A Major Quantitative Trait Loci Cluster Controlling Three Components of Yield and Plant Height Identified on Chromosome 4B of Common Wheat

Abstract

Wheat yield is not only affected by three components of yield, but also affected by plant height (PH). Identification and utilization of the quantitative trait loci (QTL) controlling these four traits is vitally important for breeding high-yielding wheat varieties. In this work, we conducted a QTL analysis using the recombinant inbred lines (RILs) derived from a cross between two winter wheat varieties of China, “Nongda981” (ND981) and “Nongda3097” (ND3097), exhibiting significant differences in spike number per unit area (SN), grain number per spike (GNS), thousand grain weight (TGW), and PH. A total of 11 environmentally stable QTL for these four traits were detected. Among them, four major and stable QTLs (QSn.cau-4B-1.1, QGns.cau-4B-1, QTgw.cau-4B-1.1, and QPh.cau-4B-1.2) explaining the highest phenotypic variance for SN, GNS, TGW, and PH, respectively, were mapped on the same genomic region of chromosome 4B and were considered a QTL cluster. The QTL cluster spanned a genetic distance of about 12.3 cM, corresponding to a physical distance of about 8.7 Mb. Then, the residual heterozygous line (RHL) was used for fine mapping of the QTL cluster. Finally, QSn.cau-4B-1.1, QGns.cau-4B-1, and QPh.cau-4B-1.2 were colocated to the physical interval of about 1.4 Mb containing 31 annotated high confidence genes. QTgw.cau-4B-1.1 was divided into two linked QTL with opposite effects. The elite NILs of the QTL cluster increased SN and PH by 55.71–74.82% and 14.73–23.54%, respectively, and increased GNS and TGW by 29.72–37.26% and 5.81–11.24% in two environments. Collectively, the QTL cluster for SN, GNS, TGW, and PH provides a theoretical basis for improving wheat yield, and the fine-mapping result will be beneficial for marker-assisted selection and candidate genes cloning.

Wheat glutamine synthetase TaGSr-4B is a candidate gene for a QTL of thousand grain weight on chromosome 4B

“…One height QTL (LOD: 12.4) attributed to Westonia was overlapped with the TGW QTL (Fig. 6 and Table S8), indicating the overall contribution of plant height to TGW (Wen et al 2022 ).…”

“…In addition, the TGW QTL on 4B has been highlighted by a number of researchers (Li et al 2018 , 2021 ; Xu et al 2019 ; Arif et al 2021 ; Corsi et al 2021 ). In their studies, the TGW QTL was overlapped or very close to the Rht1 locus, or plant height QTL (Li et al 2018 ; Xu et al 2019 ; Guan et al 2020 ; Wen et al 2022 ). However, in our previous study using the population of Westonia and Kauz, the TGW QTL was located beyond the polymorphic Rht1 locus (Zhang et al 2013 ).…”

“…Among those, TGW showed high heritability, indicating the possibility of trait enhancement via genetic manipulation (Zhang et al 2021 ). Several TGW QTL have been identified and potential candidate genes were revealed (Mohler et al 2016 ; Xu et al 2019 ; Guan et al 2020 ; Wen et al 2022 ).…”

“…The TGW QTL on 4B have been particularly highlighted since those are close to or overlapped with one of the green revolution genes— Rht1 gene (Duan et al 2020 ; Guan et al 2020 ; Wen et al 2022 ). However, the TGW QTL in the population of Westonia × Kauz was localized beyond the Rht1 gene (Zhang et al 2013 ).…”

A pleiotropic QTL increased economic water use efficiency in bread wheat (Triticum aestivum L.)

“…Plant height has an important impact on yield components. Several studies have implicated Rht in yield ( Tshikunde et al., 2019 ; Gao et al., 2020 ; Wen et al., 2022 ). For example, plant yield was increased by 16.4 and 8.2% in the Rht12 dwarf lines ( Chen et al., 2018 ), Rht25b showed significant pleiotropic effects on yield components ( Mo et al., 2018 ), Rht4 and Rht8 could reduce plant height to a desirable level and improve yield related traits in the rainfed environment ( Du et al., 2018 ).…”