Morphological characterization of kielmeyera coriacea Mart. cork from Brazilian Cerrado

Abstract

Kielmeyera coriacea Mart., known as “pau-santo”, is mentioned in the literature as the main tree species which produces cork of the Brazilian Cerrado. The purpose of this study was to describe the morphological aspect of Kielmeyera coriacea (“pau-santo”) cork cells through its microscopic structure and to compare it with the cellular morphology of Quercus suber (cork oak), which is the main cork producing species worldwide. The bark from three trees of the species Kielmeyera coriacea Mart. was collected randomly at points 1.30 m above the ground, with four repetitions per sample. Samples came from native stands situated in the region of Luminárias - MG, Brazil. The study of morphological characteristics was conducted by counting the number of sides of the cells, and measuring the dimensions of the cells from images obtained by scanning electron microscopy (SEM). Images were analyzed using the LEOUIF software. The distribution in faces and edges of cork cells from Kielmeyera coriacea, was observed to have from 4 to 8 sides, with a predominance of hexagonal cells, similar to Quercus suber. The averages of height and thickness of the cell walls were 40 to 70 μm and 1.5 to 2.0 μm respectively, indicating cells from an early growth season. Both height and thickness were observed to be greater than those present in Quercus suber.