Protogynous dichogamy, leaf morphology and leaf essential oil composition of selected Cinnamomum species in Sri Lanka

Wild relatives of cultivated cinnamon (Cinnamomum verum J. Presl) are underutilized and endangered in Sri Lanka. There is a lack of knowledge on wild relatives of cinnamon, hampering their utilization in breeding and industry. Morphology, floral behaviour and leaf essential oil composition of selected wild relatives were determined under ex-situ conservation in Dalpitiya, Sri Lanka. Floral cycles were determined in Cinnamomum dubium Nees (Cd) and Cinnamomum litsaeifolium Thwaites (Cl) along with Cinnamomum verum (Cv) variety Sri Gemunu (SG). Cl and SG belonged to type A, while Cd was type B of protogynous dichogamy. Partial overlapping of male and female phases in types A and B may lead to self-pollination. Leaf morphological characters varied among species. Gas Chromatography Mass Spectrometry revealed 34, 34, 12, 48, 8 and 18 chemical compounds from Cinnamomum capparu-coronde Blume (Cc), Cd, Cl (1), Cl (2), SG and variety Sri Wijaya (SW) respectively. The highest abundant chemical compound in leaf oil varied as Eugenol in Cc, SG and SW (33.11%, 82.11% and 90.80% respectively), Methyl eugenol in Cl (1) (59.27%), Eucaliptol in Cd (51.19%) and Linalool in Cl (2) (30.93%). The above variation of wild cinnamon provides insights on future cinnamon breeding and industry.