Interferência de plantas daninhas na cultura da cenoura (Daucus carota)

A cenoura é uma importante hortaliça no Brasil, cuja produtividade pode ser muito reduzida devido à interferência de plantas daninhas. O objetivo desta pesquisa foi avaliar efeitos de períodos de convivência das plantas daninhas na produtividade da cenoura cultivar Brasília e na comunidade de plantas daninhas. Os tratamentos foram constituídos de períodos crescentes de convivência ou controle das plantas daninhas. A comunidade de plantas daninhas foi avaliada quanto a número de indivíduos, matéria seca acumulada e frequência de ocorrência das espécies, e a cultura, quanto à produtividade comercial. As principais plantas daninhas foram Ageratum conyzoides, Digitaria nuda, Eleusine indica e Lepidium virginicum. A presença da comunidade de plantas daninhas durante todo o ciclo da cultura pode acarretar perdas de 94% na produtividade, evidenciando alta suscetibilidade da cenoura à interferência das plantas daninhas. Contudo, não houve período crítico de prevenção à interferência, e um único controle das plantas daninhas, entre 22 e 31 dias após a semeadura, foi suficiente para garantir a produção da cultura.

Qualitative-feed-restricted heavy swine: meat quality and morpho-histochemical characteristics of muscle fibers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Pothomorphe umbellata: Antifungal activity against strains of Trichophyton rubrum

Trichophyton rubrum is a dermatophyte, which can cause infections in human skin, hair and nail. Pothomorphe umbellata (L.) Miq. (Piperaceae) is a native Brazilian plant, in which phytochemical studies have demonstrated the presence of steroids, 4-nerolidylcatechol, sesquiterpenes and essential oils. The objective of this study was to analyze the in vitro activity of extracts and fractions of P. umbellata on resistant strains of T. rubrum. The microdilution plate method was utilized to test Tr1, H6 and Delta TruMDR2 strains of T rubrum; Delta TruMDR2 strain was obtained from H6 by TruMDR2 gene rupture, which is involved in multiple drugs resistance. The highest antifungal activity to all strains was observed for dichloromethane and hexane fractions of the 70% ethanolic extract which showed minimal inhibitory concentration (MIC) and minimal fungicide concentration (MFC) of 78.13 mu g/mL. This antifungal activity was also obtained by 70% ethanolic extract, which presented MIC and MFC of 78.13 mu g/mL to Delta TruMDR2, whereas the MIC values for Tr1 and H6 were 78.13 and 156.25 mu g/mL, respectively. Our results suggest the potential for future development of new antifungal drugs from P umbellata, especially to strains presenting multiple resistance. (C) 2012 Elsevier Masson SAS. All rights reserved.

Non-additive genetic effects on weights and performance of a Brazilian Bos taurus x Bos indicus beef composite

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inhibitory effect of essential oils against Lactobacillus rhamnosus and starter culture in fermented milk during its shelf-life period

The use of essential oils in foods has attracted great interest, due to their antagonistic action against pathogenic microorganisms. However, this action is undesirable for probiotic foods, as products containing Lactobacillus rhamnosus. The aim of the present study was to measure the sensitivity profile of L. rhamnosus and a yogurt starter culture in fermented milk, upon addition of increasing concentrations of cinnamon, clove and mint essential oils. Essential oils were prepared by steam distillation, and chemically characterised by gas chromatography-mass spectrometry (GC-MS) and determination of density. Survival curves were obtained from counts of L. rhamnosus and the starter culture (alone and in combination), upon addition of 0.04% essential oils. In parallel, titratable acidity was monitored over 28 experimental days. Minimum inhibitory concentration values, obtained using the microdilution method in Brain Heart Infusion medium, were 0.025, 0.2 and 0.4% for cinnamon, clove and mint essential oils, respectively. Cinnamon essential oil had the highest antimicrobial activity, especially against the starter culture, interfering with lactic acid production. Although viable cell counts of L. rhamnosus were lower following treatment with all 3 essential oils, relative to controls, these results were not statistically significant; in addition, cell counts remained greater than the minimum count of 10(8)CFU/mL required for a product to be considered a probiotic. Thus, although use of cinnamon essential oil in yogurt makes starter culture fermentation unfeasible, it does not prevent the application of L. rhamnosus to probiotic fermented milk. Furthermore, clove and mint essential oil caused sublethal stress to L. rhamnosus.

A NEW SPECIES of AFRICANA (NEMATODA: HETERAKIDAE) FROM LIZARDS of SOUTHERN AMAZON, BRAZIL

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morfometria e acúmulo de biomassa em palma forrageira sob doses de nitrogênio

Objetivou-se avaliar parâmetros morfológicos e de produção em Palma forrageira cv. Miúda, sob doses de adubo nitrogenado. Além disso, apontar características morfológicas que possam ser utilizadas como variáveis preditoras da massa fresca dos cladódios. O experimento foi conduzido num delineamento inteiramente casualizado, com quatro tratamentos (ausência de adubação nitrogenada, 100; 200 e 300kg/ha de nitrogênio) e quatro repetições. Não houve diferenças significativas (P>0,10) para as características morfogênicas e comprimento dos cladódios. A adubação nitrogenada exerceu efeito linear negativo para as características largura, espessura, volume e peso médio de cladódios e efeito linear positivo para número de cladódios. Houve correlação linear positiva entre a massa fresca e as características morfológicas dos cladódios. O uso da adubação nitrogenada não interfere nas características morfogênicas e na produção de biomassa da palma forrageira. O volume dos cladódios pode ser usado como variável preditora para a massa fresca dos cladódios.

Variabilidade temporal e espacial do tamanho de amostra da temperatura mínima do ar no Rio Grande do Sul, Brasil

Com o objetivo de verificar a existência de variabilidade temporal e espacial do tamanho de amostra da temperatura mínima do ar média mensal de trinta e sete municípios do Rio Grande do Sul, utilizaram-se os dados de temperatura mínima do ar do período de 1931 a 2000. Determinou-se o tamanho de amostra da temperatura mínima do ar média mensal em cada mês e município. Realizou-se análise de agrupamento dos meses e dos municípios pelo método hierárquico vizinho mais distante. Há variabilidade do tamanho de amostra (número de anos) para a estimativa da temperatura mínima do ar média mensal no Estado do Rio Grande do Sul no tempo e no espaço. Maior tamanho de amostra, no Estado do Rio Grande do Sul, é necessário nos meses de maio, junho e julho, com diminuição gradativa em direção a janeiro e dezembro. Há variabilidade do tamanho de amostra entre os municípios do Estado do Rio Grande do Sul.

Concentrações plasmáticas de progesterona em borregas lanadas e deslanadas no período de abril a novembro, no Estado de São Paulo

Objetivou-se com este trabalho o fornecimento de informações sobre o padrão de secreção da progesterona (P4) e as características de manifestação do ciclo estral em borregas lanadas e deslanadas, durante o período de abril a novembro, no Estado de São Paulo. Amostras de sangue foram coletadas da veia jugular de 12 borregas das raças Santa Inês (SI), Romney Marsh (RM) e Suffolk (SU), e as concentrações foram determinadas pelo método de radioimunoensaio utilizando-se kits comerciais. O estro foi detectado por machos vasectomizados (impregnados com tinta pó xadrez + óleo comestível na região peitoral) em 31 borregas (10 SI, 11 RM e 10 SU). O estro foi determinado pelo confronto da observação de fêmeas marcadas pelos machos vasectomizados e dos valores de concentrações plasmáticas de progesterona inferiores a 1 ng/mL. Os resultados mostraram que a maioria dos ciclos estrais foi de duração normal (14 - 19 dias) para todas as raças. A duração dos ciclos de duração normal das borregas SU foi inferior aos das borregas SI e RM, as quais não diferiram entre si. Não houve diferença entre as raças na duração dos ciclos curtos (< 14 dias) e longos (20 - 26 dias). O padrão de secreção de P4 mostrou a presença de ciclos estrais múltiplos (27 - 57 dias) indicando a incidência de ovulações silenciosas. As borregas SI encontravam-se em atividade cíclica reprodutiva apresentando valores que variaram de 0,08 a 7,36 ng/mL, enquanto que as raças RM e SU encontravam-se em atividade somente no período de abril a julho com valores que variaram de 0,13 a 7,05 ng/mL e de 0,15 a 7,30 ng/mL, respectivamente. de agosto a novembro, estas duas raças encontravam-se em anestro. Conclui-se que, em São Paulo, a raça SI não possui estacionalidade no ciclo reprodutivo como as raças RM e SU.

Controle químico do crestamento bacteriano comum do feijoeiro e seu efeito na transmissão de Xanthomonas campestris pv. phaseoli (Smith) Dye pelas sementes.

Dois ensaios foram conduzidos durante a safra das águas de 1987, no estado do Paraná, visando o controle químico do crestamento bacteriano comum do feijoeiro (Phaseolus vulgaris L.), na cultivar Rio Negro. Os produtos sulfato de estreptomicina + oxitetraciclina, oxicloreto de cobre + zineb, oxicloreto de cobre + mancozeb e oxicloreto de cobre, foram aplicados em pulverização, por três vezes, durante a safra. Foi observada baixa eficiência no controle dessa bacteriose, diante da elevada severidade do crestamento bacteriano nas folhas, alta incidência em vagens e elevada população de X. camnpestris pv. phaseoli nas sementes. Houve incremento na produtividade devido à aplicação de oxicloreto de cobre + zineb e oxicloreto de cobre + mancozeb.

Fungemia by yeasts in Brazil: occurrence and phenotypic study of strains isolated at the Public Hospital, Botucatu, São Paulo

Objective. - In this study strains of yeasts isolated from the blood of human patients were analyzed taxonomically, their virulence factors were determined and compared, and phenotypic markers were used to compare the samples with respect to phenotypic differences across the range of patients as well as between samples isotated from the same patient.Methods. - the study involved a total of 75 strains of yeast isolated from the blood of in-patients of the Public Hospital, Botucatu, S (a) over tildeo Paulo, Brazil, with a clinical profile of fungemia. The hospital wards with the largest number of fungemias were neonatal intensive care units (ICUs) (32%) followed by gastric surgery (13.4%) and pediatric wards (10.7%). After identification, the samples were analyzed for the production of phospholipase and proteinase enzymes, and biotyped according to their susceptibility to killer toxins.Results. - the most frequent species found was Candida albicans (38.7%) followed by C. parapsilosis (30.7%). In terms of enzyme production, 98.7% of the 75 samples of yeast presented a strongly positive activity for proteinase; however, 78.7% did not present any phospholipasic activity. Six different biotypes were identified, the most frequent being 511 and 888.Conclusion. In association with phenotypic methods, genetic analyses should also be made of the samples under study to help in the rational development of a wider range of preventive measures and better control of hospital-contracted infections. (c) 2005 Published by Elsevier SAS.

An evaluation of ocean color model estimates of marine primary productivity in coastal and pelagic regions across the globe

Nearly half of the earth's photosynthetically fixed carbon derives from the oceans. To determine global and region specific rates, we rely on models that estimate marine net primary productivity (NPP) thus it is essential that these models are evaluated to determine their accuracy. Here we assessed the skill of 21 ocean color models by comparing their estimates of depth-integrated NPP to 1156 in situ C-14 measurements encompassing ten marine regions including the Sargasso Sea, pelagic North Atlantic, coastal Northeast Atlantic, Black Sea, Mediterranean Sea, Arabian Sea, subtropical North Pacific, Ross Sea, West Antarctic Peninsula, and the Antarctic Polar Frontal Zone. Average model skill, as determined by root-mean square difference calculations, was lowest in the Black and Mediterranean Seas, highest in the pelagic North Atlantic and the Antarctic Polar Frontal Zone, and intermediate in the other six regions. The maximum fraction of model skill that may be attributable to uncertainties in both the input variables and in situ NPP measurements was nearly 72%. on average, the simplest depth/wavelength integrated models performed no worse than the more complex depth/wavelength resolved models. Ocean color models were not highly challenged in extreme conditions of surface chlorophyll-a and sea surface temperature, nor in high-nitrate low-chlorophyll waters. Water column depth was the primary influence on ocean color model performance such that average skill was significantly higher at depths greater than 250 m, suggesting that ocean color models are more challenged in Case-2 waters (coastal) than in Case-1 (pelagic) waters. Given that in situ chlorophyll-a data was used as input data, algorithm improvement is required to eliminate the poor performance of ocean color NPP models in Case-2 waters that are close to coastlines. Finally, ocean color chlorophyll-a algorithms are challenged by optically complex Case-2 waters, thus using satellite-derived chlorophyll-a to estimate NPP in coastal areas would likely further reduce the skill of ocean color models.

Distribution of exoantigens and a 43-kDa glycoprotein (gp43) in the yeast and mycelial forms of Paracoccidioides brasiliensis

Objective. Paracoccidioides brasiliensis antigens (strain 113) were located at ultrastructural level in both yeast and mycelial forms of the fungus. The reactivity of the sera employed was analysed. Materials and methods. Immunofluorescence and ultrastructural protein A-gold immunolabelling techniques were performed using two polyclonal antisera: one against P. brasiliensis exoantigens and the other against a 43-kDa glycoprotein (gp43). Immunoblotting assays were employed to define reactivity of these antisera with somatic and metabolic antigens of both forms of the fungus. Results. The techniques employed revealed in both yeast and mycelial forms of P. brasiliensis a similar antigenic distribution. The antigens deposits were seen within the cytoplasm, and over the cell wall of the fungus. The anti-exoantigen serum recognized several bands in both forms of the fungus. The anti-gp43 serum reacted strongly with the 43-kDa fraction and weakly with few other fractions. Conclusions. Immunocytochemical techniques suggest a protein synthesis within the cytoplasm followed by excretion through the cell wall. Similar results employing both polyclonal antisera were obtained.

Repeatability and heritability of response to superovulation in Holstein cows

The objective of this study was to estimate the relative effects of genetic and phenotypic factors on the efficacy and efficiency of superovulation for Holstein-Friesian cows reared in Brazil. A database, established by the Associacao Brasileira de Criadores de Bovinos da Raca Holandesa, consisting of a total of 5387 superovulations of 2941 cows distributed over 473 herds and sired by 690 bulls was used for the analysis. The records were analyzed by MTDFREML (Multiple Trait Derivative-Free Restricted Maximum Likelihood), using a repeatability animal model. The fixed effects included in the model were contemporaneous group (veterinarian, herd, year and season of the superovulation); number of semen doses; cow age; and superovulation order. The estimated repeatability of the number of the transferable embryos was low (0.13), and the estimated heritability was 0.03. These results indicate that environmental factors play a critical role in the response of a cow to a superovulation treatment. There is little evidence that future responses to superovulation by individual females can be predicted by previous treatment(s) or that superovulation response is an heritable trait.