Leaf Traits of Calophyllum inophyllum L. (Calophyllaceae) in Different Locations Suggest Suitability for Planting Outside of Natural Habitat

Abstract

Calophyllum inophyllum L. (bitaog), a native tree species in the Philippines that can be found growing in different locations (urban, coastal, and forest areas) with varying climatic conditions, were studied to compare the morphological and anatomical characters in relation to climatic factors. Nine leaf morphological characters (arrangement, apex, base, margin, shape, venation, texture, length, and width) were observed. The thicknesses of the epidermis, vascular tissues, and mesophyll were measured. One-way analysis of variance (ANOVA) was used to show significant differences in morphological and anatomical characters among locations. The linear mixed model was used to determine if leaf characters were affected by precipitation (PPT) and temperature (Temp) in each location. A significant difference in the quantitative morphological characters of C. inophyllum leaves was observed only in leaf length (LL), which was found negatively correlated with leaf width (LW) across locations. Palisade mesophyll (PM) and spongy mesophyll (SM) were found to have significant differences among locations. Leaves in the coastal area, which is the natural habitat of the species, had the thickest mesophyll. It was found out that C. inophyllum grows best in the coastal area and least in the urban area based on the quantitative measurement of leaf morphological characters such as LL and LW. On one hand, trees in the urban area have smaller LL, LW, PM, and SM as affected by the climatic variables. We, therefore, conclude that morphological and anatomical characteristics of C. inophyllum are altered once the species is grown outside of its natural habitat.