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Juiz de Fora, Brazil

Auad A.M.,Embrapa Gado de Leite | de Carvalho C.A.,Laboratorio Of Entomologia
Ciencia Florestal | Year: 2011

The aim of this study was to conduct a survey of beetles (Coleoptera) in a silvopastoral system, estimating constancy, abundance, richness, diversity of families and seasonality, from July 2006 to June 2008. The study was carried out at the Embrapa Dairy Cattle station, in Coronel Pacheco, Minas Gerais, Brazil. The beetles were collected in Malaise traps, fortnightly, and taken to the laboratory for analysis. A total of 26 families, 294 morphospecies and 1,606 specimens were found. The Elateridae, Mordellidae, Chrysomelidae, Coccinellidae and Curculionidae families were the most abundant, rich and diverse. The Scarabaeidae and Scolytidae families were also among the most abundant, and the Cerambycidae family was among the richest, while the Bruchidae and Carabidae families presented high diversity. The largest number of individuals and morphospecies sampled occurred during the period of rain. November 2007 presented the most (n = 535 specimens) captures of any month, followed by October 2006, September 2007, March and April of 2008.

Regitano J.B.,University of Sao Paulo | Rocha W.S.D.,Embrapa Gado de Leite | Bonfleur E.J.,Federal University of Parana | Milori D.,Embrapa Instrumentacao Agropecuaria | Alleoni L.R.F.,University of Sao Paulo
Journal of Agricultural and Food Chemistry | Year: 2016

We evaluated the effects of soil water content on the retention of diuron and its residual distribution into organomineral aggregates in four Brazilian oxisols. 14C-Diuron was incubated for days at 25, 50, and 75% of maximum water-holding capacity for each soil. After 42 days, the physical fractionation method was used to obtain >150, 53-150, 20-53, 2-20, and <2 μm aggregate sizes. Diuron retention increased with increasing soil water content for all soils. At lower soil water content, diuron's retention was higher in the sandier soil. It was mostly retained in the fine (<20 μm) aggregates of sandier soil, and for clayed soils, retention was higher in the coarse aggregates (>53 μm). The sorption coefficients (Kd and Koc) generated by batch studies should be carefully used because they do not provide information about aggregation and diffusion effects on pesticides soil sorption. © 2015 American Chemical Society.

Clemente M.A.,Federal University of Juiz de fora | Scoralik M.G.,Federal University of Juiz de fora | De Azevedo Prata M.C.,Embrapa Gado de Leite | Daemon E.,Federal University of Juiz de fora
Parasitology Research | Year: 2010

The present study evaluated the acaricidal activity of essential oils from Eucalyptus citriodora and Cymbopogon nardus on non-engorged larvae of Amblyomma cajennense and Anocentor nitens. In order to carry out the study, six groups were formed, each concentration being a treatment (6.25%, 12.5%, 25%, and 50%, respectively) and also with the creation of a control group (distilled water) and a positive control (Deltametrine). For each treatment, approximately 100 larvae of these ticks were placed onto filter papers (2 × 2 cm) impregnated with the concentrations used to test. Next, the envelopes were closed bearing inside the filter paper with measurements of 6 × 6 cm. For each group, six repetitions were performed, and after 24 h live and dead larvae were counted. This procedure was carried out for two essential oils on the two species of ticks. For A. cajennense, the acaricide efficacy of E. citriodora oil was of 10.8%, 35.3%, 34.5%, and 53.1%, whereas the efficacy of C. nardus was of 0.0%, 0.0%, 0.0%, and 61.1% at concentrations of 6.25%, 12.5%, 25.0%, and 50.0%, respectively. In relation to A. nitens, the acaricide efficacy of E. citriodora oil was of 20.1%, 84.5%, 89.2%, and 100.0%, whereas the efficacy of C. nardus was of 0.0%, 90.8%, 100.0%, and 100.0% at concentrations of 6.25%, 12.5%, 25.0%, and 50.0%, respectively. The results indicate that the essential oils tested showed a promising acaricidal activity mainly on A. nitens larvae. © 2010 Springer-Verlag.

Benites F.R.G.,Embrapa Gado de Leite | Pinto C.A.B.P.,Federal University of Lavras
Crop Breeding and Applied Biotechnology | Year: 2011

Practically all potato cultivars grown in Brazil are native to Europe and not fully adapted to the tropical conditions. The purpose of this study was to estimate the genetic gains of three cycles of recurrent selection for heat tolerance in potato. The base population in this study consisted of five Brazilian and five heat-tolerant clones. In the winter of 2006 and rainy growing season of 2007 103 clones were evaluated (eight clones of the base population, 29 of the first cycle, 32 and 30 of the second and third recurrent selection cycle, respectively, and four control cultivars). The genetic gains for tuber traits in both growing seasons were 37.8 % (yield), 13.0 % (weight), 32.4 % (percent of large tubers), 0.8 % (tuber specific gravity) and 16.6 % (general tuber appearance). The percentage of physiological disorders (second-growth tubers and cracking) was also reduced by selection.

Souza-Costa D.C.,Federal University of Juiz de fora | Belo V.A.,University of Campinas | Silva P.S.,University of Campinas | Metzger I.F.,University of Sao Paulo | And 3 more authors.
International Journal of Obesity | Year: 2011

Objective: The aim of our study is to investigate whether genetic polymorphisms in the endothelial nitric oxide synthase (eNOS) gene (in the promoter region T-786 C, in exon 7 (Glu298Asp) and in intron 4 (4b/4a)) or eNOS haplotypes are associated with hypertension in obese children and adolescents. Methods: We genotyped 175 healthy (controls), 110 normotensive obese and 73 hypertensive obese children and adolescents. Genotypes were determined by Taqman allele discrimination assay and real-time PCR, and by PCR followed by fragment separation by electrophoresis. We compared the distribution of eNOS genotypes, alleles and haplotypes in the three study groups of subjects. We have also measured whole-blood nitrite concentrations.Results:The 4a4a genotype for the intron 4 polymorphism was more common in normotensive obese and hypertensive obese (P0.01). The AspAsp genotype for Glu298Asp polymorphism was less common in normotensive obese (P<0.02). No significant differences were found in allele distributions for the three eNOS polymorphisms. However, the haplotype combining the C, 4b and Glu variants for the three polymorphisms was more common in hypertensive obese than in normotensive obese or control children and adolescents (odds ratio2.28 and 2.79, respectively; 95% confidence interval: 1.31-4.31 and 1.39-5.64, respectively; both P<0.00625). This haplotype was not associated with significantly different nitrite concentrations (P<0.05).Conclusions:Our findings suggest that the eNOS haplotype, C b Glu, is associated with hypertension in obese children and adolescents. Further studies examining the possible interactions of eNOS haplotypes with environmental factors and other genetic markers involved in the development of obesity and its complications are warranted. © 2011 Macmillan Publishers Limited All rights reserved.

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