QTL mapping for grain yield and three yield components in a population derived from two high-yielding spring wheat cultivars

Kyle Isham,Eduard Akhunov,Jianli Chen,Justin Wheeler,Natalie Klassen,Rui Wang,Weidong Zhao

doi:10.1007/s00122-021-03806-1

Kyle Isham, Eduard Akhunov + Show 5 more

Open Access

https://doi.org/10.1007/s00122-021-03806-1

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Abstract

Key messageFour genomic regions on chromosomes 4A, 6A, 7B, and 7D were discovered, each with multiple tightly linked QTL (QTL clusters) associated with two to three yield components. The 7D QTL cluster was associated with grain yield, fertile spikelet number per spike, thousand kernel weight, and heading date. It was located in the flanking region of FT-D1, a homolog gene of Arabidopsis FLOWERING LOCUS T, a major gene that regulates wheat flowering.Genetic manipulation of yield components is an important approach to increase grain yield in wheat (Triticum aestivum). The present study used a mapping population comprised of 181 doubled haploid lines derived from two high-yielding spring wheat cultivars, UI Platinum and LCS Star. The two cultivars and the derived population were assessed for six traits in eight field trials primarily in Idaho in the USA. The six traits were grain yield, fertile spikelet number per spike, productive tiller number per unit area, thousand kernel weight, heading date, and plant height. Quantitative Trait Locus (QTL) analysis of the six traits was conducted using 14,236 single-nucleotide polymorphism (SNP) markers generated from the wheat 90 K SNP and the exome and promoter capture arrays. Of the 19 QTL detected, 14 were clustered in four chromosomal regions on 4A, 6A, 7B and 7D. Each of the four QTL clusters was associated with multiple yield component traits, and these traits were often negatively correlated with one another. As a result, additional QTL dissection studies are needed to optimize trade-offs among yield component traits for specific production environments. Kompetitive allele-specific PCR markers for the four QTL clusters were developed and assessed in an elite spring wheat panel of 170 lines, and eight of the 14 QTL were validated. The two parents contain complementary alleles for the four QTL clusters, suggesting the possibility of improving grain yield via genetic recombination of yield component loci.

Highlights

Wheat (Triticum aestivum, 2n = 6X = 42, AABBDD genomes) is one of the most important food crops grown today, as it provides 20% of the calories consumed by the world’s population (Breiman and Graur 1995; FAOSTAT 2017)
Transgressive segregation was common at both ends of the distribution for GY, fertile spikelet number per spike (fSNS), and HT, and at one end of the distribution for thousand kernel weight (TKW), PTN, and HD (Fig. 1)
The present study used a doubled haploid (DH) population derived from two high-yielding spring wheat cultivars to dissect the genetic basis of variation for GY, three major yield components, two agronomic traits HD and HT

Summary

Introduction

Through breeding, but the current rate of increase will be insufficient to meet the future needs of a growing population (Ray et al 2013). To meet future demand, breeding for increased grain yield must be accelerated. Because grain yield components, such as fertile spikelet number per spike (fSNS), thousand kernel weight (TKW), and productive tiller number per unit area (PTN), typically show higher heritability than grain yield (Wang et al 2018; Zhang et al 2018), targeting these components for improvement is an important approach to improve grain yield potential in wheat. High grain yield is a result of maintaining a good balance of the three key yield component traits in specific environments. Lines must be tested for grain yield in multiple environments across several years to increase the prospect of developing a new, higher yielding cultivar to release. Because of negative correlations among the three yield component traits, selecting for improvement in

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Conclusion