Modelling postsilking nitrogen fluxes in maize (Zea mays) using 15N-labelling field experiments
Article first published online: 27 SEP 2006
Volume 172, Issue 4, pages 696–707, December 2006
How to Cite
Gallais, A., Coque, M., Quilléré, I., Prioul, J.-L. and Hirel, B. (2006), Modelling postsilking nitrogen fluxes in maize (Zea mays) using 15N-labelling field experiments. New Phytologist, 172: 696–707. doi: 10.1111/j.1469-8137.2006.01890.x
- Issue published online: 27 SEP 2006
- Article first published online: 27 SEP 2006
- Received: 30 June 2006 Accepted: 7 August 2006
- maize (Zea mays);
- 15N labelling;
- nitrogen remobilization;
- nitrogen uptake;
- nitrogen use efficiency;
- protein turnover
- • In maize (Zea mays), nitrogen (N) remobilization and postflowering N uptake are two processes that provide amino acids for grain protein synthesis.
- • To study the way in which N is allocated to the grain and to the stover, two different 15N-labelling techniques were developed. 15NO3− was provided to the soil either at the beginning of stem elongation or after silking. The distribution of 15N in the stover and in the grain was monitored by calculating relative 15N-specific allocation (RSA).
- • A nearly linear relationship between the RSA of the kernels and the RSA of the stover was found as a result of two simultaneous N fluxes: N remobilization from the stover to the grain, and N allocation to the stover and to the grain originating from N uptake.
- • By modelling the 15N fluxes, it was possible to demonstrate that, as a consequence of protein turnover, a large proportion of the amino acids synthesized from the N taken up after silking were integrated into the proteins of the stover, and these proteins were further hydrolysed to provide N to the grain.