Morphoanatomic characterization of the vegetative organs of Miltonia regnellii (Lindl.) Rchb. f. (Oncidiineae, Orchidaceae) - DOI: 10.4025/actascibiolsci.v30i1.1407

Abstract

Miltonia regnellii (Lindl.) Rchb. f. (Oncidiineae, Orchidaceae). The objective of this study was to morphologically and anatomically analyze the vegetative organs of Miltonia regnellii (Lindl.) Rchb. f., in order to characterize the specialized tissues that enable this species to thrive in epiphytic environments. The leaves are covered by a relatively thin cuticle, with the stomata present only in the abaxial surface. A single layer of cells makes up the adaxial hypodermis, and the chlorenchyma is homogeneous. In the collateral vascular bundles, there are fiber sheaths on both poles of conductor tissues, while pseudobulbs and rhizomes present a more evident sheath of fibers only by the phloematic pole. Cells of various dimensions, with thin walls, compose the fundamental parenchyma of the pseudobulb. Roots are composed of three to seven velamen layers and five to eight cortical layers. The exodermis features thin walls, while in the endoderm they are thickened in a “U” or “O” shape when mature