The objective of this work was to perform a temporal quantitative analysis, using the scientometric technique, considering the number of citations that the terms Primary Production of Aquatic Macrophytes and Energetic Ecology received in a 50-year period (1956 to 2006). The study related 189 papers published in 26 magazines. It was verified that researchers of several nationalities are working on the proposed themes, with a predominance of those from developed countries (USA and Germany). In Brazil, production on these themes, although small, coincides with the results obtained for other themes analyzed using the same research technique. This fact indicates that greater efforts should be made in the search for more intense scientific production in the country, in the different areas of knowledge, especially in the object of this study.

RESUMO. Com o objetivo de caracterizar os tecidos especializados que tornam Miltonia regnellii (Lindl.) Rchb. f. capaz de ocupação do ambiente epifítico, seus órgãos vegetativos foram analisados morfoanatomicamente. As folhas estão recobertas por cutícula relativamente fina, e os estômatos estão presentes apenas na face abaxial. A hipoderme adaxial está formada por uma camada de células e o parênquima clorofiliano é do tipo homogêneo. Nos feixes vasculares foliares, do tipo colateral, há calotas de fibras em ambos os polos de tecidos condutores, enquanto que, nos pseudobulbos e rizoma, mostram-se com calota mais evidente junto ao polo floemático. Compondo o parênquima fundamental dos pseudobulbos, estão células de dimensões variadas, sempre com paredes finas. Nas raízes, ocorrem 3-5 camadas de velame e 5-8 camadas corticais. A exoderme apresenta paredes pouco espessadas, enquanto que, na endoderme, são espessadas em "U" ou "O" quando maduras.Palavras-chave: epífitas vasculares, orquídea, anatomia vegetal, órgãos vegetativos.ABSTRACT. Morphoanatomic characterization of the vegetative organs of 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.