Network Scan Data

HIGGINS ET AL.: ENCYCUA TAXONOMY 179 coding regions of chloroplast DNA. PI. Mol. Bio. Subtribal and generic relationships of Maxillarieae 17: 1105-1109. (Orchidaceae) with emphasis on Stanhopeinae: The Plant Names Project. 1999. International Plant combined molecular evidence. Am. J. Bot. 87: Names Index. Published on the Internet; http:// 1842-1856. www.ipni.org [accessed 31 July 2003]. Williams, N.H., M.W Chase, T. Fulcher and W.M. Thollesson, M. 2000. Increasing fidelity in parsimony Whitten. 2001. Molecular systematics of the On analysis of dorid nudibranchs by differential cidiinae based on evidence from four DNA se weighting, or a tale of two genes. Mol. Phyl. Evol. quence regions: expanded circumscriptions of Cyrtochilum, Erycina, Otoglossum, and Tricho 16: 161-172. centrum and a new genus (Orchidaceae). Lindley van den Berg, C., W.E. Higgins, R.L. Dressler, W.M. ana 16: 113-139. Whitten, M.A.S. Arenas, A. Culham and M.W. Withner, C.L. 1988. The Cattieyas: The Cattleyas and Chase. 2000. A phylogenetic analysis of Laeliinae their Relatives. Timber Press, Portland, Oregon. (Orchidaceae) based on sequence data from inter ---. 1998. Brassavola, Encyclia, and Other Genera nal transcribed spacers (ITS) of nuclear ribosomal of Mexico and Central America: The Cattleyas DNA. Lindleyana 15: 96-114. and their Relatives. Timber Press, Portland, Whitten, WM., N.H. Williams and M.W Chase. 2000. Oregon. Selbyana 24(2): 180-189.2003. FOLIAR ANATOMY OF FIVE VR/ESEA SECT. X/PH/ON (BROMELIACEAE) SPECIES ROSANI DO CARMO DE OLNEIRA ARRUDA Departamento de Ciencias Naturais, Escola de Ciencias Biol6gicas, Universidade do Rio de Janeiro, Avenida Pasteur, 458, Urca, Rio de Janeiro, 22030-240, RJ, Brasil. E-mail: [email protected] ANDREA FERREIRA DA COSTA* Departamento de Botfurica, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, Sao Crist6vao, 20940-040 Rio de Janeiro, RJ, Brasil. E-mail: [email protected] ABSTRACT. The present work aims to extend the knowledge of the genus Vriesea Lindley, contributing data on the foliar anatomy of five species: Vriesea bituminosa Wawra, V. longiscapa Ule, V. triligulata Mez, V. gigantea Gaudich., and V. Josteriana L.B.Sm. Transverse and longitudinal cuts were made manually in fully expanded leaves. The usual histochemical tests were performed. Features typical to the Bromeli aceae were peltate trichomes, single layered epidermis, stomata located only on the abaxial surface of the leaves, a hypodermis with mechanical and water-storing functions, and collateral vascular bundles. Ob served differences among the species were number of trichomes in both lamina and sheath, number of cells on the trichome shield, and number of layers of the aquiferous hypodermis. Many of the observed char acteristics confirm the xerophytic nature of the leaves. The anatomical organization of the leaves in the studied Bromeliaceae could be related both to environmental pressures as well as to phylogenetic relation ships. RESUMO. 0 presente trabalho tern como objetivo ampliar 0 conhecimento acerca do genero Vriesea Lind ley fornecendo dados sobre a anatomia foliar de cinco especies: Vriesea bituminosa Wawra, V. longiscapa Ule, V. triligulata Mez, V. gigantea Gaudich. e V. Josteriana L.B.Sm. 0 material botanico foi cortado a mao livre. Testes histoquimicos usuais foram realizados. Os resultados mostraram que as especies exibem as caracteristicas tipicas da farm1ia: folhas hipoestomaticas, epiderme simples dotada de tricomas peltados multicelulares, hipoderme com funl(oes meciinica e de reserva de agua, tecido clorofiliano diferenciado em palil(adico e esponjoso do tipo braciforme e feixes vasculares colaterais. Foram notadas diferenl(as entre as especies com relal(ao a quanti dade de tricomas ao longo da folha; mimero de celulas que compoem 0 escudo dos tricomas e mimero de camadas da hipoderme aquffera. As caracteristicas observadas confirmam a natureza xerofftica das folhas. A organizal(ao anatomica das folhas das Bromeliaceae estudadas pode ser uma resposta a press5es ambientais assim como refietir relal(oes filogeneticas. Key words: Bromeliaceae, Vriesea, leaf anatomy, epiphytes INTRODUCTION Although some anatomic studies have been conducted (Tomlinson 1969, Benzing 1970, Comprising nearly 2700 species (Benzing 1976, Braga 1977, Souza & Neves 1996, Sajo 2000) in 56 genera (Grant & Zijlstra 1998), the et al. 1998), the existing data on particular Bromeliaceae family presently represents an ex tremely diversified group of vascular plants, groups are fragmented and little explored, as for which has colonized a variety of neotropical example the genus Vriesea Lindl. Considering habitats (Dahlgren et al. 1985). Specialization the present infra-generic division of Vriesea, the related to water-storage, represented by sheath Section Xiphion comprises ca. 130 species (Lu development as well as xeromorphic leaf struc ther & Sieff 1994, 1997a, 1997b, Luther 2001). ture in many species, is a remarkable feature of These species are characterized predominantly this family, not yet sufficiently investigated. by an inflorescence with dull colors; corolla with Family representatives are found both in xeric cream, yellow, or reddish petals; androecium and mesic environments, from sea level to and gynoecium included within the corolla; and mountaintops, and account for a considerable stigma with the convolute-blade type morphol portion of the epiphytic vegetation in neotropical ogy (Grant 1993, 1995a, 1995b). forests (Benzing 1990). The present work provides data on the foliar anatomy of five species of the Xiphion section * Corresponding author. of Vriesea, which are discussed in the light of 180 ARRUDA & COSTA: VRIESEA FOLIAR ANATOMY 181 possible plant-environment relationships and as view (adaxial and abaxial surfaces) and trans a contribution to the systematics of the family. verse section (FIGURES 1, 2; TABLES 1-3). MATERIAL AND METHODS Face view at median third level The following species were examined: Vrie The epidermis, seen in a face view of the ad sea bituminosa Wawra, V. longiscapa Ule, V. axial surface at the median third level, is com triligulata Mez, V. gigantea Gaudich., and V. posed of trichomes and common epidermal cells Josteriana L.B.Sm. Plant material for the first disposed parallel to the longest axis of the lam three species was collected at Serra de Macae ina (FIGURE 1A). The common epidermal cells, de Cima (Costa 1993), and exsiccates are de rectangular with rather sinuous and thickened posited at the Rio de Janeiro Botanical Garden anticlinal walls, show a siliceous body (FIGURE Herbarium (RB). For the fourth species, material IF). The trichomes are distributed randomly was collected by T. Strehl, in January 1994, at along the epidermal tissue (FIGURE lA, B). His Santo Antonio da Patrulha Municipality, Rio tochemical tests show the presence of phenolic Grande do SuI; and exsiccates are deposited at substances in such cells, the reaction being more Herbarium Alarich Schulz (HAS); and finally V. evident in cells from the central disk. TABLE 1 Josteriana material comes from Espfrito Santo presents the average proportion of trichome dis State and is deposited at Museu Nacional Her tribution over this leaf region. barium (R). On the abaxial surface, the epidermis presents All species are typical tank-bromeliads with organization in costal and intercostal bands of epiphytic habit, except Vriesea Josteriana, ordinary epidermal cells. The presence of sili which is rupicolous. Fully expanded leaves ceous bodies can be observed (FIGURE 1B); the (lamina and sheath) were preserved in ethanol stoIllata are of the tetracytic type with kidney 70° GL (Jensen 1962). Transverse and longitu shaped guard cells, and they are arranged in two dinal sections were then prepared by hand. Sec or four ranks (TABLE 2). Around the stomatal tions were stained with a mixture of safranine complex, the epidermal cells show straight, and Astra blue (Kraus & Arduin 1997). Epider thickened walls, the contents of which present mal analyses were carried out on material dis similar histochemical reactions to those from sociated by immersion in Schultze's mixture subsidiary cells. The stomata may occur either (Sass 1951). Paradermic sections were then isolated or in groups of two to five, among stained with aqueous safranine (Johansen 1940). which the trichomes are located. Trichomes ap Stomata were classified according to Metcalfe (1963). Numbers of stomata and trichomes were pear restricted to intercostal bands (FIGURE 1B) in an average that varies from 13.8 (Vriesea gi recorded as the mean obtained from 20 I-mm2 fields. The number of cells composing the wing gantea and V. longiscapa) to 20.9 (V. trigulata) corresponds to the mean of counting 15 intact (TABLE 1). scales. Sections of non-fixed material were used for the following histochemical tests: Sudan IV Face view at sheath level (Jensen 1962) for cutinized walls and drops of In face view of the epidermis at sheath level, oil, chlorzinc iodine (Strasburger 1924) for cel features generally are similar to those described, lulosic walls; phloroglucinol (Foster 1949) for except for a remarkable absence of stomata on lignified walls; iodine in potassium iodide (Jo either side of the leaf and the presence of tri hansen 1940) for starch; iron sulfate solution chomes that show rather different morphological (Johansen 1940) for phenolic compounds, and features from those of the median third (FIGURE clove oiVphenol (Netolitzki 1935) for siliceous

Load more