Cattleya rex Cattleya rex Cattleya rex is a species of epiphytic orchid of showy white flowers, native to montane forests in Peru and Bolivia. Epiphytic herb with cylindric or spindle-shaped pseudobulbs, up to 35 cm. high, with one leaf at the top. Leaf oblong or elliptic-oblong, obtuse, light green, up to 35 cm. long and up to 6 cm. wide, coriaceous. Inflorescence up to 20.3 cm. high, with 3 to 6 (or 10) flowers. Flowers large and showy, up to 17 cm wide, with sepals and petals being cream-colored or ivory white, except the lip or labellum, which is colored with yellow,
Flowering Locus C produce a number of generations during one summer ("summer-annual"), or (b) flower only after vernalization ("winter-annual" or "late-flowering"). This kind of variation can also be provided by variation in the "FRIGIDA" ("FRI") gene. Flowering Locus C Flowering Locus C ("FLC") is a MADS-box gene that in late-flowering ecotypes of the plant "Arabidopsis thaliana" is responsible for vernalization. In a new seedling "FLC" is expressed, which prevents flowering. Upon exposure to cold, less "FLC" is expressed (to a degree depending on the amount of cold), and flowering becomes possible. "FLC" is extensively regulated through epigenetic modifications and transcriptional control. The expression