labeling
• Online Access: https://www.mdpi.com/2073-4395/8/12/309

The impact of nitrogen (N)-limiting conditions after silking on kernel yield (KY)-related traits and whole plant N management was investigated using fifteen maize lines representative of plant genetic diversity in Europe and America. A large level of genetic variability of these traits was observed in the different lines when post-silking fertilization of N was strongly reduced. Under such N-fertilization conditions, four different groups of lines were identified on the basis of KY and kernel N content. Although the pattern of N management, including N uptake and N use was variable in the four groups of lines, a number of them were able to maintain both a high yield and a high kernel N content by increasing shoot N remobilization. No obvious relationship between the genetic background of the lines and their mode of N management was found. When N was limiting after silking, N remobilization appeared to be a good predictive marker for identifying maize lines that were able to maintain a high yield and a high kernel N content irrespective of their female flowering date. The use of N remobilization as a trait to select maize genotypes adapted to low N input is discussed.