Morpho-anatomical study of the cladodes of Homalocladium platycladum (F.J. Muell.) L.H. Bailey (Polygonaceae)

Homalocladium platycladum is a Polygonaceae species, popularly known as fita-de-moca or solitaria that has been used as ornamental and medicinal plant, according to Oriental and Brazilian traditional medicine. The aim of this work was to evaluate the morpho-anatomy of the H. platycladum cladodes. The botanical material was fixed, sectioned and prepared according to usual light and scanning microtechniques. The cladode presented epidermal cells coated with thick and striate cuticle. The uniseriate epidermis showed paracytic stomata and glandular trichomes inserted in small depressions. These trichomes were capitate and presented short stalk and multicellular head. The cortex showed strands of chlorenchyma alternating with sclerenchyma that was an extension of a sclerenchymatic sheath. An internal boundary of the cortex was represented by a starch sheath. The vascular system consisted of collateral bundles and the pith showed parenchymatic cells and idioblasts containing calcium oxalate druses.