Day length has an important influence on flowering and growth habit in many plant species. In crops such as soybean, photoperiod sensitivity determines the geographical range over which a given cultivar can grow and flower. The soybean genome contains ~10 genes homologous to FT, a central regulator of flowering from Arabidopsis thaliana. However, the precise roles of these soybean FTs are not clearly. Here we show that one such gene, GmFT2b, promotes flowering under long-days (LDs). Overexpression of GmFT2b upregulates expression of flowering-related genes which are important in regulating flowering time. We propose a 'weight' model for soybean flowering under short-day (SD) and LD conditions. Furthermore, we examine GmFT2b sequences in 195 soybean cultivars, as well as flowering phenotypes, geographical distributions and maturity groups. We found that Hap3, a major GmFT2b haplotype, is associated with significantly earlier flowering at higher latitudes. We anticipate our assay to provide important resources for the genetic improvement of soybean, including new germplasm for soybean breeding, and also increase our understanding of functional diversity in the soybean FT gene family.

中文翻译：

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大豆对高纬度地区的适应与 GmFT2b 的自然变异有关，GmFT2b 是 FLOWERING LOCUS T 的直系同源物。


日长对许多植物物种的开花和生长习性具有重要影响。在大豆等农作物中，光周期敏感性决定了特定品种可以生长和开花的地理范围。大豆基因组包含大约 10 个与 FT 同源的基因，FT 是拟南芥开花的中心调节因子。然而，这些大豆 FT 的确切作用尚不清楚。在这里，我们展示了这样一种基因，GmFT2b，在长日照（LD）下促进开花。 GmFT2b 的过度表达会上调开花相关基因的表达，这些基因对于调节开花时间很重要。我们提出了短日照 (SD) 和 LD 条件下大豆开花的“权重”模型。此外，我们还检查了 195 个大豆品种的 GmFT2b 序列，以及开花表型、地理分布和成熟度组。我们发现 Hap3（一种主要的 GmFT2b 单倍型）与高纬度地区显着提前的开花有关。我们预计我们的检测将为大豆遗传改良提供重要资源，包括用于大豆育种的新种质，并增加我们对大豆 FT 基因家族功能多样性的了解。