Use morphological and spectral characteristics for bracts in the taxonomy of some species cultivars of the genus Bougainvillea Comm. ex Juss. cultivated in Nineveh and Dohuk governorates/Iraq

Abstract

The presented research included the study of the morphological and spectral characteristics for the bracts in the taxonomy of (6) cultivars of the Bougainvillea Comm. ex Juss. They are: (ʽFormosaʼ and ʽLilac queenʼ for B. glabra Choisy, ʽMary palmerʼ and ʽVera deep purpleʼ for B. spectabilis Willd, ʽThimmaʼ for B. peraviana Hum & Bon and ʽEnid Lancasterʼ for B. x. buttiana). The morphological characteristics included (length and width of bract, shape, apex and base shape of bract, main and secondary colour, arrangement of bract groups and their density). The spectral study included estimating the absorption spectrum of the betalain pigment of the bracts and finding its photon energy using a UV Spectrophotometer. The results showed wide variations among the cultivars of species in the studied morphological characters, especially bract dimensions, shape, main colour, arrangement and density of bract cluster. The results of the spectral study also showed that the cultivars were divided into two main groups according to the type of betalain pigment, the λ max values and photon energy ​​of betalain pigment for bracts. The study of the morphological and spectral characteristics of the bracts cultivars of the Bougainvillea species resulted in clear insights of taxonomic value through the differences in the morphological characteristics and the spectral variation in the λmax values ​​of the betalain pigments of the bracts of the studied cultivars and their photon energy.