Cattleya walkeriana walkeriana" has been twice determined as 2"n" = 40; the diploid chromosome number of the variety "C. walkeriana" var. "princeps" has been determined as 2"n" = 80. Cattleya walkeriana Cattleya walkeriana (Walker's cattleya) is a species of orchid. It differs from most species of "Cattleya" by having inflorescences which arise from the rhizome instead of from the apex of the pseudobulb. In its native habitat (Brazilian Central Plateau) it grows as either an epiphyte or a lithophyte, sometimes in full sun. Pseudobulbs are relatively short, bulbous or fusiform, with one or two ovate leaves at the apex. Inflorescence is one-
Basics of blue flower colouration Basics of blue flower colouration Blue flower colour was always associated with something unusual and desired. Blue roses especially were assumed to be a dream that cannot be realised. Blue colour in flower petals is caused by anthocyanins, which are members of flavonoid class metabolites. We can diversify three main classes of anthocyanin pigments: cyaniding type (two hydroxyl groups in the B-ring) responsible for red coloration, pelargonidin type (one hydroxyl group in the B-ring) responsible for orange colour and delphinidin type (three hydroxyl groups in the B-ring) responsible for violet/blue flower and fruits coloration. The main difference in the structure