Fine Mapping of <i>qTGW7b</i>, a Minor Effect QTL for Grain Weight in Rice (<i>Oryza sativa</i> L.)
Grain weight is a key trait that determines rice quality and yield, and it is primarily controlled by quantitative trait loci (QTL). Recently, attention has been paid to minor QTLs. A minor effect QTL <i>qTGW7</i> that controls grain weight was previously identified in a set of chromosom...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-07-01
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| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/23/15/8296 |
| Summary: | Grain weight is a key trait that determines rice quality and yield, and it is primarily controlled by quantitative trait loci (QTL). Recently, attention has been paid to minor QTLs. A minor effect QTL <i>qTGW7</i> that controls grain weight was previously identified in a set of chromosomal fragment substitution lines (CSSLs) derived from Nipponbare (NPB)/93-11. Compared to NPB, the single segment substitution line (SSSL) N83 carrying the <i>qTGW7</i> introgression exhibited an increase in grain length and width and a 4.5% increase in grain weight. Meanwhile, N83 was backcrossed to NPB to create a separating population, <i>qTGW7b</i>, a QTL distinct from <i>qTGW7</i>, which was detected between markers G31 and G32. Twelve near-isogenic lines (NILs) from the BC<sub>9</sub>F<sub>3</sub> population and progeny of five NILs from the BC<sub>9</sub>F<sub>3:4</sub> population were genotyped and phenotyped, resulting in the fine mapping of the minor effect QTL <i>qTGW7b</i> to the approximately 86.2-kb region between markers G72 and G32. Further sequence comparisons and expression analysis confirmed that five genes, including <i>Os07g39370</i>, <i>Os07g39430</i>, <i>Os07g39440</i>, <i>Os07g39450</i>, and <i>Os07g39480</i>, were considered as the candidate genes underlying <i>qTGW7b</i>. These results provide a crucial foundation for further cloning of <i>qTGW7b</i> and molecular breeding design in rice. |
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| ISSN: | 1661-6596 1422-0067 |