Morfoanatomia dos órgãos vegetativos de Smilax polyantha Griseb. (Smilacaceae)

Abstract

Smilax polyantha Griseb., known as salsaparrilha, is a medicinal plant, occurring in the "cerrado", in the Southeast region in Brazil. The objective of this study was to describe the morphoanatomy of the vegetative organs of Smilax polyantha and to verify whether the characters described in the Brazilian Pharmacopoeia allow to differentiate between salsaparrilha species. Samples of the vegetative organs were prepared following usual techniques using light and scanning electron microscopy. The leaf is hypostomatic and the stomata are paracytic. Mesophyll tends to dorsiventral, as the three parenchyma layers near the adaxial surface are constituted by sinuous cells. Petiole is canaliculated in the adaxial face, and striated in the abaxial face, indicating leaf twist. The stem branch was studied in the aerial and underground portion differing only by the thickening degree of vascular parenchyma cell walls. The rhizophore coat is made by cortical parenchyma; between the cortex and the vascular cylinder there is a secondary thickening meristem; the vascular cylinder has collateral bundles surrounded by parenchyma cells with thick secondary walls. The adventitious radicular system possesses white fresh roots, covered by epidermis, with large cortex, and rigid brown roots, covered by the sclerenchymatous cells of inner cortex, because the epidermis and outer cortex are eliminated along the development. The S. polyantha root analysis had shown that the parameters described in the Brazilian Pharmacopoeia, which are based on the way the roots are tied in bundles, the diameter, and colour of the roots, are insufficient to differentiate the Smilax species.