S-EPMC6920156 - Genome-wide identification and analysis of heterotic loci in three maize hybrids. - OmicsDI

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Genome-wide identification and analysis of heterotic loci in three maize hybrids.

ABSTRACT: Heterosis, or hybrid vigour, is a predominant phenomenon in plant genetics, serving as the basis of crop hybrid breeding, but the causative loci and genes underlying heterosis remain unclear in many crops. Here, we present a large-scale genetic analysis using 5360 offsprings from three elite maize hybrids, which identifies 628 loci underlying 19 yield-related traits with relatively high mapping resolutions. Heterotic pattern investigations of the 628 loci show that numerous loci, mostly with complete-incomplete dominance (the major one) or overdominance effects (the secondary one) for heterozygous genotypes and nearly equal proportion of advantageous alleles from both parental lines, are the major causes of strong heterosis in these hybrids. Follow-up studies for 17 heterotic loci in an independent experiment using 2225 F2 individuals suggest most heterotic effects are roughly stable between environments with a small variation. Candidate gene analysis for one major heterotic locus (ub3) in maize implies that there may exist some common genes contributing to crop heterosis. These results provide a community resource for genetics studies in maize and new implications for heterosis in plants.

SUBMITTER: Liu H

PROVIDER: S-EPMC6920156 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Genome-wide identification and analysis of heterotic loci in three maize hybrids.

Liu Hongjun H Wang Qin Q Chen Mengjiao M Ding Yahui Y Yang Xuerong X Liu Jie J Li Xiaohan X Zhou Congcong C Tian Qilin Q Lu Yiqi Y Fan Danlin D Shi Junpeng J Zhang Lin L Kang Congbin C Sun Mingfei M Li Fangyuan F Wu Yujian Y Zhang Yongzhong Y Liu Baoshen B Zhao Xiang Yu XY Feng Qi Q Yang Jinliang J Han Bin B Lai Jinsheng J Zhang Xian Sheng XS Huang Xuehui X

Plant biotechnology journal 20190627 1

Heterosis, or hybrid vigour, is a predominant phenomenon in plant genetics, serving as the basis of crop hybrid breeding, but the causative loci and genes underlying heterosis remain unclear in many crops. Here, we present a large-scale genetic analysis using 5360 offsprings from three elite maize hybrids, which identifies 628 loci underlying 19 yield-related traits with relatively high mapping resolutions. Heterotic pattern investigations of the 628 loci show that numerous loci, mostly with com ...[more]

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