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31.
Segura Carretero A Cruces-Blanco C Soriano Peña M Cortacero Ramírez S Fernández Gutiérrez A 《Journal of agricultural and food chemistry》2004,52(6):1419-1422
A test mixture of five phytohormones [naphthaleneacetic acid (NAA), naphthoxyacetic acid (NOA), indoleacetic acid (IAA), indolebutyric acid (IBA), and indolepropionic acid (IPA)] was investigated. These compounds were cleanly separated with good resolution by capillary zone electrophoresis with a UV diode array detector using 20 mM sodium phosphate buffer (pH 7.25). The lowest detection limit was obtained for IPA (0.45 mg L(-)(1) or 0.005 mg kg(-)(1)) and the highest for NAA (1.04 mg L(-)(1) or 0.014 mg kg(-)(1)). The method has been applied for tomato samples fortified with the five phytohormones using a liquid-liquid extraction procedure, obtaining recovery percentages ranging from 91 to 109.0%. 相似文献
32.
Santana Pedro Henrique Lopes Burak Diego Lang Thiengo Cássio Carlette Peçanha Anderson Lopes Neves Mirna Aparecida Mendonça Eduardo de Sá 《Journal of Soils and Sediments》2020,20(11):4103-4110
Journal of Soils and Sediments - After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for... 相似文献
33.
Robles Esperanza Ramírez Pedro Elena González Ma. de Guadalupe Sáinz Ma. Martínez Blanca Durán Angel Elena Martínez Ma. 《Water, air, and soil pollution》1999,113(1-4):217-226
Bacteriological and physico-chemical parameters of 265 samples from 39 brands sold in 5-gallon plastic and glass bottles and 2-5 L plastic containers were analyzed to determine the quality of bottled water distributed in Mexico City. Tests included fecal and total coliform counts, alkalinity, total hardness, chloride, calcium and magnesium concentrations, pH and conductivity. Correlation and cluster analyses and ANOVA were carried out, and a comparison made of the averages with the maximum permissible levels established in the Official Mexican Norms. Concerning the investigated parameters no differences (p > 0.05) between the brands were found. Physico-chemical parameters were studied and all the samples were within the permissible limits. Most samples taken from the 5-gallon containers exceeded the maximum bacteriological limits. It was concluded that the bacteriological quality of the brands studied was extremely variable. Appropriate sanitary measures, should be established to control this aspect. 相似文献
34.
B. S. Gimeno J. Peñuelas J. L. Porcuna R. A. Reinert 《Water, air, and soil pollution》1995,85(3):1521-1526
High ozone (O3) levels have been recorded in eastern Spain. A project was developed to identify the areas of elevated O3 and determine if these levels were above critical concentrations for plant damage. Thus, a network of bioindicators was established in two Autonomous Communities of Spain: Catalunya (31.930 km2) and Valencia (23.305 km2) to assess O3 phytotoxicity. Three tobacco cultivars, (Bel-W3, Bel-C and Bel-B) were used during the 1994 growing season in both Regions. In Catalunya the highest O3 phytotoxicity was recorded in coastal areas, while the phytotoxicity decreased as plants were grown further in-land. A lower O3 phytotoxicity was observed in coastal sites of the Valencia Autonomous Community, compared to Catalunya, although the O3 injury was observed downwind from Valencia city in the most resistant cultivar Bel-B. The results in the Valencian Community were difficult to interpret, since plant viruses were widely distributed, not only in indicator plants, but also in commercial crops grown in the area. The analysis of O3 concentrations, meteorological parameters and visible injury at the Catalan sites showed that high relative humidity levels could favour O3 phytotoxicity. Therefore, the interactions between O3 exposure and environmental conditions on plant response should be further studied for the establishment of sound critical levels. 相似文献
35.
García-Llatas G Cercaci L Rodriguez-Estrada MT Lagarda MJ Farré R Lercker G 《Journal of agricultural and food chemistry》2008,56(2):469-475
The effect of storage on sterol oxidation of ready-to-eat infant foods was evaluated. Two different liquid infant foods (honey or fruits flavors), prepared with milk and cereals, were stored for 0, 2, 4, 7 and 9 months at 25 degrees C. Sterol oxidation products (SOP) were isolated by cold saponification, purified by silica solid-phase extraction, and analyzed by gas chromatography (GC) and GC-mass spectrometry. beta-Sitosterol was the most representative sterol, followed by cholesterol and campesterol. No significant differences in the total and single SOP content (0.8-1 mg/kg of product) were observed with respect to storage time and type of sample; the main SOP found was 7-ketositosterol (<0.2 mg/kg of product). The extent of stigmasterol oxidation (2.9%) was higher than that of cholesterol (1.9%) and beta-sitosterol (1.4%). The type and quality of raw materials, as well as the processing conditions, seem to greatly influence SOP formation and accumulation in infant foods. 相似文献
36.
Susana Peña-Rodríguez Xabier Pontevedra-Pombal David Fernández-Calviño Teresa Taboada Manuel Arias-Estévez Antonio Martínez-Cortizas Juan Carlos Nóvoa-Muñoz Eduardo García-Rodeja 《Journal of Soils and Sediments》2012,12(4):542-555
Purpose
Volcanoes are a natural source of Hg, whose deposition can occur in neighbouring soils. This study examines the role of soil compounds in the geochemical behaviour of total Hg (Hg T ) in volcanic soils. An estimation of Hg from lithological origin is also assessed to ascertain the relevance of other sources in Hg T accumulated in volcanic soils. 相似文献37.
L. Caballero R. J. Peña L. M. Martín J. B. Alvarez 《Genetic Resources and Crop Evolution》2010,57(5):657-665
One hundred lines derived from 14 wheat landraces collected in Mexico were characterized in relation to spike and grain morphology
and HMW-glutenin subunit composition. Up to seven botanical varieties were identified among these materials based in four
morphological traits. The remaining nine morphological traits showed wide variation. The allelic variation at the Glu-1 loci was wide, although showed a clear risk of genetic erosion due to the low frequency of some alleles. These genotypes
could be used as genetic resources to improve important biotic and abiotic traits as well as to widen genetic diversity controlling
the HMW glutenin subunit composition of common wheat. 相似文献
38.
D. Arias J. Peñaloza-Ramírez O. Dorado P. Cuevas-Reyes Esaú Leyva Ana Luisa Albarrán-Lara G. Rangel-Altamirano 《Genetic Resources and Crop Evolution》2010,57(8):1227-1238
Jacaratia mexicana A. DC. (Caricaceae) is a tropical tree distributed throughout Mexico and Mesoamerica. Some evidence in Mexico indicates the
presence of an incipient domestication process in this species. Phylogeographical analyses can potentially determine contemporary
patterns of gene flow, isolation between population lineages, as well as historical processes such as population bottlenecks
or expansions on their geographical areas. In this study we reconstruct the phylogeographical patterns in populations of J. mexicana A. DC., in order to find differences between genetic variation among wild and cultivated populations utilizing chloroplast
DNA and nuclear DNA sequences. We generate a Bayesian phylogenetic tree, to estimate the divergence time between clades using
calibrated mutation rates. We also infer the demographic history of these populations using neutrality tests among wild and
cultivated accessions. We identified higher levels of haplotype and nucleotide diversity for the cpDNA and ITS types in wild
populations than in domesticated populations. These results indicate a reduction of genetic diversity derived from human selection
on domestication traits. Neutrality test suggests population expansion detected by the significant negative values of Fu’s
Fs in the cultivated populations of this specie. These process results in an excess of rare polymorphism with the fixation
of certain advantageous mutation throughout time, this implication are in accordance with the role of the strong selection
in the fruit traits of J. mexicana. The dated phylogeny constructed with BEAST program indicated a dispersion pattern for the J. mexicana ancestors across the South Pacific and South Eastern populations during the late Pliocene. Posterior dispersion and divergence
in the clades from Central Mexico and North Pacific are in agreement with the episodes of mountain-building in different regions
of Mexico. 相似文献
39.
Henry Zúñiga-Benítez Román Sánchez-Monsalve Gustavo A. Peñuela 《Water, air, and soil pollution》2018,229(10):332
This paper presents the main results obtained using the heterogeneous photocatalysis with TiO2 technology in the removal of the emerging contaminant benzophenone-3 at pilot plant scale in a cylinder parabolic solar collector. In this sense, the effects of the operational parameters, pH and catalyst concentration, were analyzed, and after the use of the response surface methodology, the conditions that, under the experimental range, conduct to a higher removal of the analyte were selected. Additionally, analysis of the total organic carbon content and the biodegradability index (relationship between BDO5 and COD) of the treated samples were carried out. In general, results allowed us to infer that this kind of treatment is effective in removing a considerable percentage of the substrate, and that it could become an effective alternative to water treatment and decontamination. 相似文献
40.