IFAPA Alameda del Obispo

Spain

IFAPA Alameda del Obispo

Spain
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Lorite I.J.,IFAPA Alameda del Obispo | Santos C.,IFAPA Alameda del Obispo | Testi L.,CSIC - Institute for Sustainable Agriculture | Fereres E.,CSIC - Institute for Sustainable Agriculture | Fereres E.,University of Cordoba, Spain
Spanish Journal of Agricultural Research | Year: 2012

Effective water management is essential to ensure the sustainability of irrigated agriculture. The accurate determination of crop water requirements is the first step in this task. This paper describes the building of a one-tree weighing lysimeter (3 × 3 m and 2.15 m depth) located in an almond (Prunus dulcis cv. Guara) orchard, inside the experimental farm "Alameda del Obispo" in Córdoba, Spain, to measure orchard evapotranspiration (ET c). Following a review on lysimetry, the description of the construction of the weighing lysimeter is provided in detail, including considerations relative to system resolution and wind effects on the measurements. Finally, some preliminary results of the evaporation and transpiration of young almond trees are presented demonstrating that lysimetry in orchards provides accurate ET c values needed to determine irrigation water requirements.


Campos-Fernandez J.,University of Cordoba, Spain | Arnal J.M.,IFAPA Alameda del Obispo | Gomez J.,IFAPA Alameda del Obispo | Lacalle N.,University of Cordoba, Spain | Dorado M.P.,University of Cordoba, Spain
Fuel | Year: 2013

The use of straight (in modified engines) or blended alcohols with fossil fuel provides an attractive alternative fuel for internal combustion engines. Moreover, alcohol can be produced by biorefineries, thus reducing the use of fossil resources. However, main achievements in this field correspond to the use of short-chain alcohols, like ethanol, while there is little experience with higher alcohols. In this work, the performance of a direct-injection diesel engine, without any modifications, fueled with 1-pentanol/diesel fuel blends has been evaluated. Blends with 10% pentanol/90% diesel fuel, 15% pentanol/85% diesel fuel, 20% pentanol/80% diesel fuel and 25% pentanol/75% diesel fuel (v/v) were tested and engine performance results were compared with those provided by neat diesel fuel. Experimental results showed insignificant engine power, brake thermal efficiency and brake-specific fuel consumption variations when the engine was fueled with the majority of the blends instead of straight diesel fuel. Moreover, statistical analysis showed no significant differences between the blends and diesel fuel (EN 590) tests. During engine starting, no difficulties were experienced and the engine performed satisfactorily on the blends throughout the entire test. On the basis of this study, pentanol/diesel fuel blends can be considered acceptable diesel fuel alternatives if exhaust emissions and long-term engine tests show acceptable results. © 2013 Elsevier Ltd. All rights reserved.


Campos-Fernandez J.,University of Cordoba, Spain | Arnal J.M.,IFAPA Alameda del Obispo | Gomez J.,IFAPA Alameda del Obispo | Dorado M.P.,University of Cordoba, Spain
Applied Energy | Year: 2012

The use of alcohols provides an attractive alternative fuel for internal combustion engines. Moreover, alcohol can be produced by biorefineries, thus reducing the consumption of fossil resources. Heretofore, research related to the use of alcohols as alternative fuels for internal combustion engines has been focused on the employment of short chain alcohols, mainly methanol and ethanol, blended with fossil fuels. Despite their adequate combustion properties, long chain alcohols like butanol or pentanol have been barely investigated. The objective of this work was to compare the short-term performance of a direct injection diesel engine fueled with different 1-butanol/diesel and 1-pentanol/diesel fuel blends, without any modifications of the engine. To gain knowledge about the implications of the use of the proposed blends, results were compared with those achieved with the use of neat diesel fuel. 1-butanol/diesel fuel blends (from 10% to 30% of 1-butanol by volume) and 1-pentanol/diesel fuel blends (from 10% to 25% of 1-pentanol by volume) were tested. Experimental results showed a slight engine power loss and an increase in brake thermal efficiency when the engine was fueled with higher alcohols blends instead of straight diesel fuel. However, some 1-butanol blends depicted a decrease in the brake specific fuel consumption compared to the use of neat diesel fuel. After using 1-butanol blends and 1-pentanol blends, no engine performance problems were visually detected. Moreover, statistical analysis showed no significant differences between tests. It can be concluded from this field trial that a diesel engine, without any modifications, can run successfully on a blend up to 30% 1-butanol/70% diesel fuel or 25% 1-pentanol/75% diesel fuel without externally apparent damage to the engine parts. Nevertheless, to recommend its use as a substitute of straight diesel fuel, long-term durability tests are needed. © 2012 Elsevier Ltd.


Salguero-Chaparro L.,IFAPA Alameda Del Obispo | Baeten V.,Walloon Agricultural Research Center | Abbas O.,Walloon Agricultural Research Center | Pena-Rodriguez F.,IFAPA Alameda Del Obispo
Journal of Food Engineering | Year: 2012

In the last years, the potential of NIRS for quantitative and qualitative analysis of olives fruits and oils has been investigated. However, limited work has been published about the on-line implementation of NIR spectroscopy in this sector. NIRS application at factory level (olive mills) is desirable. However, prior its implementation, many parameters related to the on-line spectrum acquisition, must be studied and optimised. In this paper, the influence of parameters such as focal distance and integration time has been studied. On-line spectral measurements were performed on intact olives in the spectral range of 380-1690 nm using a diode array spectrometer located on the top of a conveyor belt. The statistical criteria used to evaluate the spectral repeatability for each level of parameters considered were the standard deviation (SD) of the log (1/R) values and the root mean square statistics (RMS). Results demonstrated that for on-line control of olives in movement, spectra acquisition process was more affected by the focal distance chosen than by the integration time used. A focal distance of 13 mm and an integration time of 5 s have been defined as the optimal operational conditions. © 2012 Elsevier Ltd. All rights reserved.


Salguero-Chaparro L.,IFAPA Alameda Del Obispo | Baeten V.,Walloon Agricultural Research Center | Fernandez-Pierna J.A.,Walloon Agricultural Research Center | Pena-Rodriguez F.,IFAPA Alameda Del Obispo
Food Chemistry | Year: 2013

The acidity, moisture and fat content in intact olive fruits were determined on-line using a NIR diode array instrument, operating on a conveyor belt. Four sets of calibrations models were obtained by means of different combinations from samples collected during 2009-2010 and 2010-2011, using full-cross and external validation. Several preprocessing treatments such as derivatives and scatter correction were investigated by using the root mean square error of cross-validation (RMSECV) and prediction (RMSEP), as control parameters. The results obtained showed RMSECV values of 2.54-3.26 for moisture, 2.35-2.71 for fat content and 2.50-3.26 for acidity parameters, depending on the calibration model developed. Calibrations for moisture, fat content and acidity gave residual predictive deviation (RPD) values of 2.76, 2.37 and 1.60, respectively. Although, it is concluded that the on-line NIRS prediction results were acceptable for the three parameters measured in intact olive samples in movement, the models developed must be improved in order to increase their accuracy before final NIRS implementation at mills. © 2013 Elsevier Ltd. All rights reserved.


Castro P.,IFAPA Alameda del Obispo | Roman B.,IFAPA Alameda del Obispo | Rubio J.,IFAPA Alameda del Obispo | Die J.V.,CSIC - Institute for Sustainable Agriculture
Molecular Breeding | Year: 2012

Normalisation to a reference gene is the most common method of internally controlling for error in quantitative PCR (qPCR) experiments. Studies based on qPCR in chickpea have been carried out using potential reference genes exclusively. Inappropriate normalisation may result in the acquisition of biologically irrelevant data. We have tested the expression of 12 candidate internal control genes in 36 samples representing different organs/developmental stages, genotypes and stress conditions. The most stably expressed genes were PUBQ, GAPDH, UBQ and bHLH, whereas 18S rRNA and EF-1a showed considerable regulation. The most suitable combination of reference genes for the particular experimental sets tested is provided. To illustrate the use of chickpea reference genes, we checked the expression of a putative defence gene in two different genotypes infected with Ascochyta rabiei (Pass.) Lab. The set of reference genes presented here will enable the more accurate and reliable normalisation of qPCR results for gene expression studies in this important legume crop. Our findings can be used as a starting point for reference gene selection in experimental conditions different from those tested here. © 2011 Springer Science+Business Media B.V.


Salguero-Chaparro L.,IFAPA Alameda del Obispo | Palagos B.,IRSTEA | Pena-Rodriguez F.,IFAPA Alameda del Obispo | Roger J.M.,IRSTEA
Computers and Electronics in Agriculture | Year: 2013

The recent development of new portable devices enables the establishment of NIRS technology at industrial setting (on-line). However, the numerous existing NIRS databases based on a particular parameter, have been constructed with laboratory instruments (off-line), which have required a considerably effort in terms of time, labor and costs. For this reason, the transfer of calibrations between devices of different characteristics is a clearly crucial step. In this study, three different standardization algorithms: Slope/Bias Correction (SBC), Piecewise Direct Standardization (PDS) and Transfer by Orthogonal Projection (TOP) were tested and evaluated for transferring olives quality databases between an off-line NIRS monochromator (FOSS NIRSystem 6500) and a portable NIRS diode-array spectrometer (CORONA 45 visNIR). The results obtained showed that the use of TOP yielded the best Standard Error of Prediction (SEP) values for the fat content (1.97%) and free acidity (2.52%) parameters, while PDS for moisture content (2.24%). These results suggest that good calibration models for quality evaluation in intact olives can be obtained, based on spectral databases transferred between diverses NIRS spectrometers. © 2013 Elsevier B.V.


Salguero-Chaparro L.,IFAPA Alameda del Obispo | Pena-Rodriguez F.,IFAPA Alameda del Obispo
LWT - Food Science and Technology | Year: 2014

Visible/near-infrared calibrations were developed for the determination of the quality parameters (fat content, moisture and free acidity) of intact olive fruits. The reflectance spectra were acquired in two different instruments (diode-array versus grating monochromator based instruments). The grating monochromator based instrument was used at the laboratory (off-line analysis), whereas the portable diode-array based device was placed on top of a conveyor belt set to simulate measurements in an olive oil mill plant (on-line analysis). Partial least squares (PLS) regression and least squares support vector machine (LS-SVM) were used for the development of the calibration models. A total of 174 samples were prepared for the calibration (N=122) and validation (N=52) sets. The root mean square error of prediction (RMSEP) and the residual predictive deviation (RPD) values were better using the diode-array instrument and applying the PLS regression method for the fat content parameter while for the free acidity and moisture content, the LS-SVM algorithm gave the best results. The results obtained seems to suggest the viability of the on-line system, instead of the off-line analysis, for the determination of physicochemical composition in intact olives. © 2013 Elsevier Ltd.


Soto-Camara M.,IFAPA Alameda Del Obispo | Gaitan-Jurado A.J.,IFAPA Alameda Del Obispo | Dominguez J.,IFAPA Alameda Del Obispo
Talanta | Year: 2012

The feasibility of Near Infrared Spectroscopy to detect fungicide treatment on wheat samples was assessed. A total of 213 durum wheat samples from four different trial sites in Andalusia (southern Spain), with different agroclimatic conditions (soil, temperature, rainfall) were selected for been analyzed on VISNIR (400 nm-2500 nm) and NIR (1100 nm-2500 nm). Different mathematical pre-treatment on the signal (scatter correction and derivatives) were evaluated for their discrimination accuracies. Using MPLS, the selected models obtained 84% of well classified samples. © 2012 Elsevier B.V. All rights reserved.


Salguero-Chaparro L.,IFAPA Alameda del Obispo | Gaitan-Jurado A.J.,IFAPA Alameda del Obispo | Ortiz-Somovilla V.,IFAPA Alameda del Obispo | Pena-Rodriguez F.,IFAPA Alameda del Obispo
Food Control | Year: 2013

This study sought to assess the feasibility of using Near-Infrared Spectroscopy (NIRS) technology to detect levels of diuron herbicide in intact olives. The experimental set comprised 216 olive samples fortified with varying concentrations of diuron at values above and below the MRL (Maximum Residue Limit). A diuron-free sample set was used as control. A range of strategies was tested based on NIRS data for the construction of discriminant models using the Partial Least Squares-Discriminant Analysis (PLS-DA). The best model developed correctly classified 85.9% of samples used in the validation set by olives with a content of diuron above and below the MRL, applying a second order derivative with Multiplicative Scatter Correction (MSC). It can be concluded that the proposed reflectance NIR spectroscopy is appropriate for the quality control of herbicide diuron in intact olives. © 2012 Elsevier Ltd.

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