Field Level Identification of Cinnamomum Species in Sri Lanka Using a Morphological Index

Cinnamomum zeylanicum Blume is a commercially important species cultivated in Sri Lanka and traded as Ceylon cinnamon or true cinnamon. In addition, seven endemic wild species of the genus Cinnamomum have been reported in Sri Lanka. The literature on wild relatives of C. dubium, C. capparucoronde, C. citriodorum, C. litseaefolium, C. ovalifolium, C. rivulorum and C. sinharajaense is limited. Therefore, proper field level identification and differentiation of both wild and cultivated species are critical for the conservation and utilization of such species. Since the cinnamon is a crosspollinated species, intra-species diversity is also a possibility. Our work focused on inter- and intra-species diversity of Cinnamomum leaf morphology to develop a “Leaf Morphological Index” for field-level identification of reported species. Forty accessions, representing a minimum of two from each species, collected from natural and cultivated habitats, were assessed with 12 morphological characters. The highest within-species variation was observed in C. zeylanicum, followed by C. dubium. Of the morphological characters, five-leaf traits, leaf shape, apex, base, venation, and size significantly contributed to the main principle components. Therefore, those traits were used for developing a leaf morphological index. The morphological index could distinguish all the species at the field level.