S-EPMC6611799 - Dissecting a heterotic gene through GradedPool-Seq mapping informs a rice-improvement strategy. - OmicsDI

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Dissecting a heterotic gene through GradedPool-Seq mapping informs a rice-improvement strategy.

ABSTRACT: Hybrid rice breeding for exploiting hybrid vigor, heterosis, has greatly increased grain yield. However, the heterosis-related genes associated with rice grain production remain largely unknown, partly because comprehensive mapping of heterosis-related traits is still labor-intensive and time-consuming. Here, we present a quantitative trait locus (QTL) mapping method, GradedPool-Seq, for rapidly mapping QTLs by whole-genome sequencing of graded-pool samples from F2 progeny via bulked-segregant analysis. We implement this method and map-based cloning to dissect the heterotic QTL GW3p6 from the female line. We then generate the near isogenic line NIL-FH676::GW3p6 by introgressing the GW3p6 allele from the female line Guangzhan63-4S into the male inbred line Fuhui676. The NIL-FH676::GW3p6 exhibits grain yield highly increased compared to Fuhui676. This study demonstrates that it may be possible to achieve a high level of grain production in inbred rice lines without the need to construct hybrids.

SUBMITTER: Wang C

PROVIDER: S-EPMC6611799 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Dissecting a heterotic gene through GradedPool-Seq mapping informs a rice-improvement strategy.

Wang Changsheng C Tang Shican S Zhan Qilin Q Hou Qingqing Q Zhao Yan Y Zhao Qiang Q Feng Qi Q Zhou Congcong C Lyu Danfeng D Cui Lingling L Li Yan Y Miao Jiashun J Zhu Chuanrang C Lu Yiqi Y Wang Yongchun Y Wang Ziqun Z Zhu Jingjie J Shangguan Yingying Y Gong Junyi J Yang Shihua S Wang Wuqi W Zhang Jianfu J Xie Huaan H Huang Xuehui X Han Bin B

Nature communications 20190705 1

Hybrid rice breeding for exploiting hybrid vigor, heterosis, has greatly increased grain yield. However, the heterosis-related genes associated with rice grain production remain largely unknown, partly because comprehensive mapping of heterosis-related traits is still labor-intensive and time-consuming. Here, we present a quantitative trait locus (QTL) mapping method, GradedPool-Seq, for rapidly mapping QTLs by whole-genome sequencing of graded-pool samples from F<sub>2</sub> progeny via bulked- ...[more]

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