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da Rocha P.S.G.,Embrapa Clima Temperado | de Oliveira R.P.,Embrapa Clima Temperado | Scivittaro W.B.,Embrapa Clima Temperado | dos Santos U.L.,Instituto Federal Sul Riograndense
Ciencia Rural | Year: 2010

The objective of this research was to evaluate the effect of different sources of light in strawberry micropropagation, under increasing levels of BAP in culture medium. 'Sabrosa' shoots were inoculated in MS medium supplemented with 30g L-1 sucrose, 100mg L-1 myo-inositol, 7 agar g L-1 and BAP (0; 0.3; 0.6; 0.9; e 1.5mg L-1), pH 5.8. The explants were cultivated at 25+2°C, 16 hours photoperiod and 20μmol m-2 s-1. The luminosity was supplied by different sources of light (blue-EDEB 3LA1 LED, green-EDET 3LA1 LED, red-EDER 3LA3 LED, Growlux fluorescent lamp and white fluorescent lamp). The experimental design was a factorial entirely randomized (5 concentrations of BAP x 5 light sources) with six replications. The experiment was repeated in three successive subcultures of 35 days each, being evaluated the shoot number per explant and shoot height. The carotenoids and chlorophyll a and b determinations were carried out after the third subculture, independently of BAP concentration. Shoot number per explant was higher under red and green LEDs. BAP concentrations between 0.82 and 1.22mg L-1 in culture medium showed higher multiplication rate depending on the light source. Shoot length was highest in culture medium without BAP under all light sources. Shoots cultivated under red LEDs showed higher concentration of photosynthetic pigments, while those under green LEDs and Growlux light bulbs showed the lowest. Source

Almeida D.V.,Grande Rio University | Vaz B.,Instituto Federal Sul Riograndense | Azevedo Figueiredo M.,Grande Rio University | Junior A.S.V.,Grande Rio University | Marins L.F.,Grande Rio University
Aquatic Toxicology | Year: 2014

Transgenic fish models are potential alternative subjects in toxicological studies, since they can provide in vivo information on the deleterious effects of different substances. Here, we used a transgenic zebrafish (Danio rerio) lineage, which expresses a destabilized fluorescent protein (DsRED) driven by the myosin light chain promoter (Mylz2), in order to propose a new research tool for environmental biomonitoring. For validating the MYO-RED lineage, we exposed fish to the organophosphorated pesticide methyl parathion (MP). The effect of MP on fish growth was assessed by evaluating weight, length, condition factor and muscle fiber diameter. All factors suffered reduction at both tested concentrations (0.13. μM and 13. μM of MP). Similarly, fluorescence intensity decreased in a concentration-dependent manner, suggesting muscle protein catabolism. However, DsRED gene expression lowered only at the higher MP concentration. Results indicate that the MYO-RED transgenic zebrafish is an interesting model for detecting the growth-related effects of pollutants. Destabilized proteins such as reporter genes are apparently sensitive biomarkers, since effects were observed even at the lower, environmentally acceptable concentration. Therefore, this transgenic fish is a promising candidate model for sensitive, fast, and easy environmental monitoring. © 2014 Elsevier B.V. Source

Vivan G.A.,Instituto Federal Sul Riograndense | Robaina A.D.,Federal University of Santa Maria | Peiter M.X.,Federal University of Santa Maria | Parizi A.R.C.,Instituto Federal Farroupilha | And 2 more authors.
Semina:Ciencias Agrarias | Year: 2015

The climate, particularly water availability, presents itself as a limiting factor to obtain yields close to the productive potential of crops, being the major cause of interannual variability in grain production and income in different regions of Brazil. In this context, this study aims to identify and characterize the effect of water stress on the yield of soybean crops, maize and beans and on the costs, gross income and profit from these in the region of Santiago, RS. Therefore, we used the calibrated DSSAT system and validated for the conditions and cultures being studied, and used the historical period 1961-2010 to generate production data for each crop. Data were adimensionalizados building on the potential production of each culture, establishing frequency histogram for assessing the risk of production loss in respect of each crop. Later they used historical data series costs and selling prices of crops in the same study period for performing simplified economic analysis. In terms of production, bean, corn and soybeans in 65%, 50% and 41% of the years, respectively, achieved yields below 50% of the potential of these crops. In economic terms, the biggest cost; gross income and average income are associated with corn, followed by the bean crop and soybean, respectively. The three crops, soybean, corn, beans, showed significant reductions in production and consequently profit depending on water restriction. Source

Vanier N.L.,Federal University of Pelotas | Vanier N.L.,Healthy Processed Foods Research Unit | Paraginski R.T.,Federal University of Pelotas | Berrios J.D.J.,Healthy Processed Foods Research Unit | And 2 more authors.
Journal of Food Composition and Analysis | Year: 2015

Rice is a staple food for more than half of the world's population. The parboiling process is known to increase the nutritional value of milled rice, but the process darkens the grains, with a corresponding negative effect on consumer acceptability. The aim of this study was to evaluate the effects of using different concentrations of sodium bisulfite (0, 0.2, 0.4, 0.6, 0.8, 1.0%) during the soaking step of rice parboiling process on the thiamine content and technological properties of parboiled rice. Moreover, the residual sulfite content in parboiled grains was also evaluated. The lowest concentration of 0.2% sodium bisulfite was able to significantly (p<. 0.05) promote a whiter colour, a decrease in the percentage of stained grains, and an increase in the percentage of completely gelatinized grains in the parboiled rice, compared to rice without sodium bisulfite treatment. However, the use of sodium bisulfite significantly (p<. 0.05) reduced the thiamine content, which is considered a risk associated with the treatment. © 2015 Elsevier Inc. Source

D'Avila R.F.,Federal University of Pelotas | Zambiazi R.C.,Federal University of Pelotas | de Sa P.S.,Instituto Federal Sul Riograndense | Toralles R.P.,Instituto Federal Sul Riograndense
Revista Brasileira de Fruticultura | Year: 2015

The presence of cyanogenic glycoside amygdalin and prunasin, and of β-glucosidases which hydrolyze these molecules, causes potential toxicity in peach kernel by the possible hydrogen cyanide release, disabling the use of the kernel and their sub-products as foods. Until now, no data are available in the literature on the conditions of the enzymes hydrolysis present in this material. This study aimed to measure the amygdalin content, and the optimal conditions of pH, temperature and substrate concentration of β-glucosidases crude extract for the enzymatic activity. The results showed the presence of the glycoside in peach almond in levels similar to those found for other almond kernels. Regarding the activity of β-glucosidase, the enzyme showed Km and Vmax of 2.7 mmol L-1 of amygdalin and 0.1407 mmol of glicose. min-1.mg-1 of protein respectively, values that indicate lower affinity for amygdalin substrate than purified enzymes that catalyze the same reaction. The optimum pH of the enzyme was 7.0, but between 5.0, 6.0 and 8.0 high activity still occurs. The enzyme showed stability at the temperatures employed in this study, with maximum activity at 60 ° C. Thus, the use of these changes is not sufficient for enzyme inactivation and safe use of peach kernels. © 2015, Sociedade Brasileira de Fruticultura. All rights reserved. Source

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