Abstract
BackgroundGlutenin contents and compositions are crucial factors influencing the end-use quality of wheat. Although the composition of glutenin fractions is well known, there has been relatively little research on the genetic basis of glutenin fractions in wheat.ResultsTo elucidate the genetic basis for the contents of glutenin and its fractions, a population comprising 196 recombinant inbred lines (RILs) was constructed from two parents, Luozhen No.1 and Zhengyumai 9987, which differ regarding their total glutenin and its fraction contents (except for the By fraction). Forty-one additive Quantitative Trait Loci (QTL) were detected in four environments over two years. These QTL explained 1.3% - 53.4% of the phenotypic variation in the examined traits. Forty-three pairs of epistatic QTL (E-QTL) were detected in the RIL population across four environments. The QTL controlling the content of total glutenin and its seven fractions were detected in clusters. Seven clusters enriched with QTL for more than three traits were identified, including a QTL cluster 6AS-3, which was revealed as a novel genetic locus for glutenin and related traits. Kompetitive Allele-Specific PCR (KASP) markers developed from the main QTL cluster 1DL-2 and the previously developed KASP marker for the QTL cluster 6AS-3 were validated as significantly associated with the target traits in the RIL population and in natural varieties.ConclusionsThis study identified novel genetic loci related to glutenin and its seven fractions. Additionally, the developed KASP markers may be useful for the marker-assisted selection of varieties with high glutenin fraction content and for identifying individuals in the early developmental stages without the need for phenotyping mature plants. On the basis of the results of this study and the KASP markers described herein, breeders will be able to efficiently select wheat lines with favorable glutenin properties and develop elite lines with high glutenin subunit contents.
Highlights
Glutenin contents and compositions are crucial factors influencing the end-use quality of wheat
Phenotypic variation and genetic effects of the parents and recombinant inbred lines (RILs) The contents of total glutenin and its seven fractions Ax, Bx, By, Dx, Dy, High Molecular Weight Subunits (HMW-GS) and Low Molecular Weight Subunits (LMW-GS) were investigated in the parents and the RIL population under four environments (Table S1)
The Ax, Bx, Dx, Dy and HMW-GS contents differed at the P < 0.01 level, whereas LMW-GS and total glutenin contents differed at the P < 0.05 level (Fig. 1 and Table 1)
Summary
Glutenin contents and compositions are crucial factors influencing the end-use quality of wheat. Glutenins consist of high- and low-molecular-weight subunits (HMW-GS and LMW-GS), which are linked by disulfide bonds to form polymeric proteins in wheat [1]. The HMW-GS content is highly associated with dough viscoelasticity and bread-baking quality, despite only accounting for only about 7%-15% of the total protein in flour [2]. HMW-GSs are encoded by three homologous loci located on the long arm of chromosome 1 in each genome (Glu-A1, Glu-B1 and Glu-D1) which contribute two tightly linked genes for x- and y- type subunits that are distinguished by molecular weights and the conserved N~terminal domain sequences [3, 4]. The genetic loci related to LMW-GSs are GluA3, Glu-B3 and Glu-D3, which are located on the short arm of chromosome 1. In addition to these homologous loci, three new loci, Glu-2, Glu-4 and Glu-5, have been identified on chromosomes 1B, 1D and 7D, respectively [6, 7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
