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 This phenomenon we can observe in the morning glory (Ipomoea tricolor) and Japanese blue morning glory (Ipomoea nil) petals. During the flower development we can observe change of the flower colour form purple to blue. Morning glory has just one delphinidin type anthocyanin and the composition of it does not change during the flower development, but change of the colour is caused by increase of pH in vacuole of coloured cells from 6.6 in buds to 7.7 in fully matured flowers. During the early stage of development acidic pH is maintained by proton pumps, on the latter stage K+/H+ exchanger