Ivone Vieira da Silva

Morfologia de sementes e de estádios iniciais de plântulas de espécies de Bromeliaceae da Amazônia

Universidade Do Estado de Mato Grosso - UNEMAT Depto. Biologia, Av. Perimetral Rogerio Silva, 78580-000, Alta Floresta, MT

Use of anatomical root markers for species identification in Catasetum (Orchidaceae) at the Portal da Amazônia region, MT, Brazil

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 Amazonia 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

Morfoanatomia foliar de microorquídeas de Ornithocephalus Hook. e Psygmorchis Dodson & Dressler

Leaf anatomy of O. bicornis Lindl. ex Benth., O. myrticola Lindl., P. pusilla (L.) and P. glossomystax (Rchb. f.) was analyzed to identify valuable taxonomic and ecological traits. Expanded leaves were collected in the Alta Floresta, Mato Grosso State, region. Leaf samples embedded in methacrylate were cut with a table microtome and stained with toluidine blue. Slides were mounted in synthetic resin or in glycerin gelatin. Leaf tissues were dissociated and histochemical tests applied. Plants observed in this study are succulent epiphytes without pseudobulbs. The epidermis is uniseriate and thin, with the exception of O. bicornis which has a relatively thick epidermis, and a thin, smooth cuticle. The species have amphistomatic leaves and the stomata are at the same level as the epidermal cells. Stomata are generally anomocytic and tetracytic in O. myrticola, P. pusilla and P. glossomystax. O. bicornis has tetracytic, anisocytic and actinocytic stomata. Guard cells have thick periclinal walls and small substomatic chambers, except in P. pusilla. With the exception of O. bicornis, species have heterogeneous mesophyll with different types of parenchyma. All vascular bundles are collateral. The species are mesophytic.

Anatomy and micromorphometric analysis of leaf Catasetum x apolloi Benelli & Grill with addition of potassium silicate under different light sources

The aim of this study was to compare vitroplants Catasetum x apolloi grown under natural light and artificial light and different concentrations of potassium silicate, providing data on the anatomical differentiation that aids the acclimatization process of this species. Plants from in vitro seeding were used; 5 protocorms of approximately 0.5 cm were inoculated into vials with a capacity of 500 mL containing 100 mL of alternative culture medium plus potassium silicate (0.0, 0.5; 1.0 mL L-1), pH adjusted to 5.5 ± 0.5 and gelated with 4GL-1 agar before the autoclaving process. Cultures were maintained under natural light (TNE) and artificial light (TAE) for 90 days, and micromorphometric analysis was performed for polar and equatorial diameter, density and stomatal index, blade thickness in the central rib, and secondary veins. Applications in K2SiO4 alternative medium provided the following: elongation of the hypodermis, thicker mesophyll, and more prominent midrib; elipptical guard cells; formation of epistomatal chamber; and lower stomatal density and stomatal with lower equatorial and polar diameters. The conditions that favored the acclimatization were lower light intensities and lower potassium silicate doses.

Leaf anatomy of Qualea parviflora (Vochysiaceae) in three phytophysiognomies of the Mato Grosso State, Brazil

Leaves have a variety of morphological and anatomical characters mainly influenced by climatic, edaphic and biotic factors. The aim of this study was to describe the anatomical leaf traits of Qualea parviflora from three phytophysiognomies. The studied phytophysiognomies were Amazon Savannah on rocky outcrops (ASR), Transition Rupestrian Cerrado (TRC), and Cerradao (CDA). Freehand sections of the leaf blade were made and stained with 0.5% astra blue and with basic fuchsin. From the adaxial and abaxial leaf surface, freehand paradermal sections were made for epidermis analysis. The Jeffrey´s method, with modifications, was used in the epidermis dissociation process. The samples from the TRC phytophysiognomy had relatively smaller ordinary epidermal cells, higher abundance of trichomes, and mesophyll with few intercellular spaces, in comparison to the other phytophysiognomies. The leaves from the ASR phytophysiognomy had higher stomatal index (SI = 21.02), and five to six layers of sclerenchyma surrounding the midrib vascular bundle. The secondary vascular bundles had thicker cell walls and the bundle sheath extended up to the epidermal tissue of both leaf sides. Leaves from the CDA phytophysiognomy had mesomorphic environmental traits, such as a thinner cuticle. It is concluded that trees from ASR and TRC phytophysiognomies have xeromorphic traits following the environmental conditions where they occur.

HISTOLOGICAL ANALYSIS AND PERFORMANCE OF SOUR PASSION FRUIT POPULATIONS UNDER DIFFERENT ROOTSTOCKS RESISTANT TO Fusarium spp

The present study aimed to describe histological traits of the graft welding process and evaluate the effect of rootstocks on the physical and chemical traits and the productivity of sour passion fruit populations. The experiment was arranged in a randomized block design, in a 4x2 + 4 factorial scheme (cultivars / canopy x rootstocks), three replicates and nine plants per plot. Commercial cultivars and populations and Passiflora alata and P. nitida rootstocks, in addition to ungrafted plants were used as canopy. Cleft grafting was the grafting type adopted. Traits analyzed such as productivity and physical and chemical quality of fruits were submitted to analysis of variance and compared by the Tukey test. The canopy morphology was evaluated according to descriptors of the Ministry of Agriculture, Livestock and Supply. Grafting was carried out for each graft/rootstock combination for histological analysis. Sections were obtained by freehand cuts, stained and mounted on semi-permanent slides, examined under optical microscope and photomicrographed. Rootstocks affected the early cultivation and reduced productivity and number of fruits of passion fruit populations. Grafting did not affect the quality of fruits or the canopy morphology. Considering the complete culture cycle, P. alata species is able to be used as rootstock. The anatomical study demonstrates the occurrence of better compatibility in the connection of P. edulis tissues on P. alata, compared to grafting on P. nitida.

DIVERSIDADE GENÉTICA E ESTRUTURA POPULACIONAL DE JATOBÁ: UMA ESPÉCIE COM POTENCIAL ECONÔMICO PARA A AMAZÔNIA

Jatoba ( Hymenaea courbaril L.) is a species that shows ecological importance and occurs in different geographic regions in Brazil. Knowing and evaluating the existence of places with higher genetic variability can help in conservation programs and actions. In this context, the present study aimed to evaluate the genetic diversity and structure in natural populations of Jatoba with occurrence in Mato-Grosso Amazon through ISSR markers. Fifty-four individuals were sampled in three populations, being one in the municipality of Marcelândia (MA=24) and two in the municipality of Alta Floresta (Comunidade Central AF=17 and Pista do Cabeca PC=13 individuals). Total genomic DNA was extracted from the leaf tissue by the CTAB method. The 54 individuals were genotyped with 10 ISSR primers. A total of 110 fragments were amplified, being 78.2% polymorphic. The greatest diversity indices were found in the population from MA (H=0.25; I=0.37 and %P=65.45). The genetic distance was higher among the populations of the two municipalities (0.17 between MA and AF; 0.16 between MA and PC). The analysis of molecular variance (AMOVA) indicated that 31.79 % of the total variance is among populations and 68.21 % within populations. There is genetic diversity in native populations of Jatoba in Mato-Grosso Amazon. We recommend that individuals from both populations are preserved, in order to ensure the maintenance of genetic variability and the effective conservation of species in Mato-Grosso Amazon.

Anatomia e morfometria de raízes e folhas de Urochloa brizantha cv. Marandu em diferentes estádios de acometimento da síndrome da morte das pastagens

Este estudo descreve as alteracoes teciduais em individuos de Urochloa brizantha cv. Marandu de populacoes sob acometimento da sindrome da morte das pastagens (SMP). Foram coletados individuos em tres estadios morfologicos distintos, em uma propriedade rural da Amazonia Meridional, no norte de Mato Grosso. Lâminas histologicas foram montadas a partir de seccoes do terco medio de raizes e das folhas, nelas foram avaliadas as proporcoes e caracteristicas dos tecidos em individuos saudaveis e comparadas com individuos em estadio intermediario e estadio mais avancado da SMP. Nas raizes, foi observada diminuicao do espessamento das paredes celulares da exoderme e endoderme, crescente desorganizacao das celulas corticais, lise celular no floema e medula parenquimatica. Nas folhas, ocorreu diminuicao de tricomas, aumento do tamanho das celulas buliformes, diminuicao de fibras e do mesofilo na nervura central. Aparentemente, a SMP provocou as primeiras alteracoes nas raizes, dificultando o fluxo de substâncias e o funcionamento dos tecidos.

Tropical forages: morphoanatomy of plants grown in areas with the death of pasture syndrome

Roots and leaves of Panicum maximum Tanzânia, Mombaça and Massai; Urochloa brizantha Piatã, Marandu and Xaraés; Urochloa humidicola Llanero; Urochloa ruziziensis Ruzizienses; Urochloa hybrida Mulato II and Cynodon nlemfuensis Estrela-roxa were analyzed, seeking to identify characters for better adaptation to the environment that may interfere with digestibility of tissue from the point of view of the rumen in cattle. Were planted ten cultivars in a completely randomized blocks with three repetitions. Was collected vegetative material, which histological slides were prepared from middle third of the sections of roots and leaves. Were observed differences (p>0.05) in the roots: higher volume of epidermal cells (28.62 µm) and overall diameter (1926.41 µm) of Llanero; thicker vascular cylinder (975.09 µm) and more protoxylem (42.25) in Estrela-roxa and occurrence of aerenchyma in cultivars Piatã, Mulato II, Xaraés, Massai, Llanero and Estrela-roxa; Were found higher proportions of bulliform cells in the leaves (121.07 µm) and thicker leaf mesophyll in U. humidicola Llanero (263.63 µm); higher proportion of sclerenchyma fibers in Xaraés and Marandu; lower results for amount of fibers in P. maximum Massai. We conclude that the cultivars Estrela-roxa, Llanero and Massai have greater adaptability to the environment and better nutritional quality.