Abstract
Gentian is a perennial plant and known as ornamental flowers. In gentian plant, there was no study about flowering. To identify the machinery of the flowering initiation, we isolated and characterized the gentian FT/TFL1 family genes. First, we obtained three genes possessing high homology to FT/TFL1 and denoted GtFT1, GtFT2 and GtTFL1, respectively. The seasonal expressions of these genes were analyzed. The expressions of GtFT1 and GtFT2 were remarkably increased prior to the flowering initiation, whereas GtTFL1 was highly expressed at vegetative stage and was remarkably decreased just before the flowering initiation. We compared the expression pattern of GtFT/GtTFL1 family with early-flowering (EF) and late-flowering (LF) lines. Both lines showed remarkable increase of GtFT1 and GtFT2 at the flowering initiation. The result suggested that GtFT might play roles in the flowering initiation in gentian. However, the GtTFL1 expression was higher in LF line than that in EF line. Therefore, we compared genomic region of GtTFL1 between EF and LF lines and found that EF line had a 320 bp insertion in promoter region, implying that the insertion may be related to the flowering time.
