Seed size is one of the most important agronomic traits determining the yield of crops. Cloning the key genes controlling seed size and pyramiding their elite alleles will facilitate yield improvement. To date, few genes controlling seed size have been identified in soybean, a major crop that provides half of the plant oil and one quarter of the plant protein globally. Here, through a genome-wide association study of over 1800 soybean accessions, we determined that natural allelic variation at GmST05 (Seed Thickness 05) predominantly controlled seed thickness and size in soybean germplasm. Further analyses suggested that the two major haplotypes of GmST05 differed significantly at the transcriptional level. Transgenic experiments demonstrated that GmST05 positively regulated seed size and influenced oil and protein contents, possibly by regulating the transcription of GmSWEET10a. Population genetic diversity analysis suggested that allelic variations of GmST05 were selected during geographical differentiation but have not been fixed. In summary, natural variation in GmST05 determines transcription levels and influences seed size and quality in soybean, making it an important gene resource for soybean molecular breeding.

中文翻译：

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GmST05自然等位基因变异控制大豆种子大小和质量

种子大小是决定作物产量的最重要的农艺性状之一。克隆控制种子大小的关键基因并将其精英等位基因金字塔化将有助于提高产量。迄今为止，在大豆中几乎没有发现控制种子大小的基因，大豆是一种主要作物，提供全球一半的植物油和四分之一的植物蛋白。在这里，通过对 1800 多个大豆种质的全基因组关联研究，我们确定GmST05（种子厚度 05）的自然等位基因变异主要控制大豆种质中的种子厚度和大小。进一步的分析表明，GmST05的两种主要单倍型在转录水平上存在显着差异。转基因实验表明GmST05正向调节种子大小并影响油和蛋白质含量，可能是通过调节GmSWEET10a的转录。种群遗传多样性分析表明，GmST05的等位基因变异是在地理分化过程中选择的，但尚未确定。总之，GmST05的自然变异决定了大豆的转录水平并影响种子大小和质量，使其成为大豆分子育种的重要基因资源。