Skip to main content

ORIGINAL RESEARCH article

Front. Plant Sci.
Sec. Plant Breeding
Volume 16 - 2025 | doi: 10.3389/fpls.2025.1524770

Identification of Quantitative Trait Loci for Yield Traits and Finemapping of qGW4 Using the Chromosome Segment Substitution Line-Z708 and Dissected Single-Segment Substitution Lines

Provisionally accepted
Kai Zhou Kai Zhou Jinjin Yu Jinjin Yu Zhaopeng Yu Zhaopeng Yu Chunyu Chi Chunyu Chi Jialin Ren Jialin Ren Zhuowen Zhao Zhuowen Zhao Han Zhang Han Zhang Yinghua Ling Yinghua Ling Changwei Zhang Changwei Zhang Fangming Zhao Fangming Zhao *
  • Integrative Science Center of Germplasm Creation in Western China Science City, Southwest University, Chongqing, China

The final, formatted version of the article will be published soon.

    Identifying quantitative trait loci (QTL) for grain size using single-segment substitution lines (SSSL) is essential for both targeted breeding and functional analysis of key genes. Here, a wide-grain rice chromosome segment substitution line (CSSL), Z708, carrying four substitution segments from Jinhui35 in the genetic background of Xihui18, was used to identify the QTL associated with grain size. Seven QTL for yield-related traits (qGW4, qRLW4, qGWT4, qGW5, qRLW5, qGWT5, and qGPP5) were identified on the substitution segments of the fourth and fifth chromosomes of Z708. Subsequently, four SSSLs (S1-S4), which harbored 16 QTL for yield traits, were constructed using molecular marker-assisted selection. These lines (S1-S4) exhibited a significant increase in yield per plant compared to that of Xihui18. Among them, qGW4, which controls wide grains, belongs to a single dominant gene action in S1 based on the frequency distribution of grain width and chi-square test analysis. Finally, qGW4 was fine-mapped to the interval of 80-kb (minimum) and 310-kb (maximum) using both traditional fine mapping and overlapping substitution mapping of the newly constructed secondary SSSLs (S5-S8). Within this interval, four previously unreported candidate genes were predicted.

    Keywords: Chromosome segment substitution line, Yield traits, QTL, qGW4, additive effect

    Received: 08 Nov 2024; Accepted: 07 Jan 2025.

    Copyright: © 2025 Zhou, Yu, Yu, Chi, Ren, Zhao, Zhang, Ling, Zhang and Zhao. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

    * Correspondence: Fangming Zhao, Integrative Science Center of Germplasm Creation in Western China Science City, Southwest University, Chongqing, China

    Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.