Theoretical and Applied Genetics

, Volume 113, Issue 6, pp 1131–1146

A simplified conceptual model of carbon/nitrogen functioning for QTL analysis of winter wheat adaptation to nitrogen deficiency

Authors

    • UMR INRA-INA PG Environnement et Grandes Cultures
    • INRA, Unité de Génétique et d’Amélioration des Plantes
  • F. Devienne-Barret
    • UMR INRA-INA PG Environnement et Grandes Cultures
  • O. Maury
    • UMR INRA-INA PG Environnement et Grandes Cultures
  • J. Le Gouis
    • INRA, Unité de Génétique et d’Amélioration des Plantes
  • B. Ney
    • UMR INRA-INA PG Environnement et Grandes Cultures
Original Paper

DOI: 10.1007/s00122-006-0373-4

Cite this article as:
Laperche, A., Devienne-Barret, F., Maury, O. et al. Theor Appl Genet (2006) 113: 1131. doi:10.1007/s00122-006-0373-4

Abstract

Breeding new varieties adapted to low-input agricultural practices is of particular interest in light of current economical and environmental concerns. Improving nitrogen (N) uptake and N utilization efficiency (NUE) are two ways of producing varieties tolerant to low N input. To offer new possibilities to breeders, it is necessary to acquire more knowledge about these two processes. Knowing C and N metabolisms are linked and knowing N uptake is partly explained by root characteristics, we carried out a QTL analysis for traits associated with N uptake and NUE by using both a conceptual model of C/N plant functioning and a root architecture description. A total of 120 lines were selected according to their genotype among 241 doubled haploids derived from two varieties, one N stress tolerant and the other N stress sensitive. They were grown in hydroponic rhizotrons under N-limited nutritional conditions. Initial conditions varied among genotypes; therefore, total root length on day 1 was used to correct traits. Heritabilities ranged from 13 to 84%. Thirty-two QTL were located: 6 associated with root architecture (on chromosomes 4B, 5A, 5D and 7B), 6 associated with model efficiencies (1B, 2B, 6A, 6B, 7A, 7B and 7D) and 20 associated with state variables (1A, 1B, 2B, 4B, 5A, 5B and 6B). The effects of the dwarfing gene Rht-B1 on root traits are discussed, as well as the features of a conceptual plant functioning model, as a useful tool to assess pertinent traits for QTL detection. It is suggested that further studies that couple QTL with a functioning model and a root architecture description could serve in the search for ideotypes.

Abbreviations

ADM

Aerial dry matter

DH

Doubled haploids

h2

Heritability

LA

Leaf area

LG

Linkage group

LRL

Lateral root length

LRN

Lateral root number

N

Nitrogen

NcAP

Aerial parts nitrogen content

NcR

Root nitrogen content

NTOT

Amount of total nitrogen

NUR

Nitrogen-specific uptake rate

PAR

Photosynthetically active radiation

PRL

Primary root length

QTL

Quantitative trait locus

RDM

Root dry matter

SRL

Specific root length

SSR

Simple sequence repeats

TDM

Total dry matter

TRL

Total root length

RUE

Radiation use efficiency

Copyright information

© Springer-Verlag 2006