A single-cell transcriptomic landscape characterizes the vegetative-to-reproductive transition in wheat

Across flowering plants, the transition from vegetative to reproductive growth represents a key developmental event during which cells and genes will undergo radical changes to reproduction and survival. We found the coordination and differentiation between cell populations, forming a clear boundary prior to entry into reproductive development. Moreover, we discovered two novel cell groups, Anther specific protein and THOUSAND-GRAIN WEIGHT 6 (TGW 6), first appearing respectively at two stages as critical mediators for switching to reproductive development. We delineated developmental trajectories of phloem and epidermal cells and infer gene expression signatures associated with cell fate decisions in the transition process. Taken together, our data provide a special atlas of the early spike with new insights into the plant morphogenesis transition process, cell-fate acquisition, and gene expression dynamics.