Mining Aegilops tauschii genetic diversity in the background of bread wheat revealed a novel QTL for seed dormancy

Monir Idres Yahya Ahmed; Yasir Serag Alnor Gorafi; Nasrein Mohamed Kamal; Mohammed Yousif Balla; Izzat Sidahmed Ali Tahir; Lipeng Zheng; Naoto Kawakami; Hisashi Tsujimoto

doi:10.3389/fpls.2023.1270925

Mining Aegilops tauschii genetic diversity in the background of bread wheat revealed a novel QTL for seed dormancy

Front Plant Sci. 2023 Nov 30:14:1270925. doi: 10.3389/fpls.2023.1270925. eCollection 2023.

Authors

Affiliations

¹ United Graduate School of Agricultural Sciences, Tottori University, Tottori, Japan.
² International Platform for Dryland Research and Education, Tottori University, Tottori, Japan.
³ Gezira Research Station, Agricultural Research Corporation (ARC), Wad-Medani, Sudan.
⁴ Arid Land Research Center, Tottori University, Tottori, Japan.
⁵ Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki, Japan.

Abstract

Due to the low genetic diversity in the current wheat germplasm, gene mining from wild relatives is essential to develop new wheat cultivars that are more resilient to the changing climate. Aegilops tauschii, the D-genome donor of bread wheat, is a great gene source for wheat breeding; however, identifying suitable genes from Ae. tauschii is challenging due to the different morphology and the wide intra-specific variation within the species. In this study, we developed a platform for the systematic evaluation of Ae. tauschii traits in the background of the hexaploid wheat cultivar 'Norin 61' and thus for the identification of QTLs and genes. To validate our platform, we analyzed the seed dormancy trait that confers resistance to preharvest sprouting. We used a multiple synthetic derivative (MSD) population containing a genetic diversity of 43 Ae. tauschii accessions representing the full range of the species. Our results showed that only nine accessions in the population provided seed dormancy, and KU-2039 from Afghanistan had the highest level of seed dormancy. Therefore, 166 backcross inbred lines (BILs) were developed by crossing the synthetic wheat derived from KU-2039 with 'Norin 61' as the recurrent parent. The QTL mapping revealed one novel QTL, Qsd.alrc.5D, associated with dormancy explaining 41.7% of the phenotypic variation and other five unstable QTLs, two of which have already been reported. The Qsd.alrc.5D, identified for the first time within the natural variation of wheat, would be a valuable contribution to breeding after appropriate validation. The proposed platform that used the MSD population derived from the diverse Ae. tauschii gene pool and recombinant inbred lines proved to be a valuable platform for mining new and important QTLs or alleles, such as the novel seed dormancy QTL identified here. Likewise, such a platform harboring genetic diversity from wheat wild relatives could be a useful source for mining agronomically important traits, especially in the era of climate change and the narrow genetic diversity within the current wheat germplasm.

Keywords: Aegilops tauschii; QTL analysis; bread wheat; gene mining; germplasm enhancement; seed dormancy.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was funded by the Science and Technology Research Partnership for Sustainable Development (SATREPS) grant JPMJSA1805 by Japan Science and Technology Agency.