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The results of the ecological and anatomical study of plants in the coastal shallows of rivers and lakes of the Lower Amur region are presented to identify their resistance and adaptability to the habitat conditions. Seven stenotopic species have been studied. It is revealed that the vegetative organs of plants are characterized by a combination of typical hydromorphic and specific adaptive features. The species are adapted to sandy-clay shallow habitats due to histological transformations of the main tissues. The narrow specialization of species does not affect the typical structure of plant organs and does not cause a simplification of their internal structure. The studied species are to a greater extent characterized by evidences of terrestrial micromorphology (sclerification, suberinization, and cutinization of tissues) rather than of hydrophytic one. It is assumed that a specific complex of flora of shallows is mainly formed by terrestrial species. [ABSTRACT FROM AUTHOR]

Abstract Epiphytes represent approximately 10% of vascular plants, or 25,000 species distributed across 84 families. Water deficit is the greatest challenge faced by epiphytes, resulting in anatomical strategies aimed at maximizing water usage and minimizing water loss. This study aimed to characterize the leaf blade anatomy of 40 species of vascular epiphytes occurring in a cloud forest of the Brazilian Atlantic Forest and assess how leaf anatomy is related to the epiphytic life form. Samples were collected, fixed, dehydrated with ethanol, and embedded in paraffin for sectioning using a microtome or freehand technique. Some samples were dissociated for epidermal observation. A clustering analysis (using UPGMA) was conducted using a presence/absence matrix of 16 anatomical characters. The results showed that species within this functional group exhibit different leaf blade anatomical characteristics, which may or may not be adaptive to epiphytism. However, despite the occurrence of some characteristics such as stomata at the same level as other epidermal cells, thick cuticle, fibers, hypodermis, and homogeneous chlorophyllous parenchyma in 50% or more of the species, there is no set of anatomical characteristics that can be used to define an epiphyte.

Abstract Erythroxylum is common in the Brazilian Cerrado. Species from this genus have ecological, pharmacological and popular medical importance. Based on this information, the aims of this study was to perform a descriptive and quantitative morphoanatomical study of Erythroxylum tortuosum leaves present in two environments: cerrado sensu stricto and campo rupestre. To carry out these studies, 24 fully developed leaves were collected and fixed from individuals across both environments. For the quantitative anatomy study, the following measurements were made: leaf area, length, width and mass; stomatal density; polar and equatorial diameter of the stomata; thickness of the leaf blade, mesophyll, epidermis and cuticles on the adaxial and abaxial surfaces; and thickness of the spongy and palisade parenchyma; specific leaf area, leaf mass area and foliar tissue density. This species shows a bald and uniseriate epidermis when viewed in cross section. Stomata are paracytic and occur only on abaxial surfaces. The mesophyll is dorsiventral type, with a dense vascular system, and the vascular bundle is collateral type. The general pattern of the veins is pinnate camptodrome and brochidodrome, with dense veins and pseudosecondary ribs. Significant differences were found for almost all analysed variables, suggesting that different environmental conditions may influence plant development.

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Copyright of Rodriguésia is the property of Revista Rodriguesia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Soil physical-chemical characteristics are key factors to intraspecific variability in plant functional traits. However, little is known about how wood and leaf traits can interact to ensure similar tree growth and wood quality in sites with different edaphoclimatic conditions. Here, we investigated the effect of soil on the wood features, leaf traits, and plant growth in Eucalyptus urophylla and E. urophylla x grandis trees. Methods: We evaluated the wood features, leaf traits and tree growth in 20 six-year-old trees from the same clone of each species. We applied linear models to verify the variability in these characteristics for both clones in two trial sites. Results: Wood with larger vessels in a lower density, higher potential hydraulic conductivity, taller and wider rays, a higher fraction of vessels and parenchyma cells and a lower fraction of fibers were observed in trees from the trial site with higher availability of water and nutrients. Moreover, the trees had lower specific leaf area and higher leaf dry matter content in this trial site. Conclusion: Our results show that trees studied have similar wood features that ensure safety and relative efficiency in water transport. In addition, we found different leaf traits strategies to optimize carbon uptake, thus maintaining similar productivity and wood quality in sites with different soil conditions. [ABSTRACT FROM AUTHOR]

This study investigated the foliar plasticity in Schwartzia brasiliensis in restinga formations (shrub and shrub-tree restinga) in southern Brazil. In each area, 10 individuals were selected and leaves in sunlight were collected for an analysis of functional leaf traits, including: fresh and dry leaf mass, leaf area, specific leaf area, succulence, stem diameter, plant height and tissue thickness. Environmental variables were measured considering soil mineral nutrition, water availability and photosynthetically active radiation. Phenotypic plasticity index was calculated for studied attribute. We compared means with a Student's t-test and the weight of environmental variables with a PCA. Results showed that the main leaf traits that differentiated the populations were leaf dry mass, specific leaf area, lamina thickness and plant height, while the main predictor environmental variables were gravimetric humidity, solar radiation, soil CEC, phosphorus content and salinity. In the shrub restinga, there is greater investment in mechanical support as a water saving strategy due to greater exposure to solar radiation. In the shrub-tree restinga, there is greater investment in photosynthetic production, since the shade provided by the treetops of other species attenuates the radiation effect. Despite the low plastic potential, the populations present structural adjustments that respond to the environmental heterogeneity. [ABSTRACT FROM AUTHOR]

The biotechnological interest in genus Physalis has increased in the last decades, however, there are still few micropropagation studies of this genus. The objective of this study was to evaluate P. angulata photoautotrophic and photomixotrophic micropropagation with gas exchange under seven light spectra and five concentrations of sucrose. Lighting were yellow, blue, white, red, green, red + blue LEDs and natural light filtered by mesh. Sucrose concentrations were 0, 7.5, 15, 22.5 and 30 g.L-1. Phytotechnical, anatomical features and photopigment contents were evaluated through stem and root segment length, leaf number, leaf area, chlorophyll a and b contents, carotenoids, adaxial epidermis, palisadic and spongy parenchyma and abaxial epidermis. The data were compared by Scott-Knott's mean test and principal components analysis using the R software. Comparing the variables within lighting types, it was observed that only the screen treatment, screen-filtered natural illumination, obtained assessment in all variables. Comparing the levels of sucrose, it was observed that the treatment 15 g.L-1 sucrose obtained the highest number of averages with maximum evaluation. It was concluded that the natural light filtered by screen with 50% of shading allowed the photoautotrophic micropropagation of P. angulata. Better development results were observed in photomixotrophic micropropagation with 15 g.L-1 of sucrose.

This article contains a comparative analysis of the anatomical structure of the rosette and stem leaves of Echinacea purpurea and E. pallida. The plants were grown on the experimental site of the Siberian Botanical Garden, located in the southeastern part of Tomsk (Western Siberia). Temporary preparations of the leaves were prepared by cutting them on a freezing microtome MZ-2. Photographs of leaf microscopy and microscopic measurements were made on a light microscope. Anomocyte type of stomatal complex is characteristic for the studied species. Leaves of the studied species are amphistomatic, rosette leaves of E. purpurea are hypostomatic. The stomatal index of E. purpurea was 1.5 (stem leaves, upper epidermis) and 24.4–25.5 (lower epidermis). In the leaf blade of E. purpurea, the signs are revealed as mesomorphic (the presence of relatively large dorsoventral leaves, moderate development of integumentary, conducting and mechanical tissues) and a xeromorphic-heliomorphic structure. A complex of xeromorphic-heliophytic features of the E. pallida leaf has been identified, which increase its drought resistance; the mean values of the stomatal index of the upper and lower epidermis were 24.8–28.7. There are 10 characteristics that have significant differences in mean values when comparing leaves of E. purpurea and E. pallida: the size of the stomata of the lower epidermis, the thickness of the mesophyll of the leaf, its layers and the leaf laminae free of the vascular bundle, the area of the vascular bundle and their constituents.

Copyright of Bioscience Journal is the property of Bioscience Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Savannas of the Amazon Region of Mato Grosso State have an unique ecological identity due to the complexity of the Cerrado-Amazon transition region, their geographical isolation and the physical-chemical properties of the soil. This study aimed to characterize the leaf anatomy of Xylopia aromatica, and to identify potential adaptive traits to the xeric environment. We collected adult leaves from X. aromatica from a Amazonian savannah located in the Nova Canãa do Norte city, Mato Grosso. The leaves were fixed and stored in 70% ethanol. Cross sections were obtained by free hand with the aid of a razor blade, stained with astra blue and basic fuchsin, and mounted on histological slides. Characters considered adaptive: thick cuticle, epidermal cells with thickened walls, the presence of silica in the epidermis, trichomes, hypostomatic leaves, stomata on the same level as the other epidermal cells, presence of hypodermis, and dorsiventral mesophyll with palisade parenchyma occupying more than 50%. The anatomical characters presented are of great importance for the establishment and development of X. aromatica in xeric environments. They contribute to the protection of the leaves from many biotic and abiotic factors to which they are subjected, thus ensuring the species survival in the savannic environment.

The basic difference between sun and shade leaves arises because of the difference in their exposure to light intensities. To determine the adaptability of Rhizophora mangle L. leaves to different light conditions, we collected leaves from the upper peripheral region (sun leaves) and the internal lower part thereof (shade leaves) of six individuals. The following variables were analyzed: leaf thickness, palisade parenchyma, adaxial and abaxial epidermis, adaxial and abaxial cuticle, density, and stomatal index. The measurements were performed using microscopes equipped with an ocular micrometer. The sun leaves were found to be smaller, with more xeromorphic features such as thicker cuticle and adaxial and abaxial epidermis. The palisade parenchyma and mesophyll of the leaf blade in the sun leaves were found to be thicker than those in the shade leaves, although there was no significant difference in the cuticles of the abaxial face between both the leaf types. The frequency of stomata per square millimeter (average, 70/mm2) was also higher in the sun leaves than in the shade leaves (47 showed/mm2), and there were no differences in the width and length between them to the two types of leaves. Variations between sun and shade leaves indicated an adaptive ability of R. mangle to remain active under varying lighting conditions.

The leaf anatomy has been shown as an important tool to understand the interaction between this organ and its microclimate but this topic is still unclear for citrus plants. The objective of this study was to analyze the leaf structure of Ponkan, Fremont and Thomas tangerine and Murcott tangor. Fully expanded leaves were collected collected, from the 2nd and 3rd nodes of plagiotropic branches facing West, at three crown heights (lower, middle and upper). The leaves were fixed in 70% ethanol and embedded in historesin and sectioned in a semi-automatic microtome. The sections were stained with toluidine blue; images were captured under a light microscope coupled and analyzed to measure leaf tissue thickness. The Fremont tangerine leaves had greater epidermis thickness on the adaxial and abaxial surfaces and secretory cavity diameter as well as a shorter distance between secretory cavities, whereas the Murcott leaves had greater palisade and spongy parenchyma thickness. Thus, Fremont and Murcott are potential varieties for xeric conditions, as they are able to reduce transpiration and make optimal use of high incident radiation. The microclimates created by plant architecture may affect the leaf anatomy of the Ponkan, Fremont and Thomas and Murcott trees, allowing anatomical plasticity. [ABSTRACT FROM AUTHOR]

Highlights • Few studies have examined the root systems of the genus Saccharum. • Endodermal cells with central projections has not been reported for grasses before. • Were found branched root hairs to Saccharum , a rare feature on grasses. • Number of pericycle layers as taxonomic and ecological characteristics. • There is an association between tissue organization and soil moisture. Abstract Most anatomical studies on Saccharum have focused on the above-ground part of the species S. officinarum L. Thus, relatively little is known about the anatomy of South American Saccharum species. The purpose of this study was to describe the root anatomy of the native species S. angustifolium (Nees) Trin., S. asperum (Nees) Steud and S. villosum Steud, in addition to Saccharum aff. villosum 1 and Saccharum aff. villosum 2, and discuss the taxonomic and ecological relevance of our findings. Cross-sections of the roots were evaluated qualitatively with cluster analysis and quantitatively with ANOVA and the Tukey test at the 5% level of significance. The distinctive traits observed (25 qualitative characters and 10 quantitative characters) allowed to identify the species taxonomically and segregate them into three functional groups according to soil type: dry ( S. angustifolium ), moist ( Saccharum aff. villosum 1) and waterlogged (remaining 3 species), shedding new light on aspects of ecological relevance. The anatomical traits observed in the study were found to have significant taxonomic value, especially branched root hairs, endodermal cells with a central projection and multi-layered pericycle, all of which are novel characteristics in the genus. Also ecologically relevant was the finding that different species growing under similar soil conditions displayed similar adaptive strategies. Thus, in this study we report the occurrence of two cryptic species of the Saccharum villosum complex ( Saccharum sp. nov. 1 and Saccharum sp. nov. 2). [ABSTRACT FROM AUTHOR]

Highlights • The species showed changes in leaf blade and wood anatomy under different stages of forest succession. • Anatomical attributes are the key for developed at each site. • The species showed structural adjustment through changes in forest microclimate. • The specie allowed adjustment in photosynthetic efficiency and safety water transport. Abstract We analyzed the effects of two different successional stages on leaf and wood anatomy of Psychotria schlechtendaliana in a tropical moist forest. Leaf and wood samples were collected from plants growing in two sites representing two successional stages: advanced and intermediate stages of forest succession (ASFS and ISFS, respectively). The leaves have typical mesomorphic anatomy. Wood exhibits growth rings slightly different. The vessels elements are solitary, arranged radial or in clusters, with diffuse porosity, simple perforation plates, septate fibers, radial parenchyma multiseriate, and heterogeneous and perforated ray cells, intervessel pits bordered, small, alternate, vestured and/or scalariform. Quantitative analyses showed significantly differences in leaf and wood anatomy. Top and base leaves on both sites differed in the thickness of cuticle, palisade parenchyma, and palisade:spongy parenchyma ratio. Plants at ISFS had leaf lamina with thinner adaxial cuticle, smaller cells on the adaxial epidermis, smaller width of palisade parenchyma, smaller palisade:spongy parenchyma ratio, and lower stomatal density than at ASFS. The wood of plants in ISFS had presented smaller diameters of the lumen of vessels and fibers, higher frequencies of vessels and rays, and fiber and rays with longer lengths than at ASFS. The differences between leaf and wood anatomy at the two sites confirm a structural adjustment in relation to forest succession for this species. The anatomical differences reflect the sunlight distribution and water availability, allowing the adjustment in photosynthetic efficiency, and safety water transport. [ABSTRACT FROM AUTHOR]

Chaetostoma glaziovii Cogn. is an endemic species of the Brazilian flora and grows exclusively in fields at elevations above 2000 meters. It belongs to Melastomataceae family, Microlicieae tribe, which presents little variation on vegetative organs, making it difficult to identify sterile individuals. Anatomical studies, using optical and scanning electron microscopes are carried on comparing the data with the anatomical characteristics of xeromorphic plants, cited in the literature, to check its similarities. This study aims, also, highlight data that may contribute to characterization of the species due to the great similarities among sterile individuals within the tribe. Leaf and stem anatomical data of C. glaziovii are interpreted considering climatic factors, aiming to understand the species' successful establishment in an environment characterized by intense light exposure, strong winds and extreme temperatures. The material was collected in the Itatiaia National Park at an altitude of 2350 meters, latitude S 22° 23' 26" and longitude W 44° 40' 17". Histochemical tests were performed on unfixed samples to identify starch grains, lipids, phenolic compounds, glycides and crystals. It is noteworthy the great amount of fibers on the abaxial and marginal regions of leaf blade, forming an armor against environmental aggressions. In addition, this characteristic is valued from the taxonomic perspective because no other species of the tribe exhibits such extensive fiber development. The anatomical data revealed that some characteristics of C. glaziovii are like those found on xeromorphic plants and are important for its identification beyond to contribute for understanding the intricate plant-environment relationships. [ABSTRACT FROM AUTHOR]

The pollution of water bodies with heavy metals is generating increasing concern worldwide, and among those heavy metals, cadmium is one of the most toxic elements released into the environment. The present study aimed to evaluate the anatomical and physiological modifications adopted by the water hyacinth (Eichhornia crassipes) under cadmium contamination. The plants were grown in Hoagland solution in a greenhouse at five cadmium levels: 0.00, 3.5, 7.0, 14.0, and 28.0 μM. The net photosynthesis, stomatal conductance, transpiration rate, Ci/Ca ratio, antioxidant system enzymes activity, and anatomical traits in plant roots and leaves were evaluated. The plants exhibited increased photosynthesis, stomatal conductance, transpiration, and Ci/Ca ratios in all treatments containing cadmium. Antioxidant system enzymes displayed increased activity in the roots and leaves of plants treated with cadmium. Plants exhibited higher stomatal density and spongy parenchyma thickness under Cd contamination. The anatomical traits of the roots exhibited no evidence of toxicity or improved vascular system traits. Thus, Eichhornia crassipes demonstrated an ability to tolerate Cd by adopting changes in the anatomy, gas exchange and antioxidant system.

Visando contribuir para o conhecimento das respostas morfoanatômicas de espécies arbóreas à hipoxia, efeitos do alagamento em órgãos vegetativos de Aegiphila sellowiana foram estudados. Indivíduos jovens foram mantidos em substrato drenado e alagado por 50 e 80 dias. Houve mortalidade de 40% das plantas alagadas. As sobreviventes produziram fissuras peridérmicas na base do hipocótilo, raízes diageotrópicas e lenticelas hipertrofiadas em hipocótilos e raízes. Em plantas alagadas: (1) as raízes secundárias apresentaram maior diâmetro, córtex mais espesso, células corticais maiores, espaços intercelulares maiores, cilindro vascular e elementos de vaso menores; (2) as raízes primárias em estrutura secundária e hipocótilos apresentaram súber e feloderme mais espessos; (3) as folhas apresentaram nervura mediana e mesofilo mais espesso, tricomas mais abundantes e estômatos menores. Constatou-se que A. sellowiana é intolerante ao alagamento do solo, fato evidenciado pela morte de parte das plantas. Entretanto, as sobreviventes apresentaram modificações morfoanatômicas que conferem tolerância. Sugere-se que a capacidade diferencial de tolerância apresentada entre os indivíduos pode ser resultado da presença de diferentes genótipos dentro do conjunto de plantas utilizado neste estudo.In order to uncover the morpho-anatomical responses of tree species to hypoxia, we studied the effects of flooding on vegetative organs of Aegiphila sellowiana. Young individuals were kept in drained and flooded soil for 50 and 80 days. Under flooding, there was a mortality rate of 40%. The surviving plants produced peridermic fissures, superficial roots and hypertrophied lenticels. Secondary roots of flooded plants presented greater diameter, thicker cortex, greater diameter of the cortical cells, larger intercellular spaces, and thinner vessel elements and vascular tissues. In the main roots under secondary growth and hypocotyls, cork and phelloderm became thicker under flooding. Leaves of flooded plants presented thicker midrib, larger mesophyll, higher number of trichomes and smaller stomata. Considering that part of the plants subject to flooding have died, it is possible to suggest that A. sellowiana is intolerant of soil inundation. However, the surviving plants showed morpho-anatomical modifications that could have conferred some tolerance to them. Thus, the differential tolerance observed among individuals of A. sellowiana indicates a variability of genotypes in the samples used in this study.

Este trabalho teve como objetivo a avaliação das características anatômicas e fisiológicas de aguapé (Eichhornia crassipes) em resposta ao estresse por arsênio. As plantas de aguapé foram cultivadas em solução nutritiva hidropônica de Hoagland em casa de vegetação sob cinco concentrações de arsênio: 0,0; 0,25; 0,5; 1,0; e 2,0 mg L-1 por período de 20 dias. As plantas demonstraram aumento na taxa fotossintética, na condutância estomática, na transpiração e na relação Ci/Ca, bem como na atividade de todas as enzimas do sistema antioxidante, com maior atividade nas folhas em relação às raízes nos tratamentos contendo arsênio. As características anatômicas das folhas das plantas sob as maiores concentrações de arsênio mostraram aumento na densidade estomática, no índice estomático e na espessura do parênquima esponjoso. A anatomia radicular não evidenciou alterações decorrentes da intoxicação por arsênio e modificações nas características do xilema e floema, porém não houve prejuízos à sua estrutura e função. Dessa forma, o estresse por intoxicação pelo arsênio, nas concentrações testadas, não é evidente nas plantas de E. crassipes, e os mecanismos de tolerância são relacionados com modificações na anatomia e fisiologia das plantas.This work aimed to evaluate the anatomical and physiological characteristics of Eichhornia crassipes in response to arsenic stress. Plants of E. crassipes were grown in Hoagland hydroponic nutritive solution under greenhouse conditions at five arsenic levels: 0.0, 0.25, 0.50, 1.0 and 2.0 mg L-1 during 20 days. The plants showed an increase in photosynthetic rate, stomatal conductance, transpiration and Ci/Ca rate, as well as in the activity of all the enzymes in the antioxidant system, with higher activity in the leaves than in the roots, in all the treatments with arsenic. The anatomical characteristics observed on the leaves of the plants under higher arsenic levels showed an increase in stomatal density, stomatal index and spongy parenchyma thickness. Root anatomy showed no toxic evidences at any arsenic level; changes in the xylem and phloem characteristics were exhibited by the roots in the arsenic treatments, but no damage was caused to its structure and function. Thus, stress caused by arsenic intoxication at the levels tested, is not evident on E. crassipes plants, and the mechanisms of tolerance of E. crassipes are associated to anatomical and physiological changes.

Sebastiania commersoniana é uma espécie arbórea bastante comum em ambientes aluviais, em diversas condições pedológicas, graças a sua plasticidade e capacidade de tolerar períodos de inundação. Foram amostrados 21 indivíduos adultos dessa espécie, na planície do rio Iguaçu, visando à caracterização anatômica da madeira e sua interpretação em termos funcionais. S. commersoniana possui porosidade difusa, vasos solitários e múltiplos de dois a seis, com arranjo radial e placas de perfuração simples. Os vasos são pouco freqüentes (12-16-20/mm²), com diâmetro de 54-88-117 µm e elementos de vaso com comprimento 164-602-1025 µm. As fibras libriformes têm 656-1222-2050 µm de comprimento, 10-26-42 µm de largura, e paredes delgadas a espessas (1,0-2,8-5,1 µm). Fibras gelatinosas são freqüentes. Ocorre parênquima apotraqueal difuso em agregados, e paratraqueal escasso. Os raios, unisseriados, têm 164-805-2787 µm de altura e 12-22-35 µm de largura. Células perfuradas de raio são freqüentes, bem como máculas contendo grãos de amido. Estes também ocorrem no parênquima radial e no axial. A espécie desenvolve lenho de tensão em árvores inclinadas. A maioria dos caracteres observados coincide com descrições disponíveis para o gênero e a família a que a espécie pertence. Algumas características qualitativas são discutidas quanto às suas possíveis funções e implicações para a auto-ecologia da espécie.Sebastiania commersoniana is a very common tree species in alluvial environments with diverse soil conditions due to its plasticity and ability to tolerate periods of flooding. In this study we sampled 21 adult individuals of this species on the Iguaçu River plain, for wood anatomy characterization and interpretation using a functional approach. S. commersoniana has diffuse porous, solitary vessels and multiples of two to six, radially arranged with simple perforation plates; low vessel frequency (12-16-20/mm²), with diameter of 54-88-117 µm, and vessel elements 164-602-1025 µm in length. The fibers are 656-1222-2050 µm in length, 10-26-42 µm wide, the walls are 1.0-2.8-5.1 µm thick. Fibers with a gelatinous layer are common. Apotracheal parenchyma diffusein-aggregates is found, while paratracheal parenchyma is scanty. Rays are uniseriate, 164-805-2787 µm tall and 12-22-35 µm wide. Perforated ray cells are frequent, as well as scar tissue containing starch grains. Starch also occurs in the radial and axial parenchyma. This species develops tension-wood in inclined trees. Most of the features observed coincide with available descriptions of the genus and family to which the species belongs. Some qualitative features are discussed on the base of possible roles and implications for species autoecology.

Foi estudada a anatomia de raízes, rizomas, folhas e escapos de Cyperus odoratus L., Oxycaryum cubense (Poep. & Kunth) Lye e Pycreus macrostachyos (Lam.) Raynal (Cyperaceae-Poales) de lagoas do semi-árido da Bahia visando caracterizar anatomicamente as espécies e levantar estruturas adaptativas à forma de vida anfíbia. As espécies apresentam raízes com epiderme unisseriada, córtex com exoderme e lacunas de ar. Os rizomas apresentam feixes vasculares anfivasais ou colaterais no cilindro vascular. As folhas apresentam epiderme unisseriada, com células de parede periclinal externa mais espessada que a interna, estômatos somente na face abaxial, parênquima clorofiliano alternado com lacunas de ar e feixes vasculares colaterais. Os escapos apresentam epiderme unisseriada, feixes de fibras distribuídos perifericamente alternados com parênquima clorofiliano, lacunas de ar e feixes vasculares colaterais. Oxycaryum cubense difere de Cyperus odoratus e Pycreus macrostachyos por apresentar raízes com pêlos longos, rizomas e estolões com feixes vasculares colaterais, folhas com bordo agudo, e ausência de estrutura Kranz nas folhas e escapos. Características anatômicas como: lacunas de ar observadas principalmente nas raízes, células buliformes na face adaxial da epiderme foliar, hipoderme, reduzido número de elementos xilemáticos e pouca lignificação nas paredes celulares dos tecidos nos diferentes órgãos estudados são consideradas importantes na adaptação dessas plantas anfíbias às lagoas temporárias do semi-árido da Bahia.We examined the anatomy of roots, rhizomes, leaves, and scapes of Cyperus odoratus L., Oxycaryum cubense (Poep. & Kunth) Lye, and Pycreus macrostachyos (Lam.) Raynal (Cyperaceae-Poales) from temporary lakes in the semi-arid region of Bahia in order to characterize the anatomy and examine structural adaptations to amphibious lifestyle. All species had roots with uniseriate epidermal cells, cortex with exoderm and air canals. The rhizomes had amphivasal or collateral vascular bundles in the vascular cylinder. The leaves had uniseriate epidermal cells with external periclinal cell walls thicker than the inner walls, stomata on the abaxial leaf surface, chlorenchyma alternating with air canals, and collateral vascular bundles. The scapes had uniseriate epidermal cells, fibrous groups distributed peripherally, alternating with chlorenchyma, air canals, and collateral vascular bundles. Oxycaryum cubense differs from Cyperus odoratus and Pycreus macrostachyos by having roots with long hairs; rhizomes and stolons with collateral vascular bundles; leaf blades with acute margins, and lacking Kranz structures in leaves and scapes. Anatomic characters such as the presence of large air canals principally in the roots, bulliform cells on the adaxial face of the leaf epidermis, hypodermis, reduced numbers of xylem vascular elements and little lignification of the cell walls of the different plant organs are considered important features in the adaptation of these amphibious plants that inhabit temporary lakes in the semi-arid region of Bahia state.

Visando elucidar aspectos da tolerância à hipoxia, plantas de Cecropia pachystachya foram submetidas a 30 dias de inundação. O crescimento e desenvolvimento, a condutância estomática, a fotossíntese e a morfo-anatomia foram avaliadas. A taxa de crescimento relativo (TCR) da raiz e do caule foi inferior em plantas alagadas, não havendo diferenças nesta taxa para as folhas e para a planta inteira. A não variação na TCR das folhas pode ter sido em função da maior esclerofilia foliar das plantas alagadas, que apresentaram menor área. A condutância estomática e a taxa fotossintética diminuíram nas plantas submetidas ao alagamento. Foram observadas alterações morfo-anatômicas em caules e principalmente em raízes de plantas alagadas. A análise dos resultados indica que a tolerância desta espécie a períodos de inundação está relacionada à sua capacidade de manter uma satisfatória produção energética. A manutenção de um balanço energético positivo possibilita que mesmo sob estresse, com queda na taxa fotossintética, as plantas desta espécie apresentem uma considerável TCR. Portanto, C. pachystachya pode ser forte competidora em áreas sujeitas ao alagamento.To elucidate certain aspects of hypoxia tolerance in Cecropia pachystachya, plants were submitted to 30 days of flooding. Growth and development, stomatal conductance, photosynthetic rates and morpho-anatomy were studied. Root and stem relative growth rates (RGR) were lower in flooded plants. There was no difference in leaf RGR and whole plant RGR. The maintenance of leaf RGR is possibly related to greater sclerophylly in flooded plants. Stomatal conductance and photosynthetic rate decreased due to flooding. Stems and roots, especially the latter, showed morpho-anatomical alterations in flooded plants. The results so far suggest that flood tolerance in C. pachystachya is related to the capacity to maintain satisfactory energy production. The maintenance of a positive energy balance allows this species to maintain a substantial RGR, even under stress with a lower photosynthetic rate. Therefore C. pachystachya may be a strong competitor in flooded areas.

This is among the first studies that associate anatomical characteristics to the environment in the transition region between the two largest phytogeographic domains of South America. We aimed to analyze the leaf anatomy of 22 plant species occurring in the Amazonian savanna in the state of Mato Grosso, Brazil, with the purpose of identifying key characters that show adaptive species strategies in their natural environments. Our hypothesis was that species typical of forest habitats would not present xeromorphic characteristics, while species typical of savanna habitats would present such characteristics. We fixed the samples in FAA 50 , 1 1 FAA 50 (Formaldehyde, Acetic acid and ethyl alcohol). that were stored in alcohol 70%, later they were free-hand cut with a razor blade and stained with astra blue and basic fuchsin. For the analysis of the leaf epidermis, we used the Jeffrey modified method of separation. Characteristics such as thick cuticle, epidermis with thickened wall and straight, presence of silica in the epidermis, tector trichomes, hypostomatic leaves, stomatic crests, dorsiventral mesophyll, presence of collenchyma and vascular bundles were associated with adaptive strategies of the plants to the environment of Amazonian savanna. The anatomic characters presented here are of great importance for the species that live in savanna environments, demonstrating plasticity and contributing to the protection of the leaves to the diverse biotic and abiotic factors to which they are subject, ensuring thus the survival of the species. We demonstrate that plant species structure of Amazonian savanna is most likely shaped by environment determinism, and this fact has implications on how we expect such plants evolve in a climate changing world. [ABSTRACT FROM AUTHOR]

The wood anatomy of the root, stem (base, middle, top) and branch of Anadenanthera peregrina, Copaifera langsdorffii, Handroanthus ochraceus, Ocotea corymbosa and Xylopia aromatica growing naturally in the Brazilian Cerrado is investigated. The important findings are correlated with hydraulic architecture and mechanical requirements. The presence of hydraulic bottlenecks (also referred to as hydraulic constrictions) is evident in the transition from root to stem, but no such transition is observed from stem to branch in other four species except for Xylopia aromatica. Compared with solitary vessels, proportion of multiple vessels is higher in the roots of Anadenanthera peregrina and Copaifera langsdorffii, as well as in the roots and stem-base of Xylopia aromatica indicating a tendency toward higher safety of roots from embolism as compared to the stem. Dimensions of rays, fibers and dry biomass percentage did not clearly show variations in these cells to influence the mechanical strength. Besides reducing hydraulic conductivity, decrease in vessel diameter from the root to the stem base may also impact mechanical strength by reducing empty spaces (vessel lumen). We concluded that the wood of the stem base of the species investigated shows mechanism to safeguard from air embolism by producing narrower vessels, which can protect the main stem from constant loss of conductivity. [ABSTRACT FROM AUTHOR]

The pollution of water bodies with heavy metals is generating increasing concern worldwide, and among those heavy metals, cadmium is one of the most toxic elements released into the environment. The present study aimed to evaluate the anatomical and physiological modifications adopted by the water hyacinth (Eichhornia crassipes) under cadmium contamination. The plants were grown in Hoagland solution in a greenhouse at five cadmium levels: 0.00, 3.5, 7.0, 14.0, and 28.0 µM. The net photosynthesis, stomatal conductance, transpiration rate, Ci/Ca ratio, antioxidant system enzymes activity, and anatomical traits in plant roots and leaves were evaluated. The plants exhibited increased photosynthesis, stomatal conductance, transpiration, and Ci/Ca ratios in all treatments containing cadmium. Antioxidant system enzymes displayed increased activity in the roots and leaves of plants treated with cadmium. Plants exhibited higher stomatal density and spongy parenchyma thickness under Cd contamination. The anatomical traits of the roots exhibited no evidence of toxicity or improved vascular system traits. Thus, Eichhornia crassipes demonstrated an ability to tolerate Cd by adopting changes in the anatomy, gas exchange and antioxidant system. [ABSTRACT FROM AUTHOR]

Morphological, anatomical and ecophysiological modifications caused by flooding in the growth and development of Tabebuia avellanedae Lor. ex Griseb. (Bignoniaceae) were studied and correlated with tolerance to the excess of water in the soil. Three-month-old plants, grown in a greenhouse, underwent a period of 56 days of flooding and a post-flooding period. Photosynthesis rate and growth decreased in T. avellanedae when flooding duration increased. Though not much tolerant, plant adapted itself to short flooding periods. This relative tolerance was probably due to the capacity of T. avellanedae in developing structures which lessened flooding effects and promoted internal diffusion of oxygen from the aerial part to the roots, such as stem fissures, superficial roots and hypertrophied lenticels in the roots. As there was no great variation in the internal anatomy of T. avellanedae leaves and roots, metabolic alterations might have helped in the survival of the species during flooding.Foram estudadas as modificações morfo-anatômicas e ecofisiológicas que o alagamento provoca em Tabebuia avellanedae Lor. ex Griseb. (Bignoniaceae), correlacionando-as com sua capacidade de tolerar o excesso de água no solo. Plantas com três meses de idade, crescendo em casa de vegetação, foram submetidas a 56 dias de alagamento e a um período de pós-alagamento. A taxa fotossintética e o crescimento de T. avellanedae decresceram conforme aumentou o tempo de alagamento, mas mesmo não sendo altamente tolerante, a espécie foi capaz de se adaptar a curtos períodos de alagamento. Esta relativa tolerância provavelmente se deve à capacidade apresentada por T. avellanedae de desenvolver estruturas que amenizam os efeitos do alagamento, promovendo a difusão interna de oxigênio da parte aérea para as raízes, tais como rachaduras caulinares, raízes superficiais e lenticelas hipertrofiadas nas raízes. Como não houve acentuada variação na anatomia interna de folhas e raízes de T. avellanedae, alterações metabólicas provavelmente auxiliaram na sobrevivência da espécie durante o alagamento.

The recomposition of deforested environments demands the acclimation of seedlings in nurseries. This process induces changes in physiological, anatomical, and morphological traits of plants, favouring their establishment after transplantation to the field. The present study aimed to verify the influence of full-sun acclimation on seedling hardiness. For the purpose, leaf gas-exchange, plant anatomical and morphological parameters of three tree species [ Ceiba speciosa (A. St.-Hil.) Ravenna (Malvaceae), Croton floribundus Spreng. (Euphorbiaceae), and Cecropia pachystachya Trecul (Urticaceae)], which are used for reforestation in the Brazilian Atlantic biome, were evaluated. Seedlings were grown under 40% of total PPFD (shaded control) and under full sun (acclimated) for 168 days. The acclimation process induced a higher leaf production rate in C. speciosa and C. floribundus, whereas C. pachystachya seedlings replaced their leaves quickly, irrespective of the light conditions. The newly developed leaves of all three species presented a lower area and thicker palisade parenchyma, resulting in a reduced specific leaf area. The seedlings of C. speciosa and C. pachystachya showed increases in light-saturated net photosynthesis and transpiration rates, whereas water-use efficiency generally remained unchanged in all three species. The full-sun acclimated seedlings of C. pachystachya showed a reduced relative growth rate, lower height/stem diameter (H/D) and shoot to root dry mass ratios, characteristics that may result in greater physical resistance and ability for water and nutrient uptake to support the higher transpiratory demand under full sun. The reduction of the H/D ratio also occurred in the acclimated seedlings of C. speciosa. The seedlings of C. floribundus showed few changes during acclimation, but they did not seem to be affected by excessive light. In spite of the observed differences among the three species, all of them developed hardiness characteristics, mainly related to leaf anatomy, which should favour their establishment after transplantation to the field. [ABSTRACT FROM AUTHOR]

Cattail ( Typha domingensis Pers.) can show intense growth depending on phosphorus (P) eutrophication. We verify how P enrichment and deficiency influence T. domingensis growth and the relationship with anatomical and physiological modifications. Vegetative T. domingensis plants were grown for 60 days in a modified nutrient solution in five P levels: 0, 0.20, 0.40, 0.60 and 0.80 mM. Plant growth was evaluated at the end of the experiment. Leaf fragments were collected and fixed in F.A.A.70 and sectioned in bench-top microtome. Sections were stained with safrablau solution, mounted in slides and photographed with an optical microscope. Images were evaluated in UTHSCSA-Imagetool software which was used to measure leaf tissues. Leaf gas exchanges were evaluated 30 and 60 days after the experiment started. The data were submitted to one-way ANOVA and regression analyses or means were compared using the Scott–Knott test. Plants showed more growth in a P-rich nutrient solution. T. domingensis showed different biomass partitioning under P levels, with an increasing leaf biomass allocation for higher P levels and a lower rhizome investment. For higher P levels, plants showed increased photosynthesis, stomatal conductances and transpiratory rates. However, the highest concentration promoted a decrease in these characteristics. The leaves of T. domingensis showed larger stomata, thicker palisade parenchyma and an increased phloem proportion under higher P levels. Our results suggest that the increased growth of T. domingensis in P-rich conditions may be related to increased photosynthesis; this characteristic is limited to anatomical traits such as palisade parenchyma and stomatal modifications. [ABSTRACT FROM AUTHOR]

Plantas de Sebania virgata (Cav.) Pers. (Fabaceae) cultivadas em casa de vegetação foram alagadas por 40 dias. Plantas alagadas apresentaram aumento do peso da matéria seca e comprimento, acentuadas rachaduras corticais e intumescimento cortical esponjoso em caules e raízes, raízes superficiais e raízes adventícias. É possível que a plasticidade morfo-anatômica apresentada por esta espécie esteja contribuindo para o seu estabelecimento em solos hipóxicos.Twenty days seedlings of Sesbania virgata (Cav.) Pers. (Fabaceae) cultivated in green house were flooded by forty days. Flooded plants presented increasing of dry weight and lenght, evident cortical fissures and spongy cortical swelling on the stem basis and root, superficial roots on the soil and adventitious roots. It is possible that the morpho-anatomic plasticity presented by this specie is contribuiting for its hipoxic soils stablishment.

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There are various parameters that affect tree height and may cause dwarfism. Our goal was to study the anatomical variations in the leaf and xylem structure in dwarf and normal trees of Copaifera langsdorffii and their correlation with physico-chemical properties of the soils. Trees from two spatially close but different vegetation types, transitional forest and rupestrian field, showed markedly different wood and leaf characteristics. Adult trees of C. langsdorffii show normal height (up to 25 m) in transitional forests while in the rupestrian field they show dwarfism (small trees up to 2.5 m tall). Physical soil characteristics (such as rocky crust, low water availability due to shallow soil) presumably limit root growth and affect the rate of photosynthesis, which consequently affect the extension growth of the plant. Compared to normal trees, C. langsdorffii dwarf trees are characterized by narrow vessels and a higher proportion of vessels in multiples, features of the water transport system/hydraulic structure known to prevent embolism, wider rays with a greater potential to store starch, and higher stomatal density and potential conductance index. [ABSTRACT FROM AUTHOR]

This study aims to determine whether morphoanatomical characters of the leaves of the species of Chamaecrista sect. Absus subsection Baseophyllum could be used to support an up-ranking of C. cytisoides varieties to the species level as previously defined by molecular studies. The significance of anatomical adaptive strategies to arid environments is also discussed. Standard light microscopy techniques and histochemical tests were used for both morphoanatomical and histochemical characterization of the leaves. All the species studied share a single-layered epidermis, actinodromous-camptodromous-brochidodromous type of venation, vascular bundles surrounded by layers of fibers bounded externally by a sheath of cells containing solitary crystals, enlarged tracheids at the vein endings, vascular petiole/rachis tissue with a parenchymatous pith, accessory vascular bundles, mucilage idioblasts and hypodermis in the mesophyll, colleters, and non-secretory trichomes. The position and type of stomata, type of mesophyll, number of palisade and spongy parenchyma layers, position of mucilage idioblasts in the mesophyll, and the number of accessory vascular bundles of petiole/rachis provided useful characters for discriminating the eight species of the subsect. Baseophyllum. Histochemical tests reveal the presence of total polysaccharides, pectins, mucilage and phenolic compounds in the idioblasts. Other xeromorphic characters such as thickened outer periclinal cell walls, compact mesophyll, mucilage idioblasts and hypodermis in the mesophyll may help enable the studied species to survive in exposed sunny areas. [ABSTRACT FROM AUTHOR]

The survival of plants in epiphytic environments depends on vegetative adaptations capable to defraud different stresses. Based on the structural diversity of the Orchidaceae, the current study has the objective of relating the anatomical structure of Dichaea cogniauxiana and Epidendrum secundum with the distinct environments where they live. It was expected that, despite structural similarities as strategies for resource acquisition, some peculiar variations related to the distinct light microenvironments (inside or in the edge of the nebular forest, near to "campo rupestre" area) might be found. Leaves and roots of both species were collected in a nebular forest located at a "campo rupestre" area at Serra da Piedade, Brazil), in January and February 2005. D. cogniauxiana is adhered to trunks, in sites with high atmospheric humidity and shaded, while E. secundum is located at the edge of the nebular forest, in more luminous sites. The leaves of E. secundum had thicker cuticle and higher number of stomata per area than those of D. cogniauxiana, characteristics coherent with their distinct pattern of exhibition to sun light. The suprastomatic chambers formed by the thicker cuticle may function as a barrier of resistance to water evaporation. The succulence of the leaves of E. secundum propitiates organic acids storage at night, and the storage of starch may be involved in PEP-carboxylase metabolism, both propitiating CAM mechanism. Roots with larger number of cell layers of the velamen, and specialized thick walled cortical cells (both in E. secundum) help water absorption and indicate better adaptation to an environment with intense solar radiation and a probable higher water deficit. The remarkable cell wall thickening of E. secundum exodermis can confer more efficient protection against the excess of transpiration at the border of the nebular forest. On the other hand, besides D. cogniauxiana be epiphyte, it is in a low position - in a shaded environment and with high relative humidity. Its thin thickened velamen permits the entrance of the low available light, and photosynthesis, producing oxygen and helping to avoid hypoxia condition. As features registered for D. cogniauxiana and E. secundum roots, we can depict the velamen, distinct exodermis and endodermis, and specialized thick walled cortical cells as characteristic of epiphytic plants. [ABSTRACT FROM AUTHOR]

Paspalum L. has a large number of species with a wide morphological variability and extensive geographical distribution. Species of the genus grow in very diverse habitats, from humid or aquatic environments to dry places with clay or sandy soils, frequently saline. Given the diversity of habitats where the species of Paspalum occur, foliar anatomical characters were studied in order to explain different adaptative strategies. A description of the foliar anatomy of the genus is given, and several characters are discussed in relationship to the habitat. [ABSTRACT FROM AUTHOR]

• Variations in topography and rainfall patterns shape the functional composition of tree communities. • Southern face of the Amazon biome is exposed to a severe environmental filtering. • We investigate how co-occurring species of savanna and forest respond to constraints in environmental conditions. • The leaf xeromorphism can be determined by the exposure of plants to solar radiation and local seasonality. The diversity of environments in the Neotropical region has different environmental filters on vegetation. The southern face of the Amazon is exposed to high rainfall seasonality and poor soils, which imposes a severe environmental filtering. Plants with structural and functional adaptations can occur in specific locations due to microenvironmental characteristics. We investigated how anatomical-leaf attributes of seven co-occurring species of savanna and forest formations respond to the environmental conditions of their phytophysiognomies using usual optical microscopy techniques and statistical models. The species have different strategies to support environmental conditions. Even under a more limiting rainfall regime, plants living in seasonal forests closely related with savannic areas (Cerradão area - CDA) are less endowed with xeromorphic characteristics, which we can attribute to the conditions of continuous canopy and soil, comparatively more clayey than savanna soils. The species associated with rocky outcrops more closely related to savannic habitats (Rupestrian Cerrado of Transition area - RCT) showed greater investment in thickness of epidermal cell walls and the total thickness of the central vein. These species, together with the species associated with rocky outcrops more closely related to forest habitats (Amazon Savanna on Rocky Outcrops area - ASR), demonstrated greater investment in cuticle, straight anticline walls, straight periclinal walls or straight and convex periclinal walls, epidermis thickness, parenchyma, secretory ducts, collenchyma and sclerenchymatous fibers. Our findings reveal species' different responses to environmental conditions: ASR and RCT species present a likely longer (temporal) selective process with a high investment in hydraulic safety, but RCT species showed greater xeromorphism; CDA forms a less xeromorphic microenvironment. The leaf xeromorphism is not only determined by the rainfall levels or soil fertility characteristics, but also by the degree of exposure of these plants to solar radiation and local seasonality. [ABSTRACT FROM AUTHOR]

Anatomy of vegetative parts and its ecological significance in 10 taxa of Indian maritime strand flora, namely Allmania nodiflora, Canavalia maritima, Euphorbia atoto, Halopyrum mucronatum, Indigofera uniflora, Messerchimidia argentea, Scaevola plumierii, Scaevola taccada, Sesamum prostratum and Thespesia populnea are described. [ABSTRACT FROM AUTHOR]