Morphoanatomical leaf plasticity of tree species in riparian microenvironments

Abstract

BACKGROUND: Riparian areas show strong environmental heterogenity, which is the result of numerous cycles of flooding and drought. Tree species are able to modify morphoanatomical traits in according with the environmental conditions. OBJECTIVE: The present study characterized and evaluated anatomical traits of leaves of two plant species, Byrsonima intermedia A. Juss. and Byrsonima verbascifolia L. DC, in response to two differents luminosity and water regime.We compared morphoanatomical characteristics in populations of Byrsonima Rich. in order to understand about the coexistence of genus in distincts riparian microhabitats. RESULTS: According to the anatomical studies B. intermedia and B. verbascifolia exhibited morphoanatomical plasticity and for both species the greater thicknesses of palisade parenchyma were found in the population from dry microenvironment, not riparian. In relation to the spongy parenchyma, both studied species did not show significant differences of thickness among populations. The length and width of stomata were significantly different for B. intermedia and partly for B. verbascifolia. The number of stomata varied according to luminosity of microhabitats. In relation to the sclerophylly leaf, B. intermedia showed significant differences on leaf length while B. verbascifolia showed variation in leaf width. The cuticle varied according to riparian microhabitats. The leaves of B. intermedia and B. verbascifolia showed uniseriate epidermis, thicker on adaxial surface. The leaf thickness was significantly different for B. intermedia and not for B. verbascifolia. We found significatives differences in parenchyma and stomata. These anatomical structures are the most sensitive to environmental variations in both species. CONCLUSION: We found significatives differences in parenchyma and stomata. These anatomical structures are the most sensitive to environmental variations in both species