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Zekri N.,Mohammed V University | Zekri N.,Moulay Ismai University | Handaq N.,Moulay Ismai University | El Caidi A.,Institute of Agronomy and Veterinary Hassan II | And 2 more authors.
Research on Chemical Intermediates | Year: 2016

Essential oils proved their efficiency as natural insecticides to fight many pests of stored products and crops whereas the hydrosols have not been evaluated yet. The objective of this work is to assess the insecticidal effect of hydrosols extracted from Mentha suaveolens Ehrh. and Mentha pulegium L. toward an insect pest of citrus, Toxoptera aurantii (Homoptera, Aphididae). The extraction of hydrosols was carried out by hydro-distillation using Clevenger apparatus and then the chemical composition was identified by gas chromatography coupled with mass spectrometry. The chemical composition of two hydrosols revealed the abundance of hydrophilic and oxygenated compounds as piperitenone oxide and carvacrol. Different concentrations of each hydrosol were separately diluted in distilled water and applied topically to aphids. The results of this investigation have shown a high insecticidal effect, and the M. suaveolens hydrosol is more effective against citrus pests than that of M. pulegium L. Consequently, these natural compounds can be used in the management of aphids on citrus. © 2015 Springer Science+Business Media Dordrecht. Source

Morrison J.,McGill University | Madramootoo C.A.,McGill University | Chikhaoui M.,McGill University | Chikhaoui M.,Institute of Agronomy and Veterinary Hassan II
Canadian Journal of Civil Engineering | Year: 2014

There are few computer models that can simulate winter freeze-thaw conditions and spring snowmelt hydrology for agricultural tile drained lands. DRAINMOD, which is used widely to simulate tile drainage flows, has not been extensively applied during colder periods in eastern Canada. This study analyzes the performance of DRAINMOD for surface runoff and subsurface drainage predictions in southern Quebec during spring snowmelt. The model was tested with five years of field data. DRAINMOD was found to be adequate in predicting spring snowmelt hydrology, except for subsurface drainage at one site. It was found that soil characteristics had a major influence on model performance. Source

Morrison J.,McGill University | Madramootoo C.A.,McGill University | Chikhaoui M.,Institute of Agronomy and Veterinary Hassan II
Water Quality Research Journal of Canada | Year: 2013

Tile drainage is a widely adopted water management practice in the eastern Canadian provinces of Québec and Ontario. It aims to improve the productivity of poorly drained agricultural fields. Nevertheless, studies have also shown that subsurface drainage is a significant pollution pathway to surface water. This study was undertaken to evaluate the effect of tile drain spacing on surface runoff, subsurface drainage flows, and phosphorus (P) loss from two tile-drained agricultural fields located near Bedford, Québec. Field data were used with the DRAINMOD model, and in developed regression models in order to perform the analysis. Both DRAINMOD and the regression models showed good performance. Simulation results indicated that when lateral tile drain spacing is increased, the volume of subsurface drain flow decreases, and the volume of surface runoff increases, at sites with sandy and clay loam soils. For every 5 m increase in drain spacing, total phosphorus (TP) loads in subsurface drainage decreased by 6% at a site with sandy loam soil, and increased by 20% at a site with clay loam soil. TP loads in surface runoff increased as a result of increased drain spacing. © IWA Publishing 2013. Source

Urdanoz V.,Trabajos Catastrales S.A. | Cetin M.,Cukurova University | Kirda C.,Cukurova University | Daghari H.,University of Carthage | And 3 more authors.
Agricultural Water Management | Year: 2011

Irrigated agriculture is threatened by soil salinity in numerous arid and semiarid areas of the Mediterranean basin. The objective of this work was to quantify soil salinity through electromagnetic induction (EMI) techniques and relate it to the physical characteristics and irrigation management of four Mediterranean irrigation districts located in Morocco, Spain, Tunisia and Turkey. The volume and salinity of the main water inputs (irrigation and precipitation) and outputs (crop evapotranspiration and drainage) were measured or estimated in each district. Soil salinity (ECe) maps were obtained through electromagnetic induction surveys (ECa readings) and district-specific ECa-ECe calibrations. Gravimetric soil water content (WC) and soil saturation percentage (SP) were also measured in the soil calibration samples. The ECa-ECe calibration equations were highly significant (P<0.001) in all districts. ECa was not significantly correlated (P>0.1) with WC, and was only significantly correlated (P<0.1) with soil texture (estimated by SP) in Spain. Hence, ECa mainly depended upon ECe, so that the maps developed could be used effectively to assess soil salinity and its spatial variability. The surface-weighted average ECe values were low to moderate, and ranked the districts in the order: Tunisia (3.4dSm-1)>Morocco (2.2dSm-1)>Spain (1.4dSm-1)>Turkey (0.45dSm-1). Soil salinity was mainly affected by irrigation water salinity and irrigation efficiency. Drainage water salinity at the exit of each district was mostly affected by soil salinity and irrigation efficiency, with values very high in Tunisia (9.0dSm-1), high in Spain (4.6dSm-1), moderate in Morocco (estimated at 2.6dSm-1), and low in Turkey (1.4dSm-1). Salt loads in drainage waters, calculated from their salinity (ECdw) and volume (Q), were highest in Tunisia (very high Q and very high ECdw), intermediate in Turkey (extremely high Q and low ECdw) and lowest in Spain (very low Q and high ECdw) (there were no Q data for Morocco). Reduction of these high drainage volumes through sound irrigation management would be the most efficient way to control the off-site salt-pollution caused by these Mediterranean irrigation districts. © 2011 Elsevier B.V. Source

Bouazzama B.,University of Liege | Bouazzama B.,IRSTEA | Mailhol J.C.,Institute of Agronomy and Veterinary Hassan II | Xanthoulis D.,University of Liege | And 3 more authors.
Irrigation and Drainage | Year: 2013

Models simulating the effects of water stress on crop growth can be valuable tools for improving water management. PILOTE, an operative crop model, and CropSyst, a more sophisticated one, are compared on the basis of the simulation of silage maize (Zea maize L.) growth for 2years (2009-2010) under different water supply regimes in the semi-arid climate of Tadla (Morocco). Both based on Beer's law via the intercepted potential active radiation (IPAR) regarding dry matter accumulation, the models differ in the level of complexity describing crop development, biomass growth, root water uptake principle and consequently, in the number of input parameters. The models were calibrated on an unstressed irrigation treatment in 2009, and were validated on other stressed and unstressed treatments in 2009 and 2010. Although PILOTE required fewer input parameters and data than CropSyst, it performed similarly and often better when simulating both biomass and soil water balance. Therefore, for water management purposes only, the use of a simpler model such as PILOTE can be recommended. © 2013 John Wiley & Sons, Ltd. Source

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