AUTHOR=Majeed Uzma , Hou Jian , Hao Chenyang , Zhang Xueyong 

TITLE=TaNAC020 homoeologous genes are associated with higher thousand kernel weight and kernel length in Chinese wheat

JOURNAL=Frontiers in Genetics

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2022.956921

DOI=10.3389/fgene.2022.956921

ISSN=1664-8021

ABSTRACT=<p>NAC proteins constitute one of the largest plant-specific transcription factor (TF) families and play significant roles in plant growth and development. In the present study, three <italic>TaNAC020</italic> homoeologous genes located on chromosomes 7A, 7B, and 7D were isolated from wheat (<italic>Triticum aestivum</italic> L.). <italic>TaNAC020s</italic> were predominantly expressed in developing grains. The developed transgenic rice lines for <italic>TaNAC020-B</italic> showed higher starch density and lower amylose contents than those of the wild type (WT). Sequence polymorphism studies showed seven and eight SNPs in <italic>TaNAC020-A/B</italic>, making three and two haplotypes, respectively. No sequence polymorphism was identified in <italic>TaNAC020-D</italic>. Association analysis revealed that HAP-2 of <italic>TaNAC020-A</italic> and <italic>TaNAC020-B</italic> was the favored haplotype for higher thousand kernel weight and length. Geographic distribution and allelic frequency showed that our favored haplotype experienced strong selection in China, and likewise, diversity increased in <italic>TaNAC020s</italic> during wheat polyploidization. The results obtained in this study demonstrate that <italic>TaNAC020s</italic> positively influence starch synthesis and accumulation and are one of the key regulators of the kernel (seed) size and kernel number and have the potential for utilization in wheat breeding to improve grain yield. Molecular markers developed in this study stand instrumental in marker-assisted selection for genetic improvement and germplasm enhancement in wheat.</p>