The Candidate Photoperiod Gene Promotes Growth and Flowering in .

Flowering time influences the yield and productivity of legume crops. is a reference temperate legume that, like the winter annual , shows accelerated flowering in response to vernalization (extended cold) and long-day (LD) photoperiods (VLD). However, unlike , appears to lack functional homologs of core flowering time regulators () and () which act upstream of the mobile florigen FLOWERING LOCUS T (FT). has three LD-induced genes (, , and ) with promoting flowering in response to VLD. Another photoperiodic regulator in , , acts to induce expression. It also regulates the FT transport pathway and is required for phloem development. Our study identifies a homolog () which complements the late flowering mutant when expressed from the phloem-specific () promoter. Analysis of two insertional mutants indicate that promotes flowering in LD and VLD and growth in all conditions tested. Expression of , , and are reduced in mutant (NF5076), correlating with its delayed flowering. The NF5076 mutant plants are much smaller than wild type indicating that is important for normal plant growth. The second mutant (NF18291) displays seedling lethality, like strong mutants. We searched for mutants in and identifying a knock out mutant (NF20803). However, it did not flower significantly later than wild type. Previously, yeast-two-hybrid assays (Y2H) suggested that FE interacted with CO and NUCLEAR FACTOR-Y (NF-Y)-like proteins to regulate . We found that MtFE interacts with CO and also NF-Y-like proteins in Y2H experiments. Our study indicates that despite the apparent absence of a functional gene, likely influences photoperiodic expression and flowering time in a partially conserved mechanism with .