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41.
Laura Jaime Esperanza Mollá Almudena Fernández María A Martín-Cabrejas Francisco J López-Andréu Rosa M Esteban 《Journal of agricultural and food chemistry》2002,50(1):122-128
Onion tissues of three varieties were evaluated for dietary fiber (DF) composition. Insoluble (IDF) and soluble (SDF) dietary fibers were subjected to acid hydrolysis, and the resultant neutral sugars, uronic acids, and Klason lignin were quantified. Brown skin exhibited the highest total dietary fiber (TDF) content (65.8%) on a dry matter basis, followed by top (48.5%) and bottom (38.6%), IDF being the main fraction found. The SDF:IDF ratio decreased from inner to outer tissues. Brown skin and outer leaves byproducts appear to be the most suitable sources of DF that might be used in food product supplementation. The chemical composition reveals that cellulose and pectic polysaccharides were the main components of onion DF in all tissues, although differences between them were noticed. An increase in the uronic acids/neutral sugars ratio from inner to outer tissues was found, suggesting that the galactan side chain shows a DF solubilization role. 相似文献
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Batch experiments were carried out to examine the partitioning of an organophosphorus insecticide, methidathion, in non-amended agricultural soil and soil amended with urban sewage sludge and/or different types of surfactant. Kinetic data showed that sewage sludge significantly reduced adsorption rate, whereas amendment of the soil with the cationic surfactant tetradecyltrimethylammonium bromide (TDTMA) at 10 x CMC (critical micellar concentration) increased the adsorption rate by a factor of 10. The adsorption isotherms were evaluated using the Freundlich model. The soil adsorption capacity for methidathion was enhanced by amendment with sewage sludge and even more significantly with TDTMA at 10 x CMC or combined with sewage sludge. TDTMA conferred a high hydrophobic character to the soil, enhancing the adsorption capacity of the rather hydrophobic methidathion. The amendment of soil both with sewage sludge and TDTMA combines the increased hydrophobicity with a higher surfactant retention by organic matter, due to an increase in cation exchange capacity, which promotes even more the adsorption capacity for the insecticide. An anionic surfactant, linear alkylbenzene sulfonate, and the non-ionic Tween 80 only induced a slight modification in the kinetics and adsorption of methidathion. 相似文献
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María Socorro Serrano Pilar Fernández-Rebollo Paolo De Vita María Dolores Carbonero Antonio Trapero María Esperanza Sánchez 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(2):149-152
Phytophthora cinnamomi is an aggressive pathogen on Lupinus luteus (yellow lupin), causing root rot, wilting and death of this crop, common in oak-rangeland ecosystems ('dehesas') in south-western
Spain. The oomycete, the main cause of Quercus decline in the region, was isolated from roots of wilted lupins in the field. Artificial inoculations on four cultivars of
L. luteus reproduced the symptoms of the disease, both in pre- and post-emergence stages, recovering the pathogen from necrotic roots.
These results suggest the potential of yellow lupin as inoculum reservoir for the infection of Quercus roots. This is the first report of P. cinnamomi as root pathogen of L. luteus. 相似文献
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Laurent Philippot Cristina Abbate Antonio Bispo Thierry Chesnot Sara Hallin Philippe Lemanceau Kristina Lindström Pascal Pandard Esperanza Romero Michael Schloter Pascal Simonet Kornelia Smalla Berndt-Michael Wilke Imes Petric Fabrice Martin-Laurent 《Journal of Soils and Sediments》2010,10(7):1344-1345
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The lesser kestrel is a Globally Threatened Species which large decline has been related to recent agricultural changes in European pseudo-steppes. Irrigation is considered as one of the major threats for this and other steppe birds, but the actual effects of irrigation on foraging habitat selection have been scarcely examined. We studied the selection of traditional dry cereal farming and irrigated habitats by foraging lesser kestrels during the breeding cycle, paying especial attention to possible differences among crop types. Field margins were the scarcest but the most positively selected habitat, and different stages of cereals cultivated following traditional practices were selected depending on the breeding and agriculture cycles. Effects of irrigation were dual. While irrigated maize and other crop types were avoided, alfalfa was used in proportion to its availability and later highly selected after harvesting. Moreover, field margins in irrigated land were selected in a similar way than in traditional dry farmland. Therefore, although maintaining low-intensity farming is still the main recommendation for this species, new management options arise when social pressure makes irrigation unavoidable. Further agri-environmental schemes in these circumstances should thus promote cultivation of alfalfa with a low input of biocides while avoiding maize, together with increasing field margins, to make compatible irrigation with lesser kestrel conservation. 相似文献
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Ivana M. Rivas‐Prez María J. Fernndez‐Sanjurjo Avelino Núez‐Delgado Carmen Monterroso Felipe Macías Esperanza lvarez‐Rodríguez 《Land Degradation \u0026amp; Development》2016,27(6):1640-1649
Coal mining in areas containing pyritic materials frequently leads to a remarkable impact on the environment because of sulphide oxidation. We studied the evolution of chemical characteristics of Technosols derived from sterile materials, in a lignite mine located in As Pontes (northwest Spain), over a 20‐year period. Three plots, which had different management practices, were selected. The mine spoil was deposited randomly in two of the plots (CSP with low S concentration and CSA with high S concentration), while it was selectively managed in the other one (P206). Twenty years after the first sampling, CSA continued to show the highest acidity (pHwater 3∙7–3∙9), whereas the lowest acidity was that of P206 (pHwater 5∙0). Regarding the surface layer, C increased 1∙1% in P206, 0∙3% in CSP and 0∙2% in CSA. Nitrogen increased 1% in P206. The C/N ratio increased in all plots. Phosphorus, Ca, Mg, K and effective cation exchange capacity decreased in 2002 and experienced a slight increase in 2012. Exchangeable Al and Al saturation increased in CSP and P206 and decreased in CSA. Electric conductivity levels of Ca, Mg, Na, Al and SO42− concentrations decreased in the soil solution in all plots during the 20‐year period. Twenty years after the first monitoring, the plots that were built based on selective management of the mine spoil showed lower acidity and acidity‐derived consequences. These facts confirm the necessity of an appropriate selection of sterile materials, avoiding the placement of pyrite‐rich spoils on the surface or near‐surface zones, which is essential to facilitate proper restoration of this kind of dumping areas. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Luciano Chi Jorge Mendoza-Vega Esperanza Huerta José David Álvarez-Solís 《Communications in Soil Science and Plant Analysis》2017,48(7):741-755
The sugarcane industry in Belize is one of the main economic drivers in the country and is therefore of crucial social and environmental importance. This study evaluated the degree of sustainability of commercial sugarcane production in Northern Belize by determining soil parameters (physical and chemical) in three soil layers (0–15, 15–30 and 30–50 cm) and crop profitability relative to years of sugarcane cultivation (4–25 years since land conversion). The parameters evaluated were organic matter (OM), total nitrogen (TN), cation exchange capacity (CEC), available phosphorus (P), potassium (K), pH, dry bulk density (DBD), porosity (?), and water-filled pore space (WFPS). Field interviews were conducted to document management practices, agricultural inputs, production costs, and yield. The results showed that OM and TN in all soil layers studied and CEC in the 30–50 cm layer decreased, and were negatively correlated, with years of sugarcane cultivation. This indicates that prolonged sugarcane cropping has detrimental effects on soil fertility. There was no clear pattern with years under sugarcane cultivation for P, pH, DBD, and K. Yield levels were maintained by intensification of cultivation, e.g. high inputs and regular replanting, providing short-term benefits at the expense of deterioration of soil fertility. The benefit to cost (B:C) ratio of sugarcane production in Northern Belize was marginal for American Sugar Refinery/Belize Sugar Industries (ASR/BSI), representative of intensive agriculture; and not profitable for small-scale farmers, 1.0 and 0.63 for plantation establishment and 1.2 and 1.0 average for the following six years of ratoon, respectively. 相似文献