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A novel QTL QTrl.saw-2D.2 associated with the total root length identified by linkage and association analyses in wheat (Triticum aestivum L.)

Planta volume 250, pages 129–143 (2019)Cite this article

Abstract

Main conclusion

In wheat, a QTL QTrl.saw-2D.2 associated with the total root length was identified, presumably containing genes closely related to root development.

A mapping population of 184 recombinant inbred lines derived from the cross SY95-71 × CH7034 was used to map QTL for seedling root characteristics in hydroponic culture (HC) and in soil-filled pot (SP) methods. Four traits, including maximum root length (MRL), root number (RN), total length (TRL), and root diameter (RD) were measured and used in QTL analyses. A total of 33 QTL for the four root traits were detected, 17 QTLs for TRL, six for RN, seven for MRL, and three for RD. Seven QTL were detected in both HC and SP methods, which explained 7–18% phenotypic variation. One QTL QTrl.saw-2D.2 detected in both HC and SP methods was also validated in another population comprised of 215 diverse lines. This QTL is a novel QTL that explained the highest phenotypic variation 18% in all QTL identified in the present study. Based on candidate gene and comparative genomics analyses, the QTL QTrl.saw-2D.2 may contain genes closely related to root development in wheat (Triticum aestivum L.). The two candidate genes were proposed to explore in future studies.

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Abbreviations

DL:

Dryland conditions

DTC:

Drought tolerance coefficient

HC:

Hydroponic culture

KNS:

Kernel number per spike

MRL:

Maximum root length

RD:

Root diameter

RIL:

Recombinant inbred line

RN:

Root number

SL:

Spike length

SN:

Spikelet number per spike

SP:

Pots containing soil

TKW:

Thousand kernel weight

TRL:

Total root length

WW:

Well-watered condition

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Acknowledgements

This work was funded by National Key Research and Development Program of China (2017YFD0100600), Agricultural Science and Technology Project (YCX2018413, 17yzgc010), Natural Science Foundation of Shanxi Province (2016011001, 201703D211007). We thank Dr. Robert A McIntosh (University of Sydney) for help with manuscript improvement.

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Affiliations

  1. Institute of Wheat Research, Shanxi Academy of Agricultural Sciences, Linfen, China

    Xingwei Zheng, Ling Qiao, Jiajia Zhao & Jun Zheng

  2. Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China

    Xiaojie Wen

  3. The Shanxi Province Key Laboratory of Crop Genetics and Gene Improvement, Institute of Crop Science, Shanxi Academy of Agricultural Sciences, Taiyuan, Shanxi, China

    Xiaojun Zhang, Xin Li, Shuwei Zhang, Zujun Yang & Zhijian Chang

  4. Department of Plant Sciences, University of Idaho, Aberdeen, ID, USA

    Jianli Chen

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  1. Xingwei Zheng
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Zheng, X., Wen, X., Qiao, L. et al. A novel QTL QTrl.saw-2D.2 associated with the total root length identified by linkage and association analyses in wheat (Triticum aestivum L.). Planta 250, 129–143 (2019). https://doi.org/10.1007/s00425-019-03154-x

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Keywords

  • Drought tolerance coefficient
  • Quantitative trait locus
  • Stay green
  • Total root length
  • Yield components