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Item Antioxidant system response induced by aluminum in two rice cultivars(Brazilian Journal of Plant Physiology, 2012-04) Ribeiro, Cleberson; Cambraia, José; Fonseca Júnior, Élcio Meira da; Peixoto, Paulo Henrique PereiraThe antioxidant defense system response was evaluated in two rice cultivars (Oryza sativa L.), Fernandes (CNA-1158) and Maravilha (CNA-6843-1), treated with toxic levels of aluminum. After exposure to aluminum we determined plant growth, H2O2 and O2•- contents, lipid peroxidation, antioxidant enzymes activities and ascorbate and dehydroascorbate contents. Al predominantly accumulated in roots of both cultivars but it reduced root and shoot growth only in the Maravilha cultivar. Treatment with aluminum resulted in a reduction of 84 and 60% in the levels of H2O2 in the roots of the cultivars Maravilha and Fernandes, respectively, and of 26% in the levels of O2•- only in the roots of Fernandes cultivar. Increased lipid peroxidation was observed only in the roots of the Maravilha cultivar. In general, the antioxidant enzyme activities were higher in roots and increased in the presence of aluminum, especially in the Fernandes cultivar. The levels of ascorbate were higher in leaves and increased with aluminum treatment, while dehydroascorbate decreased in roots of both cultivars after aluminum treatment. However, the ascorbate/dehydroascorbate ratio increased in the roots of both cultivars after treatment with aluminum. Ascorbate, dehydroascorbate and ascorbate/dehydroascorbate levels found here point to an efficient regeneration of ascorbate, essential for the homeostasis of cellular metabolites involved in reactive oxygen species removal by rice plants treated with aluminum. Therefore, the higher tolerance of Fernandes to aluminum relative to Maravilha cultivar may be the result of better growth of the root system and shoots, higher antioxidant enzyme activities and a best use/regeneration of ascorbate.Item Prevalência de conjuntivite adenoviral em clínica oftalmológica no município de Viçosa (MG)(Revista Brasileira de Oftalmologia, 2015-07) Rosado-Filho, Euldes Nei; Cardoso, Silvia Almeida; Marçal, Lorena Nacif; Santos, Eliziária Cardoso dos; Silva, Eduardo de Almeida Marques da; Paula, Sérgio Oliveira de; Oliveira, Leandro Licursi deAvaliar a prevalência de Adenovírus como agente etiológico da conjuntivite, em clínica médica oftalmológica especializada, em Viçosa, Minas Gerais, Brasil. Amostras da secreção conjuntival de 91 pacientes clinicamente diagnosticados com conjuntivite foram submetidos à reação em cadeia da polimerase (PCR), utilizando primers degenerados para a região codificadora do gene da proteína estrutural II. Posteriormente as amostras positivas foram submetidas a sequenciamento e genotipagem. A análise dos resultados de PCR revelou prevalência de 36,3% de Adenovírus. Não havendo distinção entre os sexos e com maior prevalência na faixa etária de 26 a 65 anos com 60,60% dos casos positivos. O sequenciamento dos casos positivos por Adenovírus revelaram a presença dos sorotipos 3, 4, 7, 8 e 34 circulante na região. No município de Viçosa, dois em cada cinco casos de conjuntivite são de etiologia adenoviral.Item Nova subspécie de Caprimulgus (Linnaeus) (Aves, Caprimulgidae) do Espírito Santo, Brasil(Revista Brasileira de Zoologia, 1995) Ribon, RômuloA population of a small and dark nightjar was discovered at Colatina, Espírito Santo, and has been identified by its voice and pattern of coloration as a new subspecies of the Pygmy Nightjar Caprimulgus hirundinaceus (Spix, 1825). This represents a considerable range expansion for this poorly known species, formerly considered endemic to the xeric "caatinga" region of Northeastern Brazil. However, other populations may exist. Colatina's birds live on exposed dark rocks with which their plumage harmonizes.Item Soybean seed galactinol synthase activity as determined by a novel colorimetric assay(Revista Brasileira de Fisiologia Vegetal, 2000) Ribeiro, Marluci; Felix, Carlos R.; Lozzi, Silene de PaulinoGalactinol synthase (GS) is a key enzyme for the biosynthesis of raffinose oligosaccharides (RO) which are the flatulence factors present in soybean seeds and several other legumes. Understanding of soybean seed GS properties is, therefore, of biotechnological interest. The GS enzyme catalyses formation of galactinol and UDP from UDP-gal and myo-inositol. This enzyme is currently assayed by an isotopic method. We have then idealized a more convenient method for GS assay based on the indirect colorimetric determination of the UDP formed which is then hydrolyzed by exogenous apyrase and the resulting Pi quantified by a modification of the colorimetric method of Fiske & SubbaRow. The color developed is stable, and the method is suitable for detection of very low GS activity. The GS activity profiles of developing soybean seeds determined by the isotopic and the colorimetric methods are closely related. The GS enzyme was partially purified (46-fold) by treatment of seed extract with MnCl2, sequential chromatographies on DEAE-Sepharose, Phenyl-Sepharose CL-4B and Q-Sepharose columns. The crude and the partially purified enzyme showed maximum activity at pH 7.0 and 50 ºC. Dithiothreitol and MnCl2 enhanced considerably the activity of the partially purified enzyme. While UDP-glc could be hydrolyzed by the enzyme at a reative activity corresponding to 49% of that calculated for UDP-gal, UDP-man and sucrose were completely ineffective as alternative substrates.Item Variação do tamanho corporal de machos de Eulaema nigrita Lepeletier (Hymenoptera, Apidae, Euglossini). Resposta materna à flutuação de recursos?(Revista Brasileira de Zoologia, 2003-06) Peruquetti, Rui CarlosIt was compared body size (measured as intertegular span) variance of trapped-males of Eulaema nigrita Lepeletier, 1841 sampled in dry (July, August and September) and wet (December, January and February) seasons of the years 1988/89 and 1994/95 in Viçosa (Minas Gerais, Brazil). It was also compared the body size variance between males and females sampled in three nests found in São Carlos (São Paulo, Brazil) and between these males and trapped ones. The smaller male (6.4 mm) was sampled in June and the bigger (8.9 mm) in July 1994, but the majority (32.3%) showed an intertegular span ranging from 7.8 to 8.0mm. The observed variance in body size was similar between males sampled in nests and trapped-males and the variance found inside a nest was similar between the sexes. However, males sampled in 1988/89 were bigger than 1994/95 males and males sampled in nests were smaller than trapped-males. The variance of the body size of males did differ between 1988/89 and 1994/95. In the first period differences between males sampled in dry or wet season was not observed, but in 1994/95 period the males sampled in dry season showed significantly greater variance in body size than males sampled in wet season. The body size variance did not differ between the wet seasons of 1988/89 and 1994/95. The body size variation, measured as the coefficient of variation in intertegular span, did not differ between males of E. nigrita (CV = 4.3%) and ground-nesting bees. These results show that the variation in body size of males of E. nigrita reflects that one found inside the nests of this bee, being similar among males and females. This variation is expected as result of ecological factors influences the nesting females. El Niño climatic events alone or in association with the lack of local food resources due to deforestation and presence of monocultures might play a role in observed body size variation. However this hypothesis is not sufficient to explain the observed body size variation inside a single nest. The absence of pressures of selection related to the females' advantages of produce large offspring perhaps contributes to the maintenance of the observed size variation. Studies regarding maternal allocation in E. nigrita may be useful to explain either the variation in body size or sex ratio found in this Neotropical bee.Item Aspectos da biologia de Euplusia violacea (Blanchard) (Hymenoptera, Apidae, Euglossini)(Revista Brasileira de Zoologia, 1997) Peruquetti, Rui Carlos; Campos, Lúcio Antônio de OliveiraNests of orchid bee Euplusia violacea (Blanchard, 1840) colleted in trap-nests and in the wood of a construction in Viçosa, Minas Gerais (20º45'30"S, 42º52'05"W), Brazil, were studied under laboratory condictions. Some aspects of the biology of these bees were observed, such as sex-ratio, development time, Iongevity and others. Some aspects of the behavior of E. violada were also studied.Item Abelhas Euglossini (Apidae) de áreas de Mata Atlântica: abundância, riqueza e aspectos biológicos(Revista Brasileira de Zoologia, 1999) Peruquetti, Rui Carlos; Campos, Lúcio Antonio de Oliveira; Coelho, Claudia Diniz Pinto; Abrantes, Célio Vicente Machado; Lisboa, Luciane Cristina de OliveiraCollection data of Euglossinae males from Parque Estadual do Rio Doce (PERD) and Viçosa, both areas with remnants of Atlantic Rain Forest (Mata Atlântica) in Minas Gerais state, Brazil are presented. Comparisons made among three fragments with different sizes and states of disturbance from Viçosa showed differences in abundance of most common species and apparently, Eulaema nigrita Lepeletir, 1841 can be an useful indicator of disturbed sites. Some populations of euglossine bees seems to be restrict to a forest fragment, there being few or no flow of individuals or species of one fragment to another, even when they are only 1 km apart. 15 species of euglossines were sampled in PERD, and the most abundant was Eulaema cingulata (Fabricius, 1804). At Viçosa, 10 species were sampled, E. nigrita was the predominant one. Methyl salicylate attracted no males at both sites, in spite of large numbers of species and individuals sampled using this bait in other regions. The majority of species and individuals were collected in the rainy season. Only 0,58% of sampled males carried orchid pollinia (Catasetum Richard, Cycnoches Lindley and Coryanthes Hook) on their bodies. Emergence data of four species of Euglossa Latreille, 1802 reared from trap nests suggest that sex ratio in Euglossini is not a constant within the tribe. A list of 57 euglossine species now known to occur in Mata Atlântica are offered.Item Live-trapping Ocelots (Leopardus pardalis): traps, baits, injuries, immobilization and costs(Biota Neotropica, 2017) Perilli, Miriam Lúcia Lages; Matushima, Eliana Reiko; Widmer, Cynthia Elisa; Azevedo, Fernando Cesar CascelliThe capture of wild animals can provide important information on community structure, population dynamics, home range size, activity patterns, habitat use, denning, social behavior and health status. The objective of this study was to describe the method of capture with details on baits, injuries, non-target captures, anesthesia and costs, to evaluate its success as part of a health evaluation program of ocelots in a Brazilian Atlantic Forest Reserve. From a total of 1,011 trap-night effort in 86 days, we had 68 capture events composed of ocelots (22%, n=15) and non-target species (78%, n = 53). We captured 10 individual ocelots in 15 capture events, corresponding to 5.7 days to capture one ocelot. Capture efficiency was 14.8 ocelots/1,000 trap-nights effort. We suggest capture methods should be selected and implemented based on the following criteria: (i) high capture efficiency; (ii) high selectivity; (iii) low injury rate; (iv) high immobilization suitability; and (v) low costs, in order to enable comparisons of studies from different research groups and from different study areas, allowing a deliberate choice of the best method.Item Efeito do alumínio sobre a absorção, o acúmulo e o fracionamento do fósforo em sorgo(Bragantia, 2008-10) Pereira, Jamil Morais; Cambraia, José; Fonseca Júnior, Élcio Meira da; Ribeiro, ClebersonO trabalho teve como objetivo estudar o efeito do Al sobre a absorção, o acúmulo e o fracionamento do P em duas cultivares de sorgo. As plantas foram expostas a níveis tóxicos de Al durante dez dias e, então, colhidas e determinados o crescimento em tamanho e produção de massa seca, os teores de Al e de P total e as diversas formas de P nas duas partes das plantas. Avaliou-se, também, o efeito do Al sobre a absorção de P pelas raízes de plantas intactas. O Al reduziu o crescimento da raiz seminal e a produção de matéria seca de raízes e parte aérea nas duas cultivares, especialmente na sensível. Os teores de Al e de P total aumentaram nas raízes, mas não foram modificados na parte aérea nas duas cultivares. A absorção de P, entretanto, decresceu na presença de Al nas duas cultivares, principalmente na sensível. O Al, de modo geral, modificou as concentrações das várias formas de P solúvel (Pi e Porg) e insolúvel (PRNA e Presidual), exceto a da forma PLIP. Algumas dessas modificações parecem ser importantes e podem estar relacionadas com o mecanismo de tolerância ao Al em sorgo.Item Valuation of methodologies for mapping oligogenic trait loci in Recombinant Inbred Lines (RILs)(Acta Scientiarum. Agronomy, 2014-01) Peixoto, Leonardo de Azevedo; Cruz, Cosme Damião; Silva, Marcia Flores ferreira da; Ferreira, AdésioThe present work aimed to compare the efficiencies of the Oligogenic Trait Mapping Method (OTMM) and Interval Method (IM) for detecting oligogenic trait loci (OTL) in Recombinant Inbred Line (RIL) populations of different sizes. Populations consisting of 200, 500 and 1,000 individuals were employed and 100 repetitions performed for each population size. Four characteristics were evaluated: C1, determined by two genes with 50 and 30% effects on expression of the characteristic; C2, governed by three genes with 50, 20 and 10% effects; C3, regulated by two genes, each with 40% effect; and C4, controlled by two genes, each with 50% effect. The IM was efficient at detecting OTL in all evaluated characteristics; however, for characteristics determined by two genes with effects between 40 and 50%, the OTMM was more efficient at detecting and localizing OTL in simulated marks. In contrast, the IM method was more efficient at detecting and localizing OTL in simulated marks when the gene effect ranged from 10 to 30%. As a result, because oligogenic characteristics are governed by genes with greater effects, the OTMM was considered the most efficient method to be used for this type of characteristic.