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Theoretical and Applied Genetics

, Volume 126, Issue 10, pp 2587–2596 | Cite as

Genome-wide association analysis for nine agronomic traits in maize under well-watered and water-stressed conditions

  • Yadong Xue
  • Marilyn L. Warburton
  • Mark Sawkins
  • Xuehai Zhang
  • Tim Setter
  • Yunbi Xu
  • Pichet Grudloyma
  • James Gethi
  • Jean-Marcel Ribaut
  • Wanchen Li
  • Xiaobo Zhang
  • Yonglian Zheng
  • Jianbing Yan
Original Paper

Abstract

Drought can cause severe reduction in maize production, and strongly threatens crop yields. To dissect this complex trait and identify superior alleles, 350 tropical and subtropical maize inbred lines were genotyped using a 1536-SNP array developed from drought-related genes and an array of 56,110 random SNPs. The inbred lines were crossed with a common tester, CML312, and the testcrosses were phenotyped for nine traits under well-watered and water-stressed conditions in seven environments. Using genome-wide association mapping with correction for population structure, 42 associated SNPs (P ≤ 2.25 × 10−6 0.1/N) were identified, located in 33 genes for 126 trait × environment × treatment combinations. Of these genes, three were co-localized to drought-related QTL regions. Gene GRMZM2G125777 was strongly associated with ear relative position, hundred kernel weight and timing of male and female flowering, and encodes NAC domain-containing protein 2, a transcription factor expressed in different tissues. These results provide some good information for understanding the genetic basis for drought tolerance and further studies on identified candidate genes should illuminate mechanisms of drought tolerance and provide tools for designing drought-tolerant maize cultivars tailored to different environmental scenarios.

Keywords

Quantitative Trait Locus Drought Tolerance Hundred Kernel Weight Grain Yield Maize Inbred Line 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

This research was supported by the Generation Challenge Program and the National Hi-Tech Research and Development Program of China (2012AA10A307) and the National Natural Science Foundation of China (31101156).

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Yadong Xue
    • 1
  • Marilyn L. Warburton
    • 2
  • Mark Sawkins
    • 3
  • Xuehai Zhang
    • 1
  • Tim Setter
    • 4
  • Yunbi Xu
    • 5
  • Pichet Grudloyma
    • 6
  • James Gethi
    • 7
  • Jean-Marcel Ribaut
    • 3
  • Wanchen Li
    • 8
  • Xiaobo Zhang
    • 1
  • Yonglian Zheng
    • 1
  • Jianbing Yan
    • 1
  1. 1.National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanChina
  2. 2.USDA-ARS Corn Host Plant Research Resistance UnitMississippi State UniversityStarkvilleUSA
  3. 3.Generation Challenge ProgramMexico, D.F.Mexico
  4. 4.Department of Crop and Soil SciencesCornell UniversityIthacaUSA
  5. 5.International Maize and Wheat Improvement CenterMexico, D.F.Mexico
  6. 6.Nakhon Sawan Field Crops Research Center (NSFCRC)TakfaThailand
  7. 7.Kenya Agricultural Research Institute (KARI)MtwapaKenya
  8. 8.Maize Research InstituteSichuan Agricultural UniversityYa’anChina

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