Resumo O tecido tapetal apresenta funções essenciais na formação de células generativas, pois está relacionado a nutrição e desenvolvimento destas nas anteras. Em Bromeliaceae, dentre as poucas espécies descritas, a maioria possui tapete secretor e uma espécie possui tapete invasivo. Neste estudo foram realizadas análises de fases do desenvolvimento de anteras com ênfase ao tapete em Dyckia strehliana com o objetivo de identificar variabilidade em desenvolvimento e estrutura. O material botânico foi coletado as margens do rio Toropi, Rio Grande do Sul, e processados por meio de microtécnica vegetal. Durante a prófase da meiose, as células tapetais de algumas amostras permaneceram parietais enquanto em outras, em número proporcional, inicia-se a invasão no espaço locular, culminando com invasão total durante a fase de micrósporos livres e sem fusão dos protoplastos. A degeneração tapetal está completa antes do início da gametogênese em ambos os tipos. Assim, é possível descrever dois modos de desenvolvimento e estrutura tapetal, um parietal e outro invasivo, embora o tapete permaneça como um tipo secretor geral em ambos os casos. Assim, de acordo com o presente trabalho, os termos invasivo e parietal são indicadores de estados do tapete secretor. generativas Bromeliaceae descritas Toropi Sul vegetal meiose outras proporcional iniciase inicia se locular protoplastos tipos Assim casos trabalho

Abstract Tapetal tissue plays essential roles in the formation of generative cells, as it is related to their nutrition and development in anthers. Among the few species of Bromeliaceae for which tapetal tissue has been describe, most have a secretory tapetum and one has an invasive tapetum. This study analyzed the developmental stages of the anthers of Dyckia strehliana, with emphasis on the tapetum, to identify variability in development and structure. Botanical material was collected on the banks of the Toropi River in the state of Rio Grande do Sul, Brazil, and processed using standard plant micro-techniques. During meiosis prophase, tapetal cells of some samples remained parietal while in the others, a proportional number, the invasion of the locular space begins, culminating in total invasion during the free microspore phase and without fusion of the protoplasts. Tapetal degeneration is complete before gametogenesis begins in both types. Thus, it is possible to describe two modes of development and tapetal structure, one parietal and one invasive, although the tapetum remains as a general secretory type in both cases. Thus, according to present work, the terms invasive and parietal are indicators of states of the secretory tapetum. strehliana structure Sul Brazil microtechniques. microtechniques micro techniques. techniques micro-techniques prophase others number protoplasts types Thus cases work

Resumo Acacia mearnsii e Ilex paraguariensis são espécies arbóreas de grande importância social e econômica no Brasil, que demandam cultivares clonais. Seus brotos possuem estoque de células totipotentes com potencial adequado para enraizamento adventício, essencial para a produção em massa de mudas de alta qualidade. Este estudo teve como objetivo obter novas perspectivas sobre como as barreiras anatômicas, ou seja, tecidos esclerificados na região cortical, podem afetar o enraizamento adventício de miniestacas dessas espécies por meio de estudos histológicos. Para ambas as espécies, a análise histológica revelou características diagnósticas significativas. O apodrecimento de tecidos parece ser equivalente a uma barreira anatômica em A. mearnsii. A abundância de amido foi notável em clones com maior competência de enraizamento de I. paraguariensis, porém não foram observados grãos de amido nos tecidos fundamentais de A. mearnsii, independentemente da competência de enraizamento do clone. As principais diferenças ao enraizamento adventício estavam associadas à velocidade de resposta, que se inicia a partir de meristemoides corticais, seguida pela diferenciação do tecido condutor a partir de um tecido neoformado com estrutura parenquimática, que conecta a periferia com o tecido vascular secundário. Portanto, esse tecido neoformado promove a base estrutural necessária para conexões vasculares radiais. Para ambas as espécies estudadas, a rizogênese apresenta barreiras distintas ao enraizamento, contudo estas não são necessariamente de natureza anatômica. Brasil clonais qualidade anatômicas seja cortical histológicos significativas I clone resposta corticais parenquimática secundário Portanto radiais estudadas

Abstract Acacia mearnsii and Ilex paraguariensis are tree species of great social and economic importance in Brazil, demanding clonal cultivars. Their shoots possess a reservoir of totipotent cells with suitable potential for adventitious rooting, essential for mass production of high-quality seedlings. This study aimed to gain new insights into how anatomical barriers, i.e. sclerified tissues in the cortical region, may affect the adventitious rooting of cuttings from these species through histological examinations. For both species, histological analysis revealed significant diagnostic features. Tissue decay appears to be equivalent to an anatomical barrier in A. mearnsii. Starch abundance was notable in clones with higher rooting competence of I. paraguariensis, but they were not observed in the fundamental tissues of A. mearnsii, regardless of the rooting competence of the clone. The main differences in adventitious rooting were associated with the speed of response, initiated from cortical meristems, followed by differentiation of conductive tissue from newly formed tissue, connecting the periphery with the secondary vascular tissue. Thus, this newly formed tissue with parenchymatic structure provides the necessary structural basis for radial vascular connections. For both studied species, rhizogenesis presents distinct barriers to rooting, nevertheless these are not necessarily of anatomical nature. Brazil cultivars highquality high quality seedlings ie i e i.e region examinations features A I clone response meristems Thus connections nature

Abstract Leaves of mate is one of the main non-timber forest products marketed in South America, which makes establishment of new plantations of great interest. However, vegetative propagation of mate plantlets presents difficulties, which may be associated with the complexity of adventitious root formation. The aims of this study were to anatomically characterize the adventitious roots of mate-clone mini-cuttings and investigate the relationship of phenols and starch with adventitious rooting competence in mini-cuttings treated or not with indole-butyric acid (IBA). The mini-cuttings of four clones were collected at 0, 30, and 60 days of cultivation, fixed in a solution containing 1% glutaraldehyde and 4% formaldehyde, pre-infiltrated and infiltrated in (2-hydroxyethyl) methacrylate, and sectioned in a microtome. Ferric chloride and toluidine blue were used to detect phenolic compounds and lugol to identify starch. Adventitious roots formed in mini-cuttings treated with IBA presented disorganized xylem and phloem and poles irregularly but exhibited sclerenchyma vessel elements and tracheid cells indicating functionality. Differences in the rhizogenic ability of mate clones mini-cuttings were not due to the presence of anatomical barriers or the accumulation of phenolic compounds but be associated with the presence and distribution of starch grains in vegetative propagules.

ABSTRACT This paper presents a morphological analysis of the flower and floral trichomes of three rare species of Dyckia: Dyckia ibicuiensis, D. polyclada and D. racinae. Flowers at anthesis were collected from natural populations and subjected to morphometric and microscopic analysis. Among the most representative features for Dyckia are: morphometrics of individual floral parts; the general configuration of the androecium and gynoecium; the degree of fusion of the stigmatic lobes; the morphology of the ovules, especially in relation to the chalazal appendix; and the presence and constitution of peltate trichomes in the perianth, which exhibited a polymorphism not previously reported for Dyckia. The characters were effective at describing each species, proposing phylogenetic inferences and recognizing infrageneric groupings. We propose two species groups, which are consistent with previous hypotheses about the relationships among the species of the genus. The objective of this study was to provide floral morphological data useful for characterizing these three rare species, delimiting the genus and forming phylogenetic hypotheses.

ABSTRACT This study presents a morphoanatomical analysis of Dyckia ibicuiensis , D. polyclada and D. racinae stamens. Flowers at anthesis were desiccated and their stamens were processed using common light microscopic techniques. Morphologically, the androecium in these species is differentiated by the disposition of the stamens around the gynoecium and by general anther characteristics. Included stamens, with antesepalous filaments different from those of the antepetalous, anthers in a radial disposition, always curved, and sporangia facing the gynoecium characterize D. ibicuiensis and D. racinae . This configuration results from the filament connation, as well as special anatomical characteristics of the anthers, such as the connective with thickenings. In addition, these species are differentiated by the U-shaped thickening in the endothecium. D. polyclada is characterized by its small, free and exserted stamens, with a very short common tube, its anthers, that are not curved or organized around the gynoecium, and its divergent sporangia. The anatomical and morphological characteristics identified here are important for characterization of these species. Considering that the androecium is important in the delimitation of Dyckia , the increased use of these data should be equally important for other species and infrageneric groupings.

Abstract Amphilophium crucigerum (L.) L.G. Lohmann, known as “pente-de-macaco” is a species of Bignoniaceae native to Brazil, and whose seeds are used in folk medicine. This study aimed to describe morphoanatomical features of this species of fruit to aid in its correct identification and pharmacognostic analysis. Samples of ovary, pericarp and seed were fixed with 3% glutaraldehyde, sectioned on a rotary microtome and analyzed by stereomicroscope. The results are shown in three parts: (1) The ovary presents peltate trichomes, long non-glandular trichomes and emergences in the epidermis; it is 2-carpellate and unilocular with two intruding parietal placenta; ovules are numerous on the placenta; it presents a large quantity of crystals. (2) The pericarp is woody, densely echinate and elliptic shape; it presents a 2-valved capsule and is septicidal; it presents emergences, stomata, lenticels, crystals and a large quantity of clustered stones cells. (3) Seeds are alate, exalbuminate and exotestal; there is a large amount of crystals in the exotestal region; it presents an endothelium and remnant endosperm. Histochemical tests showed the presence of lipophilic substances, polysaccharides, phenolic substances, alkaloids and a small quantity of starch. These pharmacobotanical features described for A. crucigerum are essential for the pharmacognostic analysis of the drug plant.

The present work aims to demonstrate the stages of fabrication and use of a simple device to avoid the formation or fixation of precipitates from Sudan Black B solution on tissues. The device consists of four coverslip fragments attached to a histology slide, which serve as points of support for the histological slide under analysis. To work properly, the histology slide with the sections should be placed with the sections facing downwards the device. A small space between the device and the histology slide is thereby created by the height of the coverslip fragments. When Sudan Black B is applied, the solution is maintained within the edges of the device and evaporation is minimized by the small space, thereby reducing the consequent formation of precipitates. Furthermore, by placing the sections facing downward the device, any sporadically formed precipitates are prevented from settling on and fixing to the sectioned tissues or organs. By avoiding the formation of precipitates, plant cells, tissues and organs can be better observed, diagnosed and photomicrographically recorded.

Although this study aims to develop an improved method for the preservation of reserve lipids in plant tissues for different uses in plant anatomy, it mostly aims to develop an improved method for the identification of lipid reserves where synthesis or storage occurs. The proposed procedures entail only the utilization of (2-hydroxyethyl)-methacrylate (HEMA) as a dehydration agent. One of the procedures is based on the gradual exchange of aqueous HEMA solutions with increasing concentrations. In another procedure, dehydration and infiltration are induced by the presence of silica gel around a modified microcentrifuge tube containing the aqueous HEMA solution with the plant tissues, thus allowing efficient lipid preservation. Both procedures resulted in simultaneous dehydration and infiltration of the endosperm and embryo of Ricinus communis, while eliminating the use of ethyl alcohol, thus providing better lipid preservation.

This paper presents a comparative description of the starch distribution in the anthers, microspores and pollen grains of Aechmea recurvata, Dyckia racinae and Tillandsia aeranthos. Flowers at different stages of development were processed according to plant microtechniques for observation by light microscope. Ten stages of embryological development were used as references for the comparative analysis of starch distribution and dynamics. The structural data showed a greater starch accumulation in the parietal layers and connective of D. racinae. It was observed that in the species studied, starch began to accumulate in microspore mother cell stage. The pollen grains in D. racinae and in T. aeranthos present two amylogenesis-amylolysis cycles, while A. recurvata presents only one. One amylogenesis-amylolysis cycle occurs in the parietal layers and/or connective tissue in all three species. The pollen grains in the three species are dispersed without starch and are characterized as the starchless type. Starch dynamics presents a close relation to the development of sporangia, microspores and pollen grains. It is believed that differences in the starch distribution and accumulation are related to the abiotic factors where the species are found.

Durante a investigação do desenvolvimento das anteras e grãos de pólen no clone CP76 de Anacardium occidentale foram observadas anomalias relacionadas ao desenvolvimento do gametófito masculino. Foram observados andrósporos que interromperam seu desenvolvimento momentos antes da primeira mitose, além de grãos que apresentaram anomalias relacionadas à fase inicial da gametogênese masculina. A primeira mitose anômala produziu grãos de pólen binucleados com células idênticas, ou quase, e ainda grãos onde a parede celular, oriunda da primeira mitose, foi incompletamente formada. Fusão nuclear foi observada nos grãos onde a parede celular foi incompletamente formada. A interrupção no desenvolvimento é muito freqüente, ao contrário das anomalias relacionadas à primeira mitose, de ocorrência muito rara

Anomalies of male gametophyte development was observed during anther development investigation in the clone CP76 of Anacardium occidentale. Androspores that stop development before the first pollen mitosis, and grains that show male gametophyte anomalies in early stage of development, was observed. The anomalous first mitosis generate two identical cells, or quite, or grains where cell plate was partially formed. Nuclear fusion occurs in those cells where partial cell walls were formed. The interruption of development before first pollen mitosis occurs in high frequency, on the other hand, the anomalies related with the first pollen mitosis are very rare.

Foram estudados o desenvolvimento floral inicial bem como a ontogênese estaminal em Anacardium occidentale L. As flores apresentam cinco sépalas e cinco pétalas com desenvolvimento helicoidal e unidirecional, respectivamente, androceu com um estame com desenvolvimento heterocrônico e heteromórfico marcante em relação aos nove estames restantes, e um carpelo unilocular terminal. O processo histogênico é idêntico em ambos os tipos de estames. Ao final da ontogênese estaminal, as anteras possuem quatro esporângios, sendo que cada esporângio apresenta epiderme, endotécio, duas camadas médias, tapete e tecido esporogênico. A porção interna do tapete não se origina do conectivo.

The early floral development as well as anther ontogeny in the Anacardium occidentale L. was studied. The flowers present five sepals and five petals with helical and unidirectional development, respectively, and androceum with a stamen with striking heterochronic and heteromorphic development in relation to the remaining nine stamens. At the terminal position an unilocular carpel arises. The histogenic processes is identical in both stamens. At the end of ontogeny both anther types possess four sporangia, with epidermis, endothecium, two middle layers and secretory tapetum, as parietal layers and a sporogenic tissue. The inner portion of the tapetum does not arise from the connective.