Open Access

ARTICLE

Discovering Candidate Chromosomal Regions Linked to Kernel Size-Related Traits via QTL Mapping and Bulked Sample Analysis in Maize

by Hameed Gul¹, Mengya Qian¹, Mohammad G. Arabzai^1,2, Tianhui Huang¹, Qiannan Ma¹, Fangyu Xing¹, Wan Cao¹, Tingting Liu¹, Hong Duan¹, Qianlin Xiao^1,*, Zhizhai Liu^1,*

1 College of Agronomy and Biotechnology, Southwest University, Chongqing, 400715, China
2 Department of Agronomy, Faculty of Agriculture, Paktia University, Gardiz, 2201, Afghanistan

* Corresponding Authors: Qianlin Xiao. Email: " />, " />; Zhizhai Liu. Email: " />, " />

(This article belongs to the Special Issue: Integrating Agronomy and Plant Physiology for Improving Crop Production)

Phyton-International Journal of Experimental Botany 2022, 91(7), 1429-1443. https://doi.org/10.32604/phyton.2022.019842

Received 19 October 2021; Accepted 15 December 2021; Issue published 14 March 2022

Abstract

Kernel size-related traits, including kernel length, kernel width, and kernel thickness, are critical components in determining yield and kernel quality in maize (Zea mays L.). Dissecting the phenotypic characteristics of these traits, and discovering the candidate chromosomal regions for these traits, are of potential importance for maize yield and quality improvement. In this study, a total of 139 F2:3 family lines derived from EHel and B73, a distinct line with extremely low ear height (EHel), was used for phenotyping and QTL mapping of three kernel size-related traits, including 10-kernel length (KL), 10-kernel width (KWid), and 10-kernel thickness (KT). The results showed that only one QTL for KWid, i.e., qKWid9 on Chr9, with a phenotypic variation explained (PVE) of 13.4% was detected between SNPs of AX-86298371 and AX-86298372, while no QTLs were detected for KL and KT across all 10 chromosomes. Four bulked groups of family lines, i.e., Groups I to IV, were constructed with F2:3 family lines according to the phenotypic comparisons of KWid between EHel and B73. Among these four groups, Group I possessed a significantly lower KWid than EHel (P = 0.0455), Group II was similar to EHel (P = 0.34), while both Group III and Group IV were statistically higher than EHel (P < 0.05). Besides, except Group IV exhibited a similar KWid to B73 (P = 0.11), KWid of Groups I to III were statistically lower than B73 (P < 0.00). By comparing the bulked genotypes of the four groups to EHel and B73, a stable chromosomal region on Chr9 between SNPs of AX-86298372 to AX-86263154, entirely covered by qKWid9, was identified to link KWid with the positive allele of increasing phenotypic effect to KWid from B73, similar to that of qKWid9. A large amount of enzyme activity and macromolecule binding-related genes were annotated within this chromosomal region, suggesting qKWid9 as a potential QTL for KWid in maize.

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Keywords

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Supplementary Material

Supplementary Material File

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