Theoretical and Applied Genetics

, Volume 119, Issue 5, pp 913–930

Drought stress and tropical maize: QTL-by-environment interactions and stability of QTLs across environments for yield components and secondary traits

  • Rainer Messmer
  • Yvan Fracheboud
  • Marianne Bänziger
  • Mateo Vargas
  • Peter Stamp
  • Jean-Marcel Ribaut
Original Paper

DOI: 10.1007/s00122-009-1099-x

Cite this article as:
Messmer, R., Fracheboud, Y., Bänziger, M. et al. Theor Appl Genet (2009) 119: 913. doi:10.1007/s00122-009-1099-x

Abstract

A recombinant inbred line (RIL) population was evaluated in seven field experiments representing four environments: water stress at flowering (WS) and well-watered (WW) conditions in Mexico and Zimbabwe. The QTLs were identified for each trait in each individual experiment (single-experiment analysis) as well as per environment, per water regime across locations and across all experiments (joint analyses). For the six target traits (male flowering, anthesis-to-silking interval, grain yield, kernel number, 100-kernel fresh weight and plant height) 81, 57, 51 and 34 QTLs were identified in the four step-wise analyses, respectively. Despite high values of heritability, the phenotypic variance explained by QTLs was reduced, indicating epistatic interactions. About 80, 60 and 6% of the QTLs did not present significant QTL-by-environment interactions (QTL × E) in the joint analyses per environment, per water regime and across all experiments. The expression of QTLs was quite stable across years at a given location and across locations under the same water regime. However, the stability of QTLs decreased drastically when data were combined across water regimes, reflecting a different genetic basis of the target traits in the drought and well-watered trials. Several clusters of QTLs for different traits were identified by the joint analyses of the WW (chromosomes 1 and 8) and WS (chromosomes 1, 3 and 5) treatments and across water regimes (chromosome 1). Those regions are clear targets for future marker-assisted breeding, and our results confirm that the best approach to breeding for drought tolerance includes selection under water stress.

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Rainer Messmer
    • 1
  • Yvan Fracheboud
    • 1
  • Marianne Bänziger
    • 2
  • Mateo Vargas
    • 3
  • Peter Stamp
    • 1
  • Jean-Marcel Ribaut
    • 4
  1. 1.ETH Zurich, Institute of Plant SciencesZurichSwitzerland
  2. 2.International Maize and Wheat Improvement Center (CIMMYT)NairobiKenya
  3. 3.International Maize and Wheat Improvement Center (CIMMYT)MexicoMexico
  4. 4.Generation Challenge ProgrammeInternational Maize and Wheat Improvement Center (CIMMYT)MexicoMexico