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51.
Spatial variability in grape yield and quality influenced by soil and crop nutrition characteristics
J. Arnó J. R. Rosell R. Blanco M. C. Ramos J. A. Martínez-Casasnovas 《Precision Agriculture》2012,13(3):393-410
Knowledge of spatial variability of soil fertility and plant nutrition is critical for planning and implementing site-specific
vineyard management. To better understand the key drivers behind vineyard variability, yield mapping from 2002 to 2005 and
2007 (the monitor broke down in 2006) was used to identify zones of different productive potential in a Pinot Noir field located
in Raimat (Lleida, Spain). Simultaneously, the vineyard field was sampled in 2002, 2003 and 2007, applying three different
schemes (depending on the number of target vines in different grape yield zones). The sampling carried out in 2002, which
involved different soil, topographic and crop properties (mineral contents in petiole), made it possible to evaluate the influence
of these parameters on the grape yield variability. The zones of lowest yield coincided with locations in which the nutritional
status of the crop exhibited the lowest values, particularly with respect to petiole contents of calcium and manganese. Sampling
systems adopted in 2003 and 2007 (grape quality and soil attributes) confirmed the inverse spatial correlation between grape
yield and some grape quality parameters and, more importantly, showed that the percentage of soil carbonates had a great influence
on grape quality probably due to the reduced availability of manganese in calcareous soils. Site-specific vineyard management
could therefore be considered using two different strategies: variable-rate application of foliar fertilizers to increase
the yield in areas with low production and also foliar or soil fertilizers to improve the quality specifications in some areas. 相似文献
52.
Juliano Ferreira Fernandes de Souza Eduardo Raposo Monteiro Daniela Campagnol Renata Conti Ramos Antonio Manoel Ferreira Frasson 《Journal of Equine Veterinary Science》2012
This study aimed to evaluate the effects of a constant rate infusion (CRI) of xylazine or xylazine in combination with lidocaine on nociception, sedation, and physiologic values in horses. Six horses were given intravenous (IV) administration of a loading dose (LD) of 0.55 mg/kg of xylazine followed by a CRI of 1.1 mg/kg/hr. The horses were randomly assigned to receive three treatments, on different occasions, administered 10 minutes after initiation of the xylazine CRI, as follows: control, physiologic saline; lidocaine low CRI (LLCRI), lidocaine (LD: 1.3 mg/kg, CRI: 0.025 mg/kg/min); and lidocaine high CRI (LHCRI), lidocaine (LD: 1.3 mg/kg, CRI: 0.05 mg/kg/min). A blinded observer assessed objective and subjective data for 50 minutes during the CRIs. In all treatments, heart and respiratory rates decreased, end-tidal carbon dioxide concentration increased, and moderate to intense sedation was observed, but no significant treatment effect was detected in these variables. Ataxia was significantly higher in LHCRI than in the control treatment at 20 minutes of infusion. Compared with baseline values, nociceptive threshold increased to as much as 79% in the control, 190% in LLCRI, and 158% in LHCRI. Nociceptive threshold was significantly higher in LLCRI (at 10 and 50 minutes) and in LHCRI (at 30 minutes) than in the control treatment. The combination of CRIs of lidocaine with xylazine produced greater increases in nociceptive threshold compared with xylazine alone. The effects of xylazine on sedation and cardiorespiratory variables were not enhanced by the coadministration of lidocaine. The potential to increase ataxia may contraindicate the clinical use of LHCRI, in combination with xylazine, in standing horses. 相似文献
53.
Jose Martin Ramos Diaz Satu Kirjoranta Seppo Tenitz Paavo A. Penttilä Ritva Serimaa Anna-Maija Lampi Kirsi Jouppila 《Journal of Cereal Science》2013
Amaranth (Amaranthus caudatus), quinoa (Chenopodium quinoa) and kañiwa (Chenopodium pallidicaule) are pseudocereals regarded as good gluten-free sources of protein and fiber. A co-rotating twin screw extruder was used to obtain corn-based extrudates containing amaranth/quinoa/kañiwa (20% of solids). Box–Behnken experimental design with three independent variables was used: water content of mass (WCM, 15–19%), screw speed (SS, 200–500 rpm) and temperature of the die (TEM, 150–170 °C). Milled and whole samples were stored in open headspace vials at 11 and 76% relative humidity (RH) for a week before being sealed and stored for 9 weeks in the dark. Hexanal content was determined by using headspace gas chromatography. Extrudates containing amaranth presented the highest sectional expansion index (SEI) (p < 0.01) while pure corn extrudates (control) presented the lowest SEI and greatest hardness (p < 0.01). SEI increased with increasing SS and decreasing WCM. In storage, whole extrudates exposed to 76% RH presented the lowest formation of hexanal. This study proved that it was possible to increase SEI by adding amaranth, quinoa and kañiwa to pure corn flour. The evaluation of lipid oxidation suggested a remarkable stability of whole extrudates after exposure to high RH. 相似文献
54.
Land degradation worldwide over several centuries has become a serious problem. This phenomenon has been accentuated in agricultural areas, where the amount of topsoil loss creates a gradual loss of farmland productivity. Ploughing is responsible for tillage erosion which causes more soil movement than natural soil creepage. In fact sediment transport is more rapid using heavy machinery than with primitive ploughs. The main aim of our research is to monitor, in detail, the sediment deposition phenomenon of eroded soil. Here the role of high resolution DEMs is essential. We develop a DEM generated from field measurements taken by GPS. The high spatial density of these measurements allows us to generate DEMs of high resolution: cell sizes of 0.5, 1 and 1.5 m. Three zones of different area are used in order to analyse the scale effects. In this study we assess precise models that represent a soil redistribution phenomenon. 相似文献
55.
Ramos S Moulay L Granado-Serrano AB Vilanova O Muguerza B Goya L Bravo L 《Journal of agricultural and food chemistry》2008,56(16):6985-6993
A new soluble cocoa fiber product (SCFP), obtained after enzymatic treatment of cocoa husks, was characterized and its potential health effects studied in an animal model of dietary-induced hypercholesterolemia. The SCFP was rich in soluble dietary fiber (DF) and antioxidant polyphenols. Consumption of a cholesterol-rich diet containing the SCFP as a source of DF resulted in lower food intake and body weight gain in comparison with control groups consuming cholesterol-free or cholesterol-rich diets with cellulose as DF. The cholesterol-rich diet caused remarkable hypercholesterolemia. However, the SCFP diminished the negative impact of the cholesterol-rich diet, buffering the decrease of high density lipoprotein-cholesterol, and the increase of total and low density lipoprotein-cholesterol levels, and lipid peroxidation (malondialdehyde levels) induced by the fatty diet. The SCFP also decreased triglyceride levels to values lower than those in the group fed the cholesterol-free diet. These results put forward the potential application of the SCFP as a dietary supplement or functional food ingredient. 相似文献
56.
L. M. Pitombo H. Cantarella A. P. C. Packer N. P. Ramos J. B. do Carmo 《Soil Use and Management》2017,33(4):583-594
Post‐harvest biomass can be used as feedstock for energy production and alter N2O emissions from the soil, which is among the main issues determining bioethanol sustainability. To assess the effects of sugarcane straw return on gas emissions, we established a field experiment in which 0, 50, 75 or 100% (0, 5.65, 8.47 and 11.30 Mg/ha dry biomass, respectively) of the crop residues (straw) was left in the field during the first two ratoon crops. As fertilizer is applied in bands to sugarcane, we also investigated the contribution of different positions to the N2O emissions within the field. There was an interactive effect between straw and inorganic fertilizer, leading to a nonlinear effect of crop residues on the fertilizer emission factor (EF). However, straw consistently reduced N2O emissions from the field, acting mainly in the unfertilized areas in the field (P < 0.05). We observed that considering the typical EF used in the literature, the N2O‐N emissions attributed to fertilizer ranged from 0.19 to 0.79 kg/ha, while the total emissions ranged from 3.3 to 5.2 kg/ha, from the highest amount of straw to the lowest. We conclude that overall, the fertilizer EF is not as relevant as the total emissions, based on this and other studies. Consequently, management practices might be more effective in improving the GHG balance than changing inorganic fertilizer use. We conclude that keeping up to 11 Mg/ha of straw with a large C:N ratio (>100:1) on site might increase sugarcane production sustainability by reducing the greenhouse gas emissions from the field. 相似文献
57.
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59.
Cardoso Daniel Barros Véras Robson Magno Liberal de Carvalho Francisco Fernando Ramos Magalhães André Luiz Rodrigues de Vasconcelos Gustavo Araújo Maciel Maria Inês Sucupira Madruga Marta Suely Urbano Stela Antas de Lima Silva Janaina 《Tropical animal health and production》2019,51(6):1515-1521
Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on... 相似文献
60.
David Ramos‐Vidales Gabriela Gmez‐Verduzco Arturo Cortes‐Cuevas Juan Carlos del Río‐García Sergio Fernndez‐Tinoco Silvestre Chrraga‐Aguilar Ernesto vila‐Gonzlez 《Journal of animal physiology and animal nutrition》2019,103(5):1484-1491
This study was performed in 360 laying Bovans White hens and aimed to evaluate the effect of Carbo‐Amino‐Phosphate‐Chelates (CAFQ) as a mineral premix and its 30% reduction by compared to inorganic trace minerals (ITM) concerning its performance, egg quality, tibia breaking strength and immunity. Sixty‐week‐old hens were assigned into three treatments with 10 replicates of 12 birds each. Treatments were as follows: (a) (100% ITM), (b) (100% CAFQ) and (c) (70% CAFQ). Based on the results obtained during 12 weeks, under the current test conditions, improved yolk colour (p < 0.05); shell breaking strength (p < 0.05); and storage time (p < 0.05) were observed in hens fed with a diet reduced by 70% in CAFQ inclusion showed similar performance behaviour and better egg breaking strength regarding with ITM, suggesting the possibility of minimizing the inclusion of trace minerals in laying hen diets improving environmental impact, in contrast to the use of inorganic sources of minerals. 相似文献