Two microsatellite markers flanking a dominant gene for resistance to soybean cust nematode race 3

The purpose of this work was to identifymicrosatellite markers linked to a gene forresistance to Heterodera glycinesIchinohe (Soybean Cyst Nematode – SCN) insoybean cultivar Hartwig. ABC₁F₂ mapping population derivedfrom a cross between Hartwig (resistant)and the Brazilian soybean line Y23(susceptible) was used. About 200microsatellite or simple sequence repeat(SSR) primer pairs were tested in a bulkedsegregant analysis (BSA). Those thatshowed clear polymorphisms were amplifiedin the BC₁F₂ population, whichhad been previously inoculated andevaluated for resistance/susceptibility toSCN Race 3. Three SSR markers linked toSCN resistance were detected in thepopulation. Two of them, Satt 038 and Satt163, flanking a dominant resistant gene(d/a = –0.90), explained 37% of thephenotypic variance. This gene was mappedat the edge of molecular linkage group G. Broad and narrow sense heritabilities wereestimated to be 50.54% and 37.73%,respectively. A selection efficiency of91.18% was obtained with the simultaneoususe of the two markers. The identified SSRmarkers will be useful tools for assistingthe selection of homozygous genotypes andfor expediting the introgression of the SCNresistance locus from cv. Hartwig tosoybean elite cultivars.     

Ovum pick-up and in vitro maturation in spotted paca (Cuniculus paca—Linnaeus, 1766)

We tested FSHp, eCG and FSHp + eCG to establish ovum pick-up (OPU) and in vitro maturation method in spotted paca. Eight healthy adult females were subjected to each of four treatments to stimulate ovarian follicular growth. All females were subjected to a hormonal protocol using a single dose of 45 mg of injectable progesterone and single intramuscular injection of 0.075 mg d-cloprostenol on day 6. Ovarian stimulation was carried out as follows: in Group TFE (FSHp and eCG), animals were treated with a single dose of 80 mg of FSHp and 200 IU of eCG intramuscularly on day 6 after the application of progesterone; in Group TF (FSHp), they were treated with a single dose of 80 mg of FSHp intramuscularly on day 6 after application of progesterone; in Group treatment eCG, they were treated with 200 IU of eCG intramuscularly on day 6 after application of progesterone; and in Group TC (saline solution), 1 ml of saline solution was administered to control does. The OPU was performed between 22 and 26 hr after gonadotropin treatments. All recovered oocytes were placed into maturation media and incubated for 24 hr. There were no differences among the mean number of observed follicles, aspirated follicles and oocytes recovered per treatment. Oocyte maturation rates did not differ among groups, except, TF and treatment eCG oocytes had greater maturation rates than TC oocytes. In this study, gonadotropin administration failed to superovulate treated does and increase oocyte retrieval efficiency. Despite the feasibility of the procedure, further studies are needed to develop and refine hormonal protocols for oocyte recovery and in vitro maturation in this species.     

Fourier transform infrared spectroscopy and chemometric analysis of white wine polysaccharide extracts

Monovarietal white wines from Maria Gomes and Bical Portuguese Bairrada varieties were prepared according to different maceration and pectic enzyme clarification procedures. The polysaccharide-rich extracts, obtained by wine concentration, dialysis, and lyophilization, were fractionated by graded ethanol precipitation. A wide range of fractions rich in polysaccharides were obtained. Using the spectral region between 1200 and 800 cm(-)(1) of the FTIR spectra of the wine polysaccharide dry extracts, using PCA and CCA chemometric methods, it was possible to discriminate the extracts on the basis of their polysaccharide composition. Moreover, it was possible to identify the wine-making processes involved and their influence on the wine polysaccharides. Furthermore, a calibration model using a PLS1 was proposed for the quantification of mannose in the samples obtained by precipitation with 60% ethanol aqueous solutions. This information will allow an expeditious assessment and monitoring of the polysaccharide composition and modifications that occur during the wine-making processing and evolution.     

Serological evidence of West Nile virus circulation in Portugal

The circulation of West Nile virus in Portugal was assessed by serological surveys conducted during 2004-2010 in horses and birds. The detection of WNV antibodies in both species in all the years covered by the study as well as the presence of anti-WNV IgM in symptomatic horses that had not traveled outside the country, support the notion that WNV circulates in Portugal.     

The effect of bovine interferon-alpha I1 on pregnancy rate in heifers.

Bovine interferon-alpha I1 (bIFN-alpha) may be useful for enhancing fertility in sheep and cattle because it has extensive sequence homology with ovine and bovine trophoblast protein-1 and, like those proteins, extends corpus luteum lifespan. To test the effectiveness of bIFN-alpha to enhance fertility, several experiments were performed in which inseminated heifers were given i.m. injections of bIFN-alpha approximately at the time of embryo-mediated signals that result in maintenance of the corpus luteum. In Exp. 1, heifers given 20 mg of bIFN-alpha daily from d 14 to 17 tended (P less than .07) to have lower pregnancy rates at d 110 to 112 of gestation (36/75; 48% vs 43/72; 60%). Similar results were obtained in Exp. 2 when heifers received a single injection of 40 mg of bIFN-alpha or placebo at d 13 after estrus; pregnancy rates at d 42 were 39/104 (38%) for bIFN-alpha and 47/98 (48%) for placebo. In Exp. 3, heifers were given gradually increasing doses of bIFN-alpha or placebo from d 11 to 19, because such a regimen had been shown to reduce the number of heifers experiencing hyperthermia after bIFN-alpha injection. Pregnancy rates were 42/95 (44%) for bIFN-alpha and 62/111 (56%) for placebo. Across all three experiments, pregnancy rates were lower (P less than .01) for heifers treated with bIFN-alpha (117/274; 43%) than for heifers treated with placebo (152/281; 54%). In conclusion, these results demonstrate that, under the administration systems used, bIFN-alpha does not increase pregnancy rate, but rather tends to reduce it.     

Description of hydrological and erosion processes determined by applying the LISEM model in a rural catchment in southern Brazil

Purpose

Hydrosedimentological modeling is a tool that can be used to understand better important processes occurring at the catchment scale, such as runoff and sediment yield. The aim of this study was to use the Limburg Soil Erosion Model (LISEM) to describe the runoff and sediment yield during rainfall–runoff events in a small rural catchment in southern Brazil.

Materials and methods

The study was conducted in the Lajeado Ferreira Creek catchment (drainage area of 1.19 km²) where intense land use has caused a negative impact on water resources. Thirteen rainfall–runoff events that occurred in 2010 and 2011, including high-magnitude events, were used to model hydrosedimentological processes.

Results and discussion

Results

from the calibration and validation stages indicate that the model had a good performance when representing the hydrograph, including events with greater complexity. The use of a second soil layer in the model increased its efficiency, which is in accordance with the importance of subsurface flow in this catchment and its sensitivity to the physical properties of the soil, which are essential for controlling hydrosedimentological processes at the catchment scale. The simulation of sediment yield was overestimated by the model, constrained by the lack of sensitivity of the model to soil cohesion and the stability of soil aggregates. During the model calibration stage, these parameters had values different from those measured in the field.

Conclusions

The LISEM model performed well in representing runoff for events of different magnitudes. The discretization of the physical–hydrologic properties in the soil profile enabled the evaluation of the effect of subsurface impediment layers on water infiltration and runoff. The simulation was less accurate for suspended sediment concentration than for runoff. This indicates the need for further studies to either identify other factors controlling erosion and sediment yield that have not been identified by the model, or identify if the representation of the physical parameters is inadequate, especially the values of soil cohesion and aggregate stability.     

Voltammetric assay for the aging of beer

A new method for the evaluation of beer aging, based on a voltammetric analysis of beer distillates, is described. By measuring the current of both acetaldehyde and sulfite voltammetric peaks it is possible to distinguish between fresh, naturally aged, and artificially aged beers. The results obtained for the ratio of acetaldehyde and SO(2) currents correlate well with those given by an expert sensory panel. The kinetics of the combining reaction of sulfite with acetaldehyde was followed for different acetaldehyde/SO(2) molar ratios by using a programmed voltammetric procedure. The formation of an acetaldehyde-sulfite adduct is rapid, and the reaction equilibrium is reached after 30 min, which is in accordance with the results previously obtained by other methods. This voltammetric-based approach seems to be a new attractive tool for detecting chemical equilibria of the addition of sulfite to carbonyls in beer model systems.     

Automatic flow system with voltammetric detection for diacetyl monitoring during brewing process

Diacetyl can be determined by adsorptive stripping voltammetry after derivatization with o-phenylenediamine. The method may be applicable to the determination of diacetyl in different foods, being a good alternative to other analytical methods. In this work an on-line automated analytical system for diacetyl determination in beer is described. A hanging mercury drop electrode voltammetric flow detector was used, and the analyte was determined without the traditional deoxygenation procedure. The method was successfully applied to the determination of diacetyl during beer fermentation and in the final product. The automation strategy used was based on a flow network similar to those used in multicommutated flow systems, with a pervaporation unit used for diacetyl separation. The developed system was tested in real conditions in the monitoring of brewing processes. The results obtained were similar to those obtained with the usual GC-ECD methodology in the 5-600 ppb range. The analytical rate of the developed method is about 12 determinations/h.