Morfoanatomia dos 車rg os vegetativos de Miltonia regnellii (Lindl.) Rchb. f. (Oncidiineae, Orchidaceae) = Morphoanatomic characterization of the vegetative organs of Miltonia regnellii (Lindl.) Rchb. f. (Oncidiineae, Orchidaceae)

作者：Greta Aline Dettke; ngela Maria Marques Sanches Marques; Michelli Fernandes; Maria Auxiliadora Milaneze Gutierre

来源：Acta Scientiarum - Biological Sciences, 2008.

• epifitas vasculares
• orquidea
• anatomia vegetal
• org os vegetativos
• vascular epiphytes
• orchid
• plant anatomy
• vegetative organs

Com o objetivo de caracterizar os tecidos especializados que tornam Miltonia regnellii (Lindl.) Rchb. f. capaz de ocupa o do ambiente epif赤tico, seus 車rg os vegetativos foram analisados morfoanatomicamente. As folhas est o recobertas por cut赤cularelativamente fina, e os est matos est o presentes apenas na face abaxial. A hipoderme adaxial est芍 formada por uma camada de c谷lulas e o par那nquima clorofiliano 谷 do tipo homog那neo. Nos feixes vasculares foliares, do tipo colateral, h芍 calotas de fibras em ambosos polos de tecidos condutores, enquanto que, nos pseudobulbos e rizoma, mostram-se com calota mais evidente junto ao polo floem芍tico. Compondo o par那nquima fundamental dos pseudobulbos, est o c谷lulas de dimens es variadas, sempre com paredes finas. Nas ra赤zes, ocorrem 3-5 camadas de velame e 5-8 camadas corticais. A exoderme apresenta paredes pouco espessadas, enquanto que, na endoderme, s o espessadas em ※U§ ou ※O§ quando maduras. 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 thisspecies 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 thepseudobulb. 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.