Chen Qiang, Liu Bingqiang, Ai Lijuan, Yan Long, Lin Jing, Shi Xiaolei, Zhao Hongtao, Wei Yu, Feng Yan, Liu Chunji, Yang Chunyan, Zhang Mengchen
Hebei Laboratory of Crop Genetics and Breeding, National Soybean Improvement Center Shijiazhuang Sub-Center, Huang-Huai-Hai Key Laboratory of Biology and Genetic Improvement of Soybean, Ministry of Agriculture and Rural Affairs, Institute of Cereal and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang, Hebei, China.
Hebei Key Laboratory of Molecular and Cellular Biology, Key Laboratory of Molecular and Cellular Biology of Ministry of Education, Hebei Collaboration Innovation Center for Cell Signaling, College of Life Science, Hebei Normal University, Shijiazhuang, China.
Front Plant Sci. 2022 Aug 16;13:961619. doi: 10.3389/fpls.2022.961619. eCollection 2022.
Heterophylly, the existence of different leaf shapes and sizes on the same plant, has been observed in many flowering plant species. Yet, the genetic characteristics and genetic basis of heterophylly in soybean remain unknown. Here, two populations of recombinant inbred lines (RILs) with distinctly different leaf shapes were used to identify loci controlling heterophylly in two environments. The ratio of apical leaf shape (LSUP) to basal leaf shape (LSDOWN) at the reproductive growth stage (RLS) was used as a parameter for classifying heterophylly. A total of eight QTL were detected for RLS between the two populations and four of them were stably identified in both environments. Among them, had the largest effect in the JS population, with a maximum LOD value of 46.9 explaining up to 47.2% of phenotypic variance. This locus was located in the same genomic region as the basal leaf shape QTL 20 on chromosome 20. The locus had the largest effect in the JJ population, with a maximum LOD value of 15.2 explaining up to 27.0% of phenotypic variance. This locus was located in the same genomic region as the apical leaf shape QTL 19 on chromosome 19. Four candidate genes for heterophylly were identified based on sequence differences among the three parents of the two mapping populations, RT-qPCR analysis, and gene functional annotation analysis. The QTL and candidate genes detected in this study lay a foundation for further understanding the genetic mechanism of heterophylly and are invaluable in marker-assisted breeding.
异形叶性，即同一植株上存在不同形状和大小的叶片，在许多开花植物物种中都有观察到。然而，大豆异形叶性的遗传特征和遗传基础仍不清楚。在此，利用两个叶形明显不同的重组自交系（RIL）群体，在两种环境下鉴定控制异形叶性的基因座。以生殖生长阶段（RLS）顶叶形状（LSUP）与基叶形状（LSDOWN）的比值作为分类异形叶性的参数。在两个群体之间共检测到8个与RLS相关的QTL，其中4个在两种环境下均被稳定鉴定。其中， 在JS群体中效应最大，最大LOD值为46.9，解释了高达47.2%的表型变异。该基因座位于20号染色体上与基叶形状QTL 20相同的基因组区域。 基因座在JJ群体中效应最大，最大LOD值为15.2，解释了高达27.0%的表型变异。该基因座位于19号染色体上与顶叶形状QTL 19相同的基因组区域。基于两个作图群体的三个亲本之间的序列差异、RT-qPCR分析和基因功能注释分析，鉴定出4个异形叶性候选基因。本研究中检测到的QTL和候选基因为进一步了解异形叶性的遗传机制奠定了基础，在标记辅助育种中具有重要价值。
