Wheat Research Institute, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, Henan, China.
Henan Academy of Crop Molecular Breeding, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, China.
BMC Plant Biol. 2020 Oct 12;20(1):469. doi: 10.1186/s12870-020-02674-z.
Ecological environments shape plant architecture and alter the growing season, which provides the basis for wheat genetic improvement. Therefore, understanding the genetic basis of grain yield and yield-related traits in specific ecological environments is important.
A structured panel of 96 elite wheat cultivars grown in the High-yield zone of Henan province in China was genotyped using an Illumina iSelect 90 K SNP assay. Selection pressure derived from ecological environments of mountain front and plain region provided the initial impetus for population divergence. This determined the dominant traits in two subpopulations (spike number and spike percentage were dominance in subpopulation 2:1; thousand-kernel weight, grain filling rate (GFR), maturity date (MD), and fertility period (FP) were dominance in subpopulation 2:2), which was also consistent with their inheritance from the donor parents. Genome wide association studies identified 107 significant SNPs for 12 yield-related traits and 10 regions were pleiotropic to multiple traits. Especially, GY was co-located with MD/FP, GFR and HD at QTL-ple5A, QTL-ple7A.1 and QTL-ple7B.1 region. Further selective sweep analysis revealled that regions under selection were around QTLs for these traits. Especially, grain yield (GY) is positively correlated with MD/FP and they were co-located at the VRN-1A locus. Besides, a selective sweep signal was detected at VRN-1B locus which was only significance to MD/FP.
The results indicated that extensive differential in allele frequency driven by ecological selection has shaped plant architecture and growing season during yield improvement. The QTLs for yield and yield components detected in this study probably be selectively applied in molecular breeding.
生态环境塑造了植物的结构，并改变了生长季节，这为小麦遗传改良提供了基础。因此，了解特定生态环境下的籽粒产量和产量相关性状的遗传基础是很重要的。
利用 Illumina iSelect 90K SNP 检测对中国河南省高产地区种植的 96 个优良小麦品种进行了基因分型。来自山前和平原地区生态环境的选择压力为群体分化提供了最初的动力。这决定了两个亚群的主要特征（在亚群 2:1 中穗数和穗率占优势；在亚群 2:2 中千粒重、灌浆速率（GFR）、成熟日期（MD）和生育期（FP）占优势），这也与供体亲本的遗传一致。全基因组关联研究鉴定出 107 个与 12 个产量相关性状显著相关的 SNP，10 个区域对多个性状具有多效性。特别是，GY 与 MD/FP、GFR 和 HD 共位于 QTL-ple5A、QTL-ple7A.1 和 QTL-ple7B.1 区域。进一步的选择扫描分析显示，选择区域位于这些性状的 QTL 周围。特别是，籽粒产量（GY）与 MD/FP 呈正相关，它们共位于 VRN-1A 基因座上。此外，在 VRN-1B 基因座上检测到一个选择信号，该信号仅对 MD/FP 有意义。
研究结果表明，生态选择驱动的等位基因频率的广泛差异在产量改良过程中塑造了植物的结构和生长季节。本研究中检测到的产量和产量构成的 QTL 可能会在分子育种中得到选择性应用。
