Systematics, ecology and ethnobotany of Cinnamomum Schaeffer (Lauraceae) in the Philippines

• Main Author: Picardal, Jay P.
• Format: text
• Language: English
• Published: Animo Repository 2017
• Subjects: Cinnamomum > Philippines; Cinnamon tree > Philippines; Ecology and Evolutionary Biology
• Online Access: https://animorepository.dlsu.edu.ph/etd_doctoral/1188
• Institution: De La Salle University

The genus Cinnamomum is characterized by triplinerved leaves, paniculatecymose inflorescences, and fruits seated on a cupule, mostly with persistent tepals. Cinnamon trees in the Philippines (22 species) are generally aromatic and highly valued in spice and flavor industries, in herbal medicine and furniture industry. Coupled with the potential influence of environmental factors, circumspection of the species which may possess these specific properties is problematic because of extensive phenotypic plasticity in several foliar, floral and fruit characters. To understand how these variations are influenced by ecological factors, this dissertation (1) re-examined the morphological features (stem, leaves, flowers and fruits) and analyzed taxonomic relationships based on variations of morphological characters and cpDNA psbA-trnH intergenic sequences (2) assessed Species Distribution Models and habitat suitability maps to be able to propose an IUCN-based conservation status for each species and (3) reviewed utilization and potential threats to cinnamon diversity and conservation. Herbarium materials were examined, characters assessed and intra- or interspecific variations were shown in a dichotomous key. PCA and AHCA (XLStat 2015) visualized this interspecific relationship and molecular signatures (psbA-trnH) were assigned to each amplified and sequenced cpDNA, where Neighbor-Joining algorithm (MEGA 5.0) was reflected in a phenogram. Georeferencing and Species Distribution Models (Maxent algorithm) were utilized to produce suitability maps to predict favorable habitat of each cinnamon species. Area of occurrence (in km2, QGIS 2.14.1) was used as an objective criterion to propose IUCN Conservation Status of cinnamon species in the Philippines. Ethnobotany and threats were gathered via literature review, actual interviews and photodocumented field observations. Results show that fruit cupula and leaf apex were the most important morphological markers while psbA_trnH cpDNA and morphological characters produced dendrograms based on genetic distance and phenotypic resemblance, respectively. Topologies of classification trees based on morphology and molecular data were relatively congruent and showed that [a] C. mindanaense and C. camphora, [b] C. cebuense and C. mercadoi, [c] C. iners and C. ebaloi and [d] C. griffithii and C. iners were closely related (bootstrap values >70%). SDM suggests that Cebu, Palawan, Bohol, Mindoro, Negros, Masbate, Quezon Province and Laguna could provide the most suitable habitat for most cinnamon species and this will be largely influenced by soil substrate, land cover and isothermality. Proposed conservation status of Philippine cinnamons based on standard IUCN criteria shows that four species are endangered (EN), four species are vulnerable (VU), two species are near threatened (NT) and ten species are data deficient (DD). Habitat loss, climate change and overexploitation are the biggest threats to cinnamon diversity in the Philippines.