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31.
Henrique de Souza Luche José Antonio Gonzalez da Silva Rafael Nornberg Emilio Ghisleni Arenhardt Vanderlei da Rosa Caetano Luciano Carlos da Maia Antonio Costa de Oliveira 《Journal of Crop Science and Biotechnology》2017,20(2):73-80
In wheat, the increase of yield and stability associated traits can be achieved by combining parents containing the stay-green trait and favorable alleles for grain yield. The aim of this work was to analyze the genetic dissimilarity between wheat lines from stay-green and synchronized maturation groups and elite cultivars. Moreover, to propose promising combinations seeking the selection of high-grain yield and high bread-making quality genotypes containing stay-green trait. The experiment was conducted in a randomized block design with three replications in 2003, 2004, and 2005, using sister-lines with the presence and absence of stay-green trait and elite cultivars. Genetic variability exists among wheat strains from the synchronized stay-green maturation group and elite cultivars. Genotypes of maturation group stay-green obtained an average performance superior to the synchronized group. Crosses between stay-green lines and the CEP 29 and BRS 177 cultivars are promising in the selection of genotypes carrying the stay-green trait with high yield and bread-making quality. 相似文献
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Gueribis Faiza Zermane Nadjia Khalfi-Habess Ouassila Siafa Abderrahmane Cimmino Alessio Boari Angela Evidente Antonio 《植物病害和植物保护杂志》2019,126(5):437-446
Journal of Plant Diseases and Protection - The efficacy of four bi- and tri-cyclic sesquiterpenes, namely inuloxins A, B and C and α-costic acid, extracted from aerial parts of Dittrichia... 相似文献
34.
Supercritical fluid extraction of pesticides from a table-ready food composite of plant origin (gazpacho) 总被引:1,自引:0,他引:1
Aguilera A Brotons M Rodríguez M Valverde A 《Journal of agricultural and food chemistry》2003,51(19):5616-5621
Supercritical fluid carbon dioxide extraction (SFE) has been evaluated for the extraction of 17 organohalogen and organophosphate pesticides in gazpacho (a table-ready food composite containing crude vegetables, white bread, vegetable oil, water, and other minor components) using anhydrous magnesium sulfate as drying agent. The effects of different parameters, such as fat content in gazpacho composites, magnesium sulfate/gazpacho ratio, supercritical fluid volume, pressure, temperature, and static modifier additions, on SFE recoveries from spiked gazpacho samples have been studied. Analyses were performed by gas chromatography (GC) with flame photometric (FPD), electron capture (ECD), and mass spectrometry (MSD) detectors. In most experiments, recoveries obtained for the nonpolar organohalogen pesticides were lower than those obtained for the most polar organophosphate pesticides, but overall pesticide recoveries determined by using the optimal SFE conditions indicate that SFE could be used to determine pesticide residue levels in gazpacho. 相似文献
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Remo Bucci Andrea D Magrí Antonio L Magrí Domenico Marini Federico Marini 《Journal of agricultural and food chemistry》2002,50(3):413-418
This work has focused on discriminating extra virgin olive oils from Sabina (Lazio, Italy) by olive fruit variety (cultivar). A set of oils from five of the most widespread cultivars (Carboncella, Frantoio, Leccino, Moraiolo, and Pendolino) in this geographical area was analyzed for chemical composition using only the Official Analytical Methods, recognized for the quality control and commercial classification of this product. The obtained data set was converted into a computer-compatible format, and principal component analysis (PCA) and a method based on the Fisher F ratio were used to reduce the number of variables without a significant loss of chemical information. Then, to differentiate these samples, two supervised chemometric procedures were applied to process the experimental data: linear discriminant analysis (LDA) and artificial neural network (ANN) using the back-propagation algorithm. It was found that both of these techniques were able to generalize and correctly predict all of the samples in the test set. However, these results were obtained using 10 variables for LDA and 6 (the major fatty acid percentages, determined by a single gas chromatogram) for ANN, which, in this case, appears to provide a better prediction ability and a simpler chemical analysis. Finally, it is pointed out that, to achieve the correct authentication of all samples, the selected training set must be representative of the whole data set. 相似文献
36.
Romero-Bastida CA Flores-Huicochea E Martin-Polo MO Velazquez G Torres JA 《Journal of agricultural and food chemistry》2004,52(8):2230-2235
The effect of moisture content and film composition on biodegradability is the focus of this study. Flexible films were first characterized for the effect on water sorption isotherms of relative humidity, temperature, zein content, and the addition of the plasticizers stearic acid, poly(ethylene glycol), or etoxylated ricine oil. Zein/ethylcellulose (EC) mixture films had a behavior between that for pure zein and EC films, which had the lowest water sorption. For films with plasticizer, the lowest water sorption at 25 degrees C was observed for those with stearic acid. Biodegradability of zein/EC films, evaluated using bacterial cultures selected for their zein proteolytic activity and isolated from a local solid waste landfill and a lagoon, showed no plasticizer effect even though its effect on moisture content was significant. Large differences were observed at different film zein concentration with the highest biodegradability for 100% zein. However, biodegradability did not mimic the water sorption behavior of zein/EC mixture films. 相似文献
37.
Janaina Braga do Carmo Marisa de Cssia Piccolo Cristiano Alberto de Andrade Carlos Eduardo Pellegrino Cerri Brigitte Josefine Feigl Erclito Sousa Neto Carlos Clemente Cerri 《Soil & Tillage Research》2007,96(1-2):250-259
Anthropogenic conversion of primary forest to pasture for cattle production is still frequent in the Amazon Basin. Practices adopted by ranchers to restore productivity to degraded pasture have the potential to alter soil N availability and N gas losses from soils. We examined short-term (35 days) effects of tillage prior to pasture re-establishment on soil N availability, CO2, NO and N2O fluxes and microbial biomass C and N under degraded pasture at Nova Vida ranch, Rondônia, Brazilian Amazon. We collected soil samples and measured gas fluxes in tilled and control (non tilled pasture) 12 times at equally spaced intervals during October 2001 to quantify the effect of tillage. Maximum soil NH4+ and NO3− pools were 13.2 and 6.3 kg N ha−1 respectively after tillage compared to 0.24 and 6.3 kg N ha−1 in the control. Carbon dioxide flux ranged from 118 to 181 mg C–CO2 m2 h−1 in the control (non-tilled) and from 110 to 235 mg C–CO2 m2 h−1 when tilled. Microbial biomass C varied from 365 to 461 μg g−1 in the control and from 248 to 535 μg g−1 when tilled. The values for N2O fluxes ranged from 1.22 to 96.9 μg N m−2 h−1 in the tilled plots with a maximum 3 days after the second tilling. Variability in NO flux in the control and when tilled was consistent with previous measures of NO emissions from pasture at Nova Vida. When tilled, the NO/N2O ratio remained <1 after the first tilling suggesting that denitrification dominated N cycling. The effects of tilling on microbial parameters were less clear, except for a decrease in qCO2 and an increase in microbial biomass C/N immediately after tilling. Our results suggest that restoration of degraded pastures with tillage will lead to less C matter, at least initially. Further long-term research is needed. 相似文献
38.
Marongiu B Piras A Porcedda S Tuveri E Sanjust E Meli M Sollai F Zucca P Rescigno A 《Journal of agricultural and food chemistry》2007,55(24):10022-10027
The volatile oil of the bark of Cinnamomum zeylanicum was extracted by means of supercritical CO2 fluid extraction in different conditions of pressure and temperature. Its chemical composition was characterized by GC-MS analysis. Nineteen compounds, which in the supercritical extract represented >95% of the oil, were identified. (E)-Cinnamaldehyde (77.1%), (E)-beta-caryophyllene (6.0%), alpha-terpineol (4.4%), and eugenol (3.0%) were found to be the major constituents. The SFE oil of cinnamon was screened for its biological activity about the formation of melanin in vitro. The extract showed antityrosinase activity and was able to reduce the formation of insoluble flakes of melanin from tyrosine. The oil also delayed the browning effect in apple homogenate. (E)-Cinnamaldehyde and eugenol were found to be mainly responsible of this inhibition effect. 相似文献
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