A MORPHOLOGICAL AND MOLECULAR INVESTIGATION OF CORDYLINE HYBRIDS AND CULTIVARS

Many of the coloured-leaved Cordyline cultivars attributed to C. australis have morphological characters more consistent with a hybrid origin. The cultivar ‘Purple Tower’ is stated in reference works to be a hybrid between C. australis and C. banksii but has morphological characters more in keeping with a hybrid of C. indivisa. A molecular investigation was undertaken in order to establish the parentage of the coloured-leaved plants. Sequences of the nuclear ribosomal internal transcribed spacer (ITS) region were gained for 12 taxa but, excepting the tropical C. fruticosa, only one variable site was found. Work continues using low-copy nuclear genes to try to gain the desired information.