RESUMO -O objetivo deste trabalho foi avaliar os efeitos da mesa gravitacional na qualidade fisiológica e sanitária de lotes de sementes de feijão-miúdo (Vigna unguiculata (L.) Walp). Após a limpeza, sementes de quatro genótipos (Amendoim, Baio, Mosqueado e Preto) foram beneficiadas em mesa de gravidade com descarga dividida em três frações: superior, intemediária e inferior. Admitiu-se como extremidade inferior, a situada no ponto mais baixo da descarga quando considerada a inclinação lateral da mesa e, como superior, a oposta. Avaliou-se a qualidade fisiológica das sementes através dos testes de germinação e vigor (envelhecimento acelerado, condutividade elétrica e teste de frio). Para avaliação da qualidade sanitária utilizou-se o método do papel filtro em gerbox (Blotter-test). Observou-se que a separação das sementes através da mesa gravitacional proporciona alterações positivas na qualidade fisiológica e sanitária dos lotes de sementes de feijão-miúdo para todos os genótipos avaliados, justificando-se assim, sua utilização no beneficiamento de sementes de feijão-miúdo.Termos para indexação: Beneficiamento, Vigna unguiculata, qualidade de sementes. PHYSIOLOGICAL AND SANITARY QUALITY OF CAWPEA SEEDS PROCESSED IN GRAVITY TABLEABSTRACT -the objective of this work was to evaluate the effect of the gravitational table in the sanitary and physiological quality in seeds lots of (Vigna unguiculata (L.) Walp). After the cleanness, seeds of four genotypes (Peanut, Bay, Mosqueado and Preto) had been submitted to the action of the gravity table with discharge divided in three fractions: superior, intermediate and inferior. It is admitted himself as inferior extremity, the situated one in the lowest point of the discharge when considered the lateral inclination of the table and, as superior, the opposing one. Physiological quality of the seeds was evaluated by germination test and vigor (accelerated aging, electric conductivity and cold test). For evaluation of the sanitary quality the blotter test was used. It was observed that the separation of the seeds through the gravitational table provided positive alterations in the physiological and sanitary quality of the lots of beans-small seeds for all the evaluated genotypes, justifying her use in the improvement of seeds of beans-small. INTRODUÇÃOO feijão-miúdo (Vigna unguiculata (L.) Walp) é uma leguminosa anual de clima subtropical e tropical que se apresenta distribuída praticamente em todo planeta (Araújo e Nunes, 1983).De origem africana, foi introduzida no Brasil pelo estado da Bahia, encontrando boas condições para sua adaptação na região nordeste. Mais tarde foi introduzido no estado de São Paulo por imigrantes norte-americanos. Sua dispersão no Brasil deu-se também através de importantes migrações como a dos colonos nordestinos para a região norte do Brasil (Bevitori et al, 1992).

Some macrophytes species show a high growth potential, colonizing large areas on aquatic environments. Cattail (Typha angustifolia L.) uncontrolled growth causes several problems to human activities and local biodiversity, but this also may lead to competition and further problems for this species itself. Thus, the objective of this study was to investigate anatomical modifications on T. angustifolia plants from different population densities, once it can help to understand its biology. Roots and leaves were collected from natural populations growing under high and low densities. These plant materials were fixed and submitted to usual plant microtechnique procedures. Slides were observed and photographed under light microscopy and images were analyzed in the UTHSCSA-Imagetool software. The experimental design was completely randomized with two treatments and ten replicates, data were submitted to one-way ANOVA and Scott-Knott test at p<0.05. Leaves from low density populations showed higher stomatal density and index. These modifications on stomatal characteristics were more evident on the leaf abaxial surface. Plants from low density populations showed thicker mesophyll and higher proportion of aerenchymal area. Roots from low density populations showed a higher proportion of the vascular cylinder. Whereas, plants from higher density populations showed greater thickness of the endodermis, exodermis, phloem and root cortex. Higher density populations showed a higher proportion of aerenchymal gaps in the root cortex. Therefore, cattail plants from populations growing under high density population show anatomical traits typical of plants under stress, which promotes the development of less functional anatomical modifications to aquatic environments.Keywords: anatomical plasticity, cattail, macrophytes, plant handling, eutrophication, stress. Características anatômicas relacionadas ao estresse em altas densidades populacionais de Typha angustifolia L. (Typhaceae)

-The objective of this work was to evaluate the effects of the population density of Typha angustifolia plants in the anatomical and physiological characteristics. Plants were collected from populations of high density (over 50% of colonization capacity) and low density (less than 50% of colonization capacity) and cultivated under controlled greenhouse conditions. Plants from both populations were grown in plastic trays containing 4 L of nutritive solution for 60 days. At the end of this period, the relative growth rate, leaf area ratio, net assimilatory rate, root/shoot ratio, leaf anatomy, root anatomy, and catalase and ascorbate peroxidase activities were evaluated. Plants from high density populations showed increased growth rate and root/shoot ratio. Low density populations showed higher values of stomatal index and density in leaves, as well as increased palisade parenchyma thickness. Root epidermis and exodermis thickness as well as the aerenchyma proportion of high density populations were reduced, these plants also showed increased vascular cylinder proportion. Only catalase activity was modified between the high and low density populations, showing increased values in low density populations. Therefore, different Typha angustifolia plants show differences in its anatomy and physiology related to its origins on high and low density conditions. High density population plants shows increased growth capacity related to lower apoplastic barriers in root and this may be related to increased nutrient uptake capacity.Keywords: macrophytes, Typha angustifolia, morphological plasticity, plant growth, ecological plant anatomy. RESUMO -O objetivo do trabalho foi avaliar os efeitos da origem em diferentes densidades populacionais de

ResumoO objetivo deste trabalho foi avaliar diferentes condições experimentais possibilitando a indicação de um protocolo para bioensaios baseado na germinação e crescimento inicial de plântulas utilizando como planta teste a alface (Lactuca sativa L.) cv. Grand Rapids, de forma a fornecer subsídios para padronização de ensaios com substâncias químicas diversas como aleloquímicos ou agentes toxicantes ambientais. Foram realizados os testes: tempo de germinação, temperatura, luminosidade, volume de solução e tamanho da placa de Petri. Para cada teste (exceto tempo de germinação), a influência causada pelas condições averiguadas foi determinada por meio de variáveis de percentagem de germinação, índice de velocidade de germinação, comprimento de raiz, biomassa fresca das plântulas e biomassa seca total. Os resultados encontrados mostraram que variações nas metodologias utilizadas alteram os resultados obtidos. Recomenda-se que os bioensaios utilizando Lactuca sativa cv. Grand Rapids sejam realizados por um período mínimo de quatro dias para as avaliações tanto de germinação quanto de crescimento inicial e as condições experimentais compreendam: temperatura de 20°C, placas iguais ou maiores a 90 mm, 0,1 mL/cipsela de volume de solução, em luz constante ou fotoperíodo de 12 horas. Palavras-chave: Ensaios vegetais; Fitotoxicidade; Lactuca sativa L.; Padronização AbstractBioassay standardization for the detection of allelopathic compounds and environmental toxicants using lettuce. The purpose of this study was to assess different experimental conditions to determine a protocol for bioassays based on seed germination and early seedling growth using lettuce (Lactuca sativa L.) cv. Grand Rapids as indicator species. This protocol aims to provide support for the standardization of assays of various chemicals such as allelochemicals and environmental toxicants. The following tests were performed: time of germination, temperature, light, solution volume and Petri dish size. For each test (except for time of germination), the influence of the conditions investigated was determined by the endpoints germination percentage, germination speed index, root length, seedling fresh weight and total dry weight. The results showed that variations in the

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