RESUMO -(Estratégias anatômicas foliares de treze espécies de Orchidaceae ocorrentes em um campo de altitude no Parque Estadual da Serra do Brigadeiro (PESB) -MG, Brasil). O estudo objetivou caracterizar, anatomicamente, as folhas de Orchidaceae ocorrentes em um campo de altitude (PESB), identificando caracteres anatômicos úteis na interpretação das estratégias adaptativas. As treze espécies estudadas vivem em condições ambientais extremas tendo sido estudados apenas indivíduos terrestres, exceto Pleurothallis teres Lindl. espécie exclusivamente rupícola. Avaliando os caracteres anatômicos adaptativos, dois grupos podem ser distinguidos, os das espécies perenes (Epidendrum secundum Jacq., Epidendrum xanthinum Lindl., Oncidium barbaceniae Lindl., Oncidium blancheti Rchb. F., Pleurothallis prolifera Lindl., Pleurothallis teres Lindl., Zygopetalum brackypetalum Lindl. e Zygopetalum mackaii Hook.) e os das espécies com redução das partes aéreas no período seco (Cleistes gracilis Schdl., Habenaria hydrophila Barb. Rodr., Habenaria janeirensis Kraenzl, Habenaria macronectar Hoehne e Prescottia montana Barb. Rodr.). As espécies perenes apresentam caracteres xeromórficos: folhas coriáceas ou coriáceas suculentas, cutícula espessa e estriada, hipoderme, grupos de fibras esparsas no mesofilo homogêneo, parênquima aqüífero com espessamento em barras ou espiralados nas paredes, idioblastos de ráfides e feixes vasculares colaterais circundados e com calotas de fibras. Nas espécies com redução das partes aéreas ocorrem investimentos diferenciados e os caracteres xeromórficos não são acentuados. As folhas são delgadas, com células epidérmicas adaxiais altas sendo a cutícula delgada geralmente desprovida de estriamentos e a presença de idioblastos de ráfides freqüentes no mesofilo. Não ocorre hipoderme e os feixes vasculares são reduzidos e sem associações com fibras. Palavras-chave:Orchidaceae, anatomia, estratégias adaptativas, folha, campo de altitude ABSTRACT -(Strategies anatomy from thirteen Orchidaceae species occurring in a "high altitude grasslands" in the State Park of Serra do Brigadeiro (PESB) -Minas Gerais State, Brazil). The purpose of this work was to characterize the leaf anatomy of thirteen Orchidaceae species in a "high altitude grasslands", located at State Park of Serra do Brigadeiro, and identify anatomical characteristics helpful to the interpretation of adaptative strategies of these species. The species studied were all terrestrial plants except Pleurothallis teres Lindl. that occurring on granitic rock living in extremely conditions. Observations made in adaptative anatomic features showed that two different groups can be easily distinguished: perennial species (Epidendrum secundum Jacq., Epidendrum xanthinum Lindl., Oncidium barbaceniae Lindl., Oncidium blancheti Rchb. F., Pleurothallis prolifera Lindl., Pleurothallis teres Lindl., Zygopetalum brackypetalum Lindl. and Zygopetalum mackaii Hook.), and species with reduced aerial parts during drought periods (Cleistes gracilis Schdl., Habenaria hydrophila...

-(Anatomy of root of Orchidaceae species of Parque Estadual da Serra do Brigadeiro, Minas Gerais). The present study characterized the root of some orchids occurring in an altitudinal field at the Parque Estadual da Serra do Brigadeiro, pointing out both ecological and taxonomical relevant characters. Only terrestrial individuals were studied, except for P. teres, a rupestrine species. Anatomical comparative analysis of the studied species reveled clear definitions of

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(Tillandsioideae), that occur in Amazonian regions (Mato Grosso-MT), in order to find features of taxonomic value and ecological importance. The studied species are epiphytes and their roots are characterized by a multi-layered velamen, differentiated cortex, uniseriate endodermis and pericycle, polyarch vascular cylinder and medulla with thickened cell walls. Anatomical structures, such as the number of layers and kind of cell wall thickening of the velamen, the kind of thickening of the exodermis and endodermis walls, the presence of idioblasts containing crystals and the number of protoxylem poles help seperate these species within different genera and subfamilies. The presence of mucilage canals in the cortex of A. castelnavii is a diagnostic feature. The roots of Dyckia and Tillandsia share more common features, so there is greater similarity between Pitcairnioideae and Tillandsioideae. Roots with velamen, an exodermis with thickened cell walls constituting a mechanical layer, mucilage canals, air gaps in the inner cortex and idioblasts with crystals are structures adapted to the epiphytic habit.

Abstract:The quantification of genetic diversity and intrapopulation spatial genetic structure (SGS) of tree species are important aspects for in and ex situ conservation practices. In this study we seek to understand the importance of conservation areas by quantifying the genetic diversity and the spatial genetic structure of a natural population of Theobroma speciosum. Within this population, 49 adults and 51 subadults were genotyped for five microsatellite loci. The results showed that adults and subadults have similar levels of genetic diversity and inbreeding (adults: A= 10.4, A e = 10.3, F= 0.68, subadults: A= 10.6, A e = 10.6, F= 0.57). Genetic diversity was spatially structured within the population, and the results suggest that near-neighbor trees up to a distance of 70 m are likely related. SGS is likely the result of short-distance seed dispersal, the short-distance range of pollinators, and infrequent breaches of the self-incompatible mating system. Considering the high demographic density of the species and size of the study area, as well as the high average number of alleles per locus and the presence of rare alleles, we believe that the study population is an excellent resource for in situ genetic conservation of T. speciosum. The study area is also a useful resource for collecting germplasm for ex situ conservation and seed collection, either for breeding programs used in the restoration of degraded areas or forest improvement. Rev. Biol. Trop. 64 (3): 1091-1099. Epub 2016 September 01.Key words: Amazonia, genetic variability, microsatellite markers, cacauhy.The national program of biological diversity, that evaluated and identified priority areas for conservation, sustainable use, and benefitsharing of biodiversity of the Brazilian Amazon, established 27 ecoregions of the Brazilian Legal Amazon (PNJU, 2013). One ecoregion is the Mato Grosso dry forests located in the Northern part of Mato Grosso State. In this area, the Juruena National Park (Parque Nacional do Juruena) was established in 2006 with the aim of protecting endemic Amazonian species. The Conservation Unit (CU) includes headwaters and stretches of important Amazonian rivers, such as Aripuanã, a tributary of the Madeira, Juruena, and Teles Pires Rivers, and tributaries of the Tapajós, and it encompasses an area of significant biogeographical interest. The genus Theobroma occurs naturally in the area.Several species within the Theobroma genus have conventional or potential uses, including Theobroma speciosum Willd. ex Spreng, commonly known as cacauhy. This species is important because it represents a possible source of genetic resistance for other, more economically important species, such as Theobroma cacao (Silva et al., 2011). The fruit rind of T. speciosum is mixed with wood ash to produce a handmade soap that is used in the Amazon and it is an excellent deodorant (Di Stasi & Hiruma-Lima, 2002). In relation to its fatty acids, Gilabert-Escrivá et al. (2002) noted that the composition is very similar to that found in cocoa butter. ...

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No presente trabalho, foi avaliado o efeito da salinidade sobre a germinação de sementes e desenvolvimento pós-seminal de Ochroma pyramidale através de três agentes osmóticos (NaCl, CaCl2 e KCl), em dois experimentos. No primeiro, foi avaliado o estresse salino na germinação em esquema fatorial de 3 x 6, utilizando NaCl, CaCl2 e KCl, e seis potenciais osmóticos (0,0; -0,1; -0,2; -0,4; -0,6 e -0,8 MPa). No segundo experimento, estudou-se o crescimento inicial de plântulas, utilizando os mesmos agentes osmóticos, em quatro potenciais osmóticos (0,0; -0,1; -0,2 e -0,3 MPa), no delineamento inteiramente ao acaso esquema fatorial 3 x 4. O efeito da salinidade interferiu na germinação de sementes O. pyramidale, havendo redução à medida que os potenciais se tornaram mais negativos à produção de massa seca de plântula, percentual de germinação e velocidade do processo germinativo. No potencial osmótico de -0,8 MPa, ocorreu inibição total, evidenciando que o CaCl2 apresentou um efeito inibitório mais acentuado que o NaCl, seguido pelo KCl. No desenvolvimento de plantas, o NaCl provocou maior sensibilidade, comparando-se ao CaCl2 nos maiores potenciais osmóticos.Palavras-chave: Pau-de-balsa; germinabilidade; potencial osmótico; estresse salino. EFFECT OF SALINITY IN THE GERMINATION AND DEVELOPMENT OF Ochroma pyramidale SEEDLINGS ABSTRACT: In the present study, the effect of salinity on seed germination and post-seminal development of Ochroma pyramidale was evaluated through three osmotic agents (NaCl, CaCl2 and KCl) in two experiments. In the first experiment, salt stress in germination was evaluated in a factorial scheme 3 x 6, using NaCl, CaCl2 and KCl; and six osmotic potentials (0.0, -0.1, -0.2, -0.4, -0.6 and -0.8 MPa). In the second experiment, the initial development of plants, using the same osmotic agents, was studied in four osmotic potentials (0.0; -0.1; -0.2 and -0.3 MPa), in a completely randomized design 3 x 4 factorial scheme. The effect of salinity interfered on the germination of O. pyramidale seeds, with reduction as the potentials became more negative for the production of dry seedling mass, percentage of germination and germination speed. In the osmotic potential of -0.8 MPa, total inhibition occurred, evidencing that CaCl2 had a stronger inhibitory effect than NaCl, followed by KCl. In the development of plants, NaCl caused greater sensitivity when compared to CaCl2 in the highest osmotic potentials.Keywords: Pau-de-Balsa wood; germinability; osmotic potential; saline stress.

Orchidaceae is one of the largest botanical families, with approximately 780 genera. Among the genera of this family, Catasetum currently comprises 166 species. The aim of this study was to characterize the root anatomy of eight Catasetum species, verifying adaptations related to epiphytic habit and looking for features that could contribute to the vegetative identification of such species. The species studied were collected at the Portal da Amazônia region, Mato Grosso state, Brazil. The roots were fixed in FAA 50, cut freehand, and stained with astra blue/fuchsin. Illustrations were obtained with a digital camera mounted on a photomicroscope. The roots of examined species shared most of the anatomical characteristics observed in other species of the Catasetum genus, and many of them have adaptations to the epiphytic habit, such as presence of secondary thickening in the velamen cell walls, exodermis, cortex, and medulla. Some specific features were recognized as having taxonomic application, such as composition of the thickening of velamen cell walls, ornamentation of absorbent root-hair walls, presence of tilosomes, composition and thickening of the cortical cell walls, presence of mycorrhizae, endodermal cell wall thickening, the number of protoxylem poles, and composition and thickening of the central area of the vascular cylinder. These traits are important anatomical markers to separate the species within the genus and to generate a dichotomous identification key for Catasetum. Thus, providing a useful tool for taxonomists of this group