Open Access

ARTICLE

Genome-Wide Identification of Candidate Genes Associated with β-glucan Traits in a Hulled and Hulless Barley (Hordeum vulgare L.) Population

Longhua Zhou^1,2,#, Ting He^1,2,#, Guimei Guo^1,2, Jing Li^1,2, Ruiju Lu^1,2, Yingbo Li^1,2,*, Chenghong Liu^1,2,*

1 Shanghai Academy of Agricultural Sciences, Shanghai, 201106, China
2 Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai, 201106, China
# These authors contributed equally to this work, Chenghong Liu is the first and Yingbo Li is the co-first corresponding author

* Corresponding Authors: Chenghong Liu. Email: ; Yingbo Li. Email:

Phyton-International Journal of Experimental Botany 2020, 89(4), 987-997. https://doi.org/10.32604/phyton.2020.011728

Received 26 May 2020; Accepted 24 June 2020; Issue published 09 November 2020

Abstract

Barley grain is a valuable source of β-glucan, which is an important component of dietary fiber with significant human health benefits. Although the genetic basis of β-glucan biosynthesis has been widely studied, a genome-wide association study (GWAS) is still required for a scan of the candidate genes related to the complex quantitative trait based on the high-quality barley reference genome. In this study, a GWAS was conducted using a population composed of 87 barley landraces (39 hulled and 48 hulless, β-glucan from 2.07% to 6.56%) with 191,098 nucleotide polymorphisms (SNPs) markers to cover the chromosomes with the highest density. The population was divided into four sub-populations (POP1~POP4), and the β-glucan content in POP2 was significantly higher than that in other groups, in which most of the hulless barley landraces are from Qinghai-Tibet Plateau in China. Among seven SNP markers identified by GWAS, two (SNP2 and SNP3) of them showed positive correlation to β-glucan trait and the remaining five (SNP1, SNP4, SNP5, SNP6 and SNP7) showed the negative relationship. Two candidate genes linked to SNP7, HORVU7Hr1G000320 and HORVU7Hr1G000040, belong to the nucleotide triphosphate hydrolase superfamily which is probable to affect the activities of β-glucan synthase. Another candidate gene associated with SNP1, HORVU1Hr1G000010, is possibly involved in sugar response. In conclusion, our results provide new insights into the genetic basis of β-glucan accumulation in barley grains, and the discovery of new SNP markers distributed in each chromosome and the associated candidate genes will be valuable for the breeding of functional barley varieties with high β-glucan.

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