Rita Maria de Carvalho-Okano

POLLINATION BIOLOGY OF MABEA FISTULIFERA (EUPHORBIACEAE) IN SOUTHEASTERN BRAZIL

The floral biology of the tree Mabea fistulifera and the behavior of its floral visitors were studied in Vicosa, Minas Gerais State, southeastern Brazil. M. fistulifera is monoecious and self-incompatible. Its inflorescences present a female phase that lasts ten days, followed by a bisexual phase of three days during which animals exploit the nectar and pollen produced by male flowers. Pollination is effected by nocturnal as well as diurnal visitors, including mammals, birds and insects. The bats Artibeus lituratus, Vampyrops lineatus and Sturnira lilium and the opossum Didelphis marsupialis are the nocturnal pollinators. Several passerine birds and bees are the diurnal pollinators. The broad spectrum of unspecialized pollinators suggests that M. fistulifera reproduction may be little affected by disturbances of the animal community. Besides being visited by pollinators, the inflorescences are also visited by nectar thieves such as the flower bat Glossophaga soricina and hummingbirds.

Leguminosae, Papilionoideae no Parque Estadual do Rio Doce, Minas Gerais, Brasil. II: árvores e arbustos escandentes

This work is a floristic survey of arboreous and climbing shrub taxa of Papilionoideae in a semideciduos forest at Parque Estadual do Rio Doce, eastern Minas Gerais State. Field work was carried out from April/1998 to May/1999, when montly visits were conducted to collect botanical material along trails and of the main road. The floristic survey resulted in 22 taxa belonging to eight genera. An identification key, descriptions, illustrations and comments on the analyzed taxa are presented.

Rubiaceae Juss. da Reserva Florestal Mata do Paraíso, Viçosa, MG, Brasil

This work consists of a floristic survey and a taxonomical study of the Rubiaceae at the Mata do Paraiso Forest Reserve in Vicosa, Minas Gerais State, Brazil. Fourteen genera comprising thirty species were found in the Reserve. From this total, nineteen were shrubs and eleven were herbs. The genera with larger species numbers were Psychotria (10), Borreria (four), Coccocypselum (three), and Coussarea and Palicourea (two). Bathysa, Chiococca, Coutarea, Diodia, Faramea, Galium, Mitracarpus, Richardia and Rudgea presented one species. Analytic key, descriptions, illustrations, taxonomical comments and geographic distribution of each species were also presented in this paper.

Acanthaceae da Reserva Florestal Mata do Paraíso, Viçosa, Minas Gerais

A floristic survey of Acanthaceae is presented for the Mata do Paraiso Forest Reserve in the city of Vicosa, state of Minas Gerais, Brazil. The vegetation is mainly composed by forests belonging to the Atlantic Rain Forest Complex. Four genera and six species are recognized: Geissomeria schottiana Nees, Justicia scheidweileri V.A.W. Graham, Mendoncia velloziana Mart., Ruellia brevifolia (Pohl) C. Ezcurra, R. menthoides (Nees) Hiern, and R. subsessilis (Nees) Lindau. R. menthoides is a new record for the state of Minas Gerais. Identification keys for genera and species are provided, as well as descriptions, illustrations, geographic distributions, and comments on the taxonomic problems, uses and habitats of the species.

Fenologia da floração, morfologia floral e sistema de incompatibilidade em espécies distílicas de Rubiaceae em fragmento florestal do Sudeste brasileiro

This work was carried out at the Estacao de Pesquisa, Treinamento e Educacao Ambiental Mata do Paraiso, Vicosa, Minas Gerais State, a forest fragment in the Atlantic Forest. Its main objective was to analyze the flowering phenology, floral morphology, and incompatibility system of the distylous species of Rubiaceae: Palicourea longepedunculata Gardner, P. marcgravii A. St.-Hil., Psychotria conjugens Mull. Arg., P. hastisepala Mull. Arg., P. hygrophiloides Benth., P. nuda (Cham. & Schltdl.) Wawra, P. sessilis Vell. and Rudgea lanceolata Nutt. It also aimed to verify whether the floral morphs were in balanced equilibrium. The flowering in the species of Psychotria conjugens, P. hastisepala, P. hygrophiloides and P. sessilis were sequential, occurring during the rainy season (September through March). Significant differences were observed in the lengths of the stamens and styles between the thrum and pin flowers, except for P. hygrophiloides, in which only thrum flowers could be observed. Furthermore, dimorphism was observed in the length of stigmatic lobules, corollas, corolla lobules and anthers. Flowers opened in the morning lasting about 24 h, except for P. nuda flowers, that lasted 48 h. In most of the species the floral morph ratio was 1:1, except P. marcgravii, P. conjugens and P. hygrophiloides. Heteromorphic self-incompatibility was observed with growth inhibition of the incompatible pollen tubes occurring in the stigma of most of the species analyzed, except for the pin morphs of P. longepedunculata and P. hastisepala, in which reaction occurred in the style.

Cyperaceae do Parque Estadual Paulo César Vinha, Guarapari, Espírito Santo, Brasil

In this paper are presented 38 species of Cyperaceae, ocorring in the restinga vegetation of the Paulo Cesar Vinha State Park, Guarapari, Brazil. Descriptions, illustrations, comments and keys to identification are presented.

Crescimento de mudas de cipó-cravo (Tynanthus fasciculatus Miers), uma liana com potencial medicinal

n Seedling growth of clove-vine (Tynanthus fasciculatus Miers), a liana with medicinal properties, was evaluated under four conditions: forest edge (T1), forest interior (T2), bottom of sloping terrain (T3) and top of sloping terrain (T4). Fifteen seedlings were planted in each treatment. Plant length and number of leaves were recorded monthly for approximately one year. Growth in each treatment was adjusted to simple linear regression models, which were compared by overlapping the obtained confidence intervals. There were significant differences among T1, T2 and T3. Forest edge was the treatment in which seedlings grew better, showing 100% survival and the largest lengths and number of leaves; only in this treatment, the plants developed tendrils in seedlings over 80 cm long.

Malvaceae A. Juss. no Parque Estadual do Rio Doce, Minas Gerais, Brasil

This work consists of a taxonomy treatment of Malvaceae from Rio Doce State Park. In this way, trips were monthly accomplished from October of 1997 to January of 1999, in order to collect botanical material. The morfologic characteres of the staming tube, they were useful for the recognition of the genus. Keys for determination of genus ans species were elaborated, accompanied of descriptions, illustrations, geographical distribution and taxonomic comments of each taxon. Nineteen species were recognized, distributed in nine genus ( Herissantia Medik., Hibiscus L., Malvastrum A.Gray, Pavonia Cav., Peltaea (C.Presl) Standley, Sida L., Sidastrum E.G.Baker, Urena L. and Wissadula Medik.), being Sida the most representative gender which has seven species. Sida santaremensis Monteiro is a new ocorrence citation for the State os Minas Gerais ans Sida acuta var. obidensis Monteiro was proposed as a synonym of Sida planicaulis Cav./

Flowering phenology, nectary structure and breeding system in Corymborkis flava (Spiranthoideae : Tropidieae), a terrestrial orchid from a Neotropical forest

Flowering phenology, breeding system and nectary structure of Corymborkis flava (Sw.) Kuntze were studied in a fragment of the Atlantic Forest in south-eastern Brazil. The flowering period extended from March (end of rainy season) to early June and seed dispersal occurred from June to September (dry season). Flowering peak occurred mainly in April, with up to 34 open flowers per plant being observed. The yellow, odourless and tubular flowers lasted ~7.8 days. The flowers present a perigonal nectary located in the basal lateral parts of the labellum; this is the first report on the nectary location and characterisation in the Tropidieae tribe. At the pre-anthesis stage, cells of both secretory parenchyma and epidermis of the nectary are filled with compound amyloplasts. However, starch grains were not observed in these tissues in senescent flowers, indicating that these starch grains are hydrolysed and used as source of sugars for nectar production. The nectar accumulates between the cuticle and the outer periclinal wall of the epidermal cells before flowing out into the nectar chamber. C. flava is a self-compatible species and spontaneous self-pollination does not occur because of hercogamy. The high pollinia removal (0.80) and insertion (0.82) per flower, as well as the high natural fruit-set indicate an efficient natural pollination system. The present study contributes for the knowledge of the diversity of reproductive strategies and nectary structures in Orchidaceae.

Piperaceae C. Agardh da Estação Experimental Mata do Paraíso, Viçosa, MG

An inventory of the Piperaceae species was made at the Experimental Station of Mata do Paraiso in Vicosa, Minas Gerais State (20o42S and 42o55W), an area covered by the Semideciduous Mesophytic Montana Forest. Thirty visits were made fortnightly to the station, from March/1997 to June/1998, in order to collect botanical material which was deposited in the VIC herbarium (Universidade Federal de Vicosa). Eighteen taxa, represented by the genera Piper L. (14 species), Ottonia Spreng (3 species), and Potliotnorplie Miq. (1 species) were recognized. The most abundant species were Piper caldense CDC, Piper gaudichaudianum Kunth and Piper vicosanum Yunck. Identification keys for the genera and species as well as species descriptions, illustrations and comments are presented.