Genome-Wide Association Study of Kernel Traits Using a 35K SNP Array in Bread Wheat (Triticum aestivum L.)

Abstract

Kernel size and weight are crucial components of grain yield in wheat. Deciphering their genetic basis is essential for improving yield potential in wheat breeding. In this study, five kernel traits, including kernel length (KL), kernel width (KW), kernel diameter ratio (KDR), kernel perimeter (KP), and thousand-kernel weight (TKW), were evaluated in a panel consisting of 198 wheat accessions under six environments. Wheat accessions were genotyped using the 35K SNP iSelect chip array, resulting in a set of 13,228 polymorphic SNP markers that were used for genome-wide association study (GWAS). A total of 146 significant marker-trait associations (MTAs) were identified for five kernel traits on 21 chromosomes [–log10(P) ≥ 3], which explained 5.91–15.02% of the phenotypic variation. Of these, 12 stable MTAs were identified in multiple environments, and six superior alleles showed positive effects on KL, KP, and KDR. Four potential candidate genes underlying the associated SNP markers were predicted for encoding ML protein, F-box protein, ethylene-responsive transcription factor, and 1,4-α-glucan branching enzyme. These genes were strongly expressed in grain development at different growth stages. The results will provide new insights into the genetic basis of kernel traits in wheat. The associated SNP markers and predicted candidate genes will facilitate marker-assisted selection in wheat breeding.

Genome-wide association study of yield-related traits in common wheat (Triticum aestivum L.) under normal and drought treatment conditions

“…Under the drought treatment conditions, TGW, GW, and SL were reduced by 4, 2, and 6% compared to the normal conditions ( Figure 1 and Table 1 ). However, the broad sense heritability of TGW, GL, GW, and SL was relatively high (76.16 – 95.66%) under both conditions, consistent with previous studies ( Sukumaran et al., 2018 ; Wolde et al., 2019 ; Ji et al., 2021 ; Wang et al., 2021 ; Wang et al., 2022 ). Furthermore, the association panel showed significant phenotypic variation in TGW, GL, GW, and SL under normal and drought conditions.…”

Unlocking the genetic control of spring wheat kernel traits under normal and heavy metals stress conditions

“…Therefore, we can conclude that kernel traits are controlled by a wide genetic base. Previous studies reported the presence of such a wide genetic base for kernel traits using different wheat populations as well as different types of molecular markers (Ramya et al 2010;Okamoto et al 2013;Cui et al 2014;Wang et al 2022). Despite the highly significant correlation that was found among TKW and the remaining kernel traits under the different conditions (Mourad et al 2021b), no or very few markers were found to significantly associated with TKW and other kernel traits (Fig.…”

KASP genotyping of loci associated with the “1000-grain weight” trait in common wheat (Tríticum aestívum L.)

“…К генам, контролирующим массу 1000 зерен, относятся, в частности, TaTGW6-A1, TaGASR7-A1, TaCKX6-D1, TaGs3-D1. Установлено, что определенные SNP, инсерции и делеции в последовательностях этих генов оказывают значительное влияние на активность кодируемых ими ферментов, и, как следствие, величину параметра «масса 1000 зерен» [10]. Проведение KASP-генотипирования пшеницы по генам, ассоциированным с признаком «масса 1000 зерен» с целью выявления генотипов с благоприятными аллелями и включения их в систему скрещиваний, позволит ускорить получение высокоурожайных сортов пшеницы.…”