FT5a interferes with the Dt1‐AP1 feedback loop to control flowering time and shoot determinacy in soybean

Flowering time and stem growth habit determine inflorescence architecture in soybean, which turn influences seed yield. Dt1, a homolog of Arabidopsis TERMINAL FLOWER 1 (TFL1), is major controller habit, but its underlying molecular mechanisms remain unclear. Here, we demonstrate that Dt1 affects node number plant height, as well flowering time, soybean under long-day conditions. The bZIP transcription factor FDc1 physically interacts with the FDc1-Dt1 complex directly represses expression APETALA1 (AP1). We propose FT5a inhibits activity via competitive interaction upregulates AP1. Moreover, AP1 by binding to promoter, suggesting form suppressive regulatory feedback loop fate shoot apical meristem. These findings provide novel insights into roles controlling adaptability grain yield this important crop.