Genetic Mapping and Validation of Loci for Kernel-Related Traits in Wheat (Triticum aestivum L.).

Xiangru Qu,Xiujin Lan,Yuming Wei,Zhien Pu,Xinlin Xie,Jian Ma,Yutian Gao,Jun Ma,Pengfei Qi,Yaxi Liu,Youliang Zheng,Yang Mu,Huaping Tang,Yang Li,Guoyue Chen,Jirui Wang,Qiantao Jiang,Ahsan Habib,Jiajun Liu,Qiang Xu

doi:10.3389/fpls.2021.667493

Abstract

Kernel size (KS) and kernel weight play a key role in wheat yield. Phenotypic data from six environments and a Wheat55K single-nucleotide polymorphism array–based constructed genetic linkage map from a recombinant inbred line population derived from the cross between the wheat line 20828 and the line SY95-71 were used to identify quantitative trait locus (QTL) for kernel length (KL), kernel width (KW), kernel thickness (KT), thousand-kernel weight (TKW), kernel length–width ratio (LWR), KS, and factor form density (FFD). The results showed that 65 QTLs associated with kernel traits were detected, of which the major QTLs QKL.sicau-2SY-1B, QKW.sicau-2SY-6D, QKT.sicau-2SY-2D, and QTKW.sicau-2SY-2D, QLWR.sicau-2SY-6D, QKS.sicau-2SY-1B/2D/6D, and QFFD.sicau-2SY-2D controlling KL, KW, KT, TKW, LWR, KS, and FFD, and identified in multiple environments, respectively. They were located on chromosomes 1BL, 2DL, and 6DS and formed three QTL clusters. Comparison of genetic and physical interval suggested that only QKL.sicau-2SY-1B located on chromosome 1BL was likely a novel QTL. A Kompetitive Allele Specific Polymerase chain reaction (KASP) marker, KASP-AX-109379070, closely linked to this novel QTL was developed and used to successfully confirm its effect in two different genetic populations and three variety panels consisting of 272 Chinese wheat landraces, 300 Chinese wheat cultivars most from the Yellow and Huai River Valley wheat region, and 165 Sichuan wheat cultivars. The relationships between kernel traits and other agronomic traits were detected and discussed. A few predicted genes involved in regulation of kernel growth and development were identified in the intervals of these identified major QTL. Taken together, these stable and major QTLs provide valuable information for understanding the genetic composition of kernel yield and provide the basis for molecular marker–assisted breeding.

Highlights

IntroductionAccording to the statistics of the Food and Agriculture Organization, the annual yield of wheat must increase 1.6% to ensure the food demand of 9.1 billion people in the world by 2050 (Patil et al, 2013)
Common wheat (Triticum aestivum L. 2n = 6x = 42, AABBDD) is a widely grown cereal crop that provides energy and nutrition for human life
Three variety panels were further used to evaluate the effect of the major quantitative trait locus (QTL), and they were (1) 272 Chinese wheat landraces (CWLs) genotyped by Wheat660K single-nucleotide polymorphism (SNP) array (Zhou et al, 2018); (2) 300 Chinese wheat cultivars (CWCs) collected from different wheat production regions of China, but most from the Yellow and Huai River Valley wheat region genotyped by Wheat55K SNP array (Jin et al, 2020); (3) 165 Sichuan wheat cultivars (SWCs) genotyped by Wheat55K SNP array (Ye et al, 2019)

Summary

Introduction

According to the statistics of the Food and Agriculture Organization, the annual yield of wheat must increase 1.6% to ensure the food demand of 9.1 billion people in the world by 2050 (Patil et al, 2013). With the increase of world population and the decrease of the planting area, increasing food production is of great strategic significance for solving future food supply and security issues. Larger kernels have a positive influence on the vigor of wheat seedlings and yield increasing (Börner et al, 2002) and give a beneficial effect on agronomic values and flour yield (Chastian et al, 1995). TKW was accompanied by a high heritability (Alexander et al, 1984), and KS usually influences TKW to promote yield. Improving KS and TKW is a prior breeding goal to enhance wheat yield and quality

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Results

Discussion

Conclusion