Mapping Quantitative Trait Loci for Yield Potential Traits in Wheat Recombinant Inbred Lines

Abstract

Selecting wheat with favorable spike characteristics has been a popular breeding strategy to improve sink capacity and yield potential. In the present study, quantitative trait loci (QTLs) for yield potential traits were identified using a recombinant inbred line (RIL) population derived from the cross between Taejoong and Keumkang, two Korean wheat cultivars. A linkage map encompassing a total genetic length of 6544.8 cM was constructed using 838 single nucleotide polymorphisms from the 35K Axiom Wheat Breeder’s Array. We detected eight QTLs for four yield potential traits that are consistently identified in at least two of the three environments, that is, one for days to heading date (QDHD-1 on chromosome 7B), three for spike length (QSL-1, QSL-2, and QSL-3 on chromosomes 1D, 5A, and 6A, respectively), one for tiller number (QTN-1 on chromosome 5B), and three for length of center rachis (QLCR-1, QLCR-2, and QLCR-3 on chromosomes 1B, 5B, and 6A, respectively). Notably, Taejoong contributed the alleles for long spike at all three spike length QTLs with the additive effects of 0.6 cm, 0.6 cm, and 0.9 cm at QSL-1, QSL-2, and QSL-3, respectively. No significant two-way or three-way interaction was observed among QSL-1, QSL-2, and QSL-3, indicating that pyramiding the Taejoong alleles at the three QTLs can increase spike length additively. While the Taejoong alleles at QSL-1, QSL-2, and QSL-3 were associated with increased days to heading date, more kernels per spike, and reduced tiller number per plant, the extent of the pleiotropic effects were different among the three QTLs. Due to the limited number of molecular markers and mapping resolution, further work is required to narrow down the identified QTLs and characterize their effects more precisely. Our results would provide useful information for modulating spike characteristics and improving yield potential in wheat breeding programs.

Genome-wide association study for grain yield and component traits in bread wheat (Triticum aestivum L.)

“…genome-wide association studies (GWAS) and quantitative trait loci (QTL) mapping are widely used methods to dissect the genetic basis of complex quantitative traits in crop plants. In the past decade, extensive efforts have been made to identify QTLs associated with grain yield and its component traits (Gao et al, 2015;Zhang et al, 2016;Jin et al, 2020;Isham et al, 2021;Kang et al, 2021;Li et al, 2022) in wheat through bi-parental populations based QTL mapping. Conventional QTL mapping mainly depends on structured populations like recombinant inbred lines (RIL), back-crosses (BC), and doubled haploids (DH).…”

Genome-wide association mapping in elite winter wheat breeding for yield improvement

“…Two main approaches to dissecting the genetic basis of complex quantitative traits in crop plants are genome-wide association studies (GWAS) and quantitative trait loci (QTL) mapping. Many QTLs associated with yield-related traits in bread wheat have been identified in biparental populations (Jin et al 2020 ; Isham et al 2021 ; Kang et al 2021 ; Li et al 2022 ). At present, GWAS has become more frequently used as it allows for the identification of parts of the complex, essential traits valid in a studied panel of genotypes (Neumann et al 2011 ; Sukumaran et al 2018 ; Liu et al 2018 ; Garcia et al 2019 ; Qaseem et al 2019 ; Sheoran et al 2019 ; Akram et al 2021 ).…”

Genome-wide association mapping in elite winter wheat breeding for yield improvement

“…Two main approaches to dissect the genetic basis of complex quantitative traits in crop plants are genome-wide association studies (GWAS) and quantitative trait loci (QTL) mapping. Many QTLs associated with yield-related traits in bread wheat have been identified in biparental populations (Gao et al 2015;Yu et al 2017;Milner et al, 2016;Zhang et al 2016;Jin et al 2020;Isham et al 2021;Kang et al 2021;Li et al 2022). At present, GWAS has become more frequently used as it allows to identify of parts of the complex, essential traits valid in a studied panel of genotypes (Breseghello and Sorrells 2006;Neumann et al 2011;Dodig et al 2012;Jiang et al 2015;Liu et al 2015;Hu et al 2015;Sukumaran et al 2015;Sukumaran et al 2018;Tadesse et al 2015;Lozada et al 2017;Sun et al 2017;Würschum et al 2017b;Bhatta et al 2018;Sheoran et al 2019;Sun et al 2017;Liu et al 2018;Akram et al 2021;Qaseem et al 2019;Garcia et al 2019).…”