Moussa El Jarroudi

University of Liège | ulg · Department of Environmental Sciences and Management

Crop production stands as a pivotal pillar of global food security, but its sustainability faces complex challenges from plant diseases, which pose a substantial threat to agricultural productivity. Climate change significantly alters the dynamics of plant pathogens, primarily through changes in temperature, humidity, and precipitation patterns, wh...

In regions facing water scarcity and soil salinity, mitigating these abiotic stresses is paramount for sustaining crop production. This study aimed to unravel the synergistic effects of organic matter and phosphorus management in reducing the adverse effect of saline water for irrigation on red pepper (Capsicum annuum L.) production, fruit quality,...

Entomopathogenic nematodes (EPNs) are emerging as key agents in ecological networks, exhibiting a wide range of interactions with other biotic components, in particular their symbiotic relationships with the bacteria Xenorhabdus and Photorhabdus. This comprehensive study reveals their global distribution and local benefits and highlights their hist...

Cereal production plays a major role in both animal and human diets throughout the world. However, cereal crops are vulnerable to attacks by fungal pathogens on the foliage, disrupting their biological cycle and photosynthesis, which can reduce yields by 15-20% or even 60%. Consumers are concerned about the excessive use of synthetic pesticides giv...

The COVID-19 pandemic has significantly affected various sectors, including agriculture. This study aimed to explore the perceptions of smallholder farmers in Morocco's Fez-Meknes and Marrakesh-Safi regions regarding the potential effects of the pandemic on agricultural systems and the adoption of agroecological practices during the lockdown. The f...

Remote sensing technology is vital for precision agriculture, aiding in early issue detection, resource management, and environmentally friendly practices. Recent advances in remote sensing technology and data processing have propelled unmanned aerial vehicles (UAVs) into valuable tools for obtaining detailed data on plant diseases with high spatia...

Disease severity in plant pathology is often measured by the amount of a plant or plant part that exhibits disease symptoms. This is typically assessed using a numerical scale, which allows for a standardized, convenient, and quick method of rating. These scales, known as "quantitative ordinal scales" (QOS), divide the percentage scale into a prede...

Monilinia laxa, a notorious fungal pathogen responsible for the devastating brown rot disease afflicting apples, wreaks havoc in both orchards and storage facilities, precipitating substantial economic losses. Currently, chemical methods represent the primary means of controlling this pathogen in warehouses. However, this study sought to explore an...

The use of excessive chemicals in agriculture can cause harm to the environment and human health. Sustainable agriculture systems promote agroecological practices to reduce chemical use and promote environmental and human health. However, there is a lack of data on the status of chemical use and the adoption of agroecological practices in the Fez-M...

Agroecology is an agricultural, holistic, and innovative approach, which aims to increase the effectiveness, efficiency, and sustainability of agricultural systems. This approach is very rewarding for agriculture in developing countries, mainly in arid zones where water resources are in sharp decline. In this study, we examined farmers' knowledge b...

Septoria leaf blotch (SLB) is among the most damaging foliar diseases of wheat worldwide. In this study, data for seven cropping seasons (2003–2009) at four representative wheat-growing sites in the Grand-Duchy of Luxembourg (GDL) were used to assess SLB risk on the three upper leaves (L3 to L1, L1 being the flag leaf) based on the combination of c...

Climate change (CC) is a significant concern for many climate-sensitive socioeconomic sectors, such as agriculture and food production. The current study aimed at analyzing the current vulnerability of the Moroccan agricultural sector to CC and anthropogenic impact and identifying the relevant vulnerability factors in the Beni Mellal-Khénifra regio...

The worldwide health crisis due to the COVID-19 virus since its outbreak in China has caused a complete lockdown of all government services in Morocco, including schooling, travel, borders, and other services, and highlighted the importance of agriculture in the food safety of the country. A survey was created to better understand smallholder farme...

In integrated pest management (IPM), pests are controlled when the costs of control correspond with the damage caused by a pest on a monetary scale, implying that low pest levels are left uncontrolled. Several forecast models have been developed in plant pathology to warn farmers before an epidemic occurs to allow timely control. Most of these mode...

The purpose of this work is to investigate the asymptotic properties of a stochastic version of the classical SIS epidemic model with three noises. The stochastic model studied here includes white noise, telegraph noise and Lévy noise. We established conditions for extinction in probability and in \begin{document}$ pth $\end{document} moment. We al...

Climate change is one of the major risks facing developing countries in Africa for which agriculture is a predominant part in the economy. Alterations in rainfall patterns and increasing temperatures projected by the Intergovernmental Panel on Climate Change (IPCC) could lead to a decline in agricultural production in many areas requiring significa...

In this article, we present a stochastic epidemic model of SIRI with non-linear relapse. We demonstrate the necessary and sufficient conditions for the extinction and persistence of the disease. We also investigate the existence of a stationary distribution and the ergodicity of solutions. As a particular case of our procedure, under some condition...

Die Krefelder Studie zeigte 2017 einen Rückgang der Masse von fliegenden Insekten um etwa 75% innerhalb von 27 Jahren in einem geschützten Gebiet (HALLMANN et al. 2017). Um die Rolle der Landwirtschaft besser zu verstehen, wären Vergleichsdaten von ungeschützten landwirtschaftlichen Flächen hilfreich. Die Richtlinie 2009/128/EH des Europäischen Par...

Cercospora leaf spot (CLS; caused by Cercospora beticola Sacc.) is the most widespread and damaging foliar disease of sugar beet. Early assessments of CLS risk are thus pivotal to the success of disease management and farm profitability. In this study, we propose a weather-based modelling approach for predicting infection by C. beticola in sugar be...

BACKGROUND Over the past decade, demethylation inhibitor (DMI) and succinate dehydrogenase inhibitor (SDHI) fungicides have been extensively used to control to septoria tritici blotch, caused by Zymoseptoria tritici on wheat. This has led to the development and selection of alterations in the target‐site enzymes (CYP51 and SDH, respectively). RESU...

The choice of the phyllotherm value for predicting leaf emergence under field conditions is pivotal to the success of fungicide-based disease risk management in temperate cereals. In this study, we investigated phyllotherm variability for predicting the emergence of the three uppermost leaves (i.e., three last leaves to emerge) in winter wheat and...

The choice of the phyllotherm value for predicting leaf emergence under field conditions is pivotal to the success of fungicide-based disease risk management in temperate cereals. In this study, we investigated phyllotherm variability for predicting the emergence of the three uppermost leaves (i.e., three last leaves to emerge) in winter wheat and...

During the past decade, imagery data acquired from unmanned aerial vehicles (UAVs), thanks to their high spatial, spectral, and temporal resolutions, have attracted increasing attention for discriminating healthy from diseased plants and monitoring the progress of such plant diseases in fields. Despite the well-documented usage of UAV-based hypersp...

The European commission directive EC 128/2009 calls for monitoring pests and pathogens of major crops. The monitoring data may be analysed for trends over time, including tests for a potential loss of biodiversity in the domain of plant pests and pathogens. The monitoring programs carried out in Luxembourg since 2007 provided evidence for an increa...

Theoretical description of epidemics of plant diseases is an invaluable resource for their efficient management. Here we propose a mathematical model for describing the dispersal by wind of fungal pathogens in plant populations. The dispersal of pathogen spores was modelled using a non-local diffusion equation which took into account variations in...

Theoretical description of epidemics of plant diseases is an invaluable resource for their efficient management. Here we propose a mathematical model for describing the dispersal by wind of fungal pathogens in plant populations. The dispersal of pathogen spores was modelled using a non-local diffusion equation which took into account variations in...

Predicting infections by Puccinia striiformis f. sp. tritici, with sufficient lead times, helps determine whether fungicide sprays should be applied in order to prevent the risk of wheat stripe rust (WSR) epidemics that might otherwise lead to yield loss. Despite the increasing threat of WSR to wheat production in Morocco, a model for predicting WS...

Septoria tritici blotch (STB) is among the most important crop diseases causing continuous threats to wheat production worldwide. STB epidemics are the outcome of interactions between susceptible host cultivars, favorable environmental conditions, and sufficient quantities of pathogen inoculum. Thus, to determine whether fungicide sprays should be...

Studies in plant pathology, agronomy and plant breeding requiring disease severity assessment often use a special type of ordinal scale based on defined numeric ranges (a quantitative ordinal scale). This form of the ordinal scale is generally based on the percent area with symptoms [e.g. the Horsfall-Barratt (HB) scale]. Parametric proportional od...

Studies in plant pathology, agronomy and plant breeding requiring disease severity assessment often use quantitative ordinal scales, i.e., a special type of ordinal scale that uses defined numeric ranges; a frequently used example of such a scale is the horsfall-Barratt scale. Parametric proportional odds models (POMs) may be used to analyze the ra...

This paper deals with modeling and fitting for epedimic models and their applications to the field of plants disease. For this purpose, two models are proposed that are expressed as a blend of two functions which reflect the effect of the temperature and the wetness. In addition, we provide an original method to fit the proposed models by employing...

Yellow rust epidemics caused by Puccinia striiformis f. sp. tritici were monitored in winter wheat grown without fungicides at four locations over the years 2010-2016 in the Grand Duchy of Luxembourg (GDL) and were observed at increased frequency since 2014. A total of 29 field case studies were subdivided into epidemic and non-epidemic cases based...

We study the asymptotic behavior of an incompressible viscous fluid flow in a biological body lined by a thin biological film with a cellular microstructure, varying thickness, and a heterogeneous viscosity regulated by a time random process. Letting the thickness of the film tend to zero, we derive an effective biological slip boundary condition o...

Meteorological conditions are important factors in the development of fungal diseases in winter wheat and are the main inputs of the decision support systems used to forecast disease and thus determine timing for efficacious fungicide application. This study uses the Fourier transform method (FTM) to characterize temporal patterns of meteorological...

Wheat stripe rust (caused by Puccinia striiformis f. sp. tritici) is a major threat in most wheat growing regions worldwide, which potentially causes substantial yield losses when environmental conditions are favorable. Data from 1999 to 2015 for three representative wheat-growing sites in Luxembourg were used to develop a threshold-based weather m...

Climate change will affect wheat crop production both in the main processes of plant growth and development and in the occurrences and severities of plant diseases. We assessed the potential infection periods of wheat leaf rust (WLR) in a changing climate at two climatologically different sites in Luxembourg using a threshold-based model for WLR. F...

The impact of rater bias and disease severity assessment method on hypothesis testing was studied for representative experimental designs for disease assessment using balanced and unbalanced data sets. Three assessment methods were considered: nearest percent estimates (NPEs), an amended 10% incremental scale, and the Horsfall-Barratt (H-B) scale....

Projected climate changes will affect wheat crop production both in the main processes of plant growth and development but also in the occurrences and severities of plant diseases. We assessed the potential infection periods of wheat leaf rust (WLR) at two climatologically differentsites in Luxembourg. A threshold-based model, taking hourlyvalues o...

Projected climate changes will affect wheat crop production both in the main processes of plant growth and development but also in the occurrences and severities of plant diseases. We assessed the potential infection periods of wheat leaf rust (WLR) at two climatologically differentsites in Luxembourg. A threshold-based model, taking hourlyvalues o...

Wheat stripe rust (WSR) (caused by Puccinia striiformis sp. tritici) i continues to be a major threat in most wheat growing regions of the world, with potential to inflict regular yield losses where susceptible cultivars are grown and when weather conditions are favourable. A recently isolated strain of P. striiformis sp. tritici, ‘warrior’, first...

The impact of rater bias and assessment method on hypothesis testing was studied for different experimental designs (balanced and unbalanced data sets). The assessment methods were nearest percent estimates (NPEs), the Horsfall-Barratt (H-B) scale, and an amended 10% incremental scale. Estimates of severity of Septoria leaf blotch on leaves of wint...

Wheat stripe rust (WSR) (caused by Puccinia striiformis sp. tritici) i continues to be a major threat in most wheat growing regions of the world, with potential to inflict regular yield losses where susceptible cultivars are grown and when weather conditions are favourable. A recently isolated strain of P. striiformis sp. tritici, ‘warrior’, first...

Wheat stripe rust (WSR) (caused by Puccinia striiformis sp. tritici) i continues to be a major threat in most wheat growing regions of the world, with potential to inflict regular yield losses where susceptible cultivars are grown and when weather conditions are favourable. A recently isolated strain of P. striiformis sp. tritici, ‘warrior’, first...

The main aim of this paper is to study the effect of the environmental noises in the asymptotic properties of a stochastic version of the classical SIRS epidemic model. The model studied here include white noise and telegraph noise modeled by Markovian switching. We obtained conditions for extinction both in probability one and in pth moment. We al...

Timely monitoring of plant biomass is critical for the management of forage resources in Sahelian rangelands. The estimation of annual biomass production in the Sahel is based on a simple relationship between satellite annual Normalized Difference Vegetation Index (NDVI) and in situ biomass data. This study proposes a new methodology using multi-li...

The effects of bias (over and underestimates) in estimates of disease severityon hypothesis testingusing different assessment methods wasexplored. Nearest percent estimates (NPE), the Horsfall-Barratt (H-B) scale, and two linear category scales (10% increments, with and without additional grades at low severity) were compared using simulation mo...

Wheat stripe rust (WSR) (caused by Puccinia striiformis sp. tritici) i continues to be a major threat in most wheat growing regions of the world, with potential to inflict regular yield losses where susceptible cultivars are grown and when weather conditions are favourable. A recently isolated strain of P. striiformis sp. tritici, ‘warrior’, first...

Wheat stripe rust (WSR) (caused by Puccinia striiformis sp. tritici) i continues to be a major threat in most wheat growing regions of the world, with potential to inflict regular yield losses where susceptible cultivars are grown and when weather conditions are favourable. A recently isolated strain of P. striiformis sp. tritici, ‘warrior’, first...

Assessment of disease severity is required for several purposes in plant pathology; most often the estimates are made visually. It is established that visual estimates can be inaccurate and unreliable. The ramifications of biased or imprecise estimates by raters have not been fully explored using empirical data; partly because of the logistical dif...

Methods to estimate disease severity vary in accuracy, reliability, ease of use and cost. Severity of Septoria leaf blotch (SLB, caused by Zymoseptoria graminicola) was estimated by four raters and by image analysis (assumed actual values) on individual leaves of winter wheat in order to explore accuracy and reliability of estimates, and to ascerta...

Assessment of disease severity is most often made visually, and estimates can be inaccurate. Nearest percent estimates (NPEs) of Septoria leaf blotch on leaves of winter wheat by four raters (R1-R4) assessing non-treated (NT) and fungicide-treated (FT) plots were compared to true values using Lin’s concordance correlation coefficient (ρc) on two da...

The accuracy and reliability of visual assessments of SLB severity by raters (i.e. one plant pathologist with extensive experience and three other raters trained prior to field observations using standard area diagrams and DISTRAIN) was determined by comparison with assumed actual values obtained by digital image analysis. Initially analyses were p...

Bias (over and underestimates) in estimates of disease severity, and the impact of that inaccuracy on hypothesis testing using different disease scales was explored. Nearest percent estimates (NPE), the Horsfall-Barratt (H-B) scale and four different linear category scales (5% and 10% increments, with and without additional grades at low severity)...

A decision support system (DSS) involving an approach for predicting wheat leaf rust (WLR) infection and progress based on night weather variables (i.e., air temperature, relative humidity, and rainfall) and a mechanistic model for leaf emergence and development simulation (i.e., PROCULTURE) was tested in order to schedule fungicide time spray for...

An empirical approach for simulating the infection and progress of leaf rust (caused by Puccinia triticina) during stem elongation on winter wheat was analysed for the 2000 to 2006 growing seasons. The approach was elaborated based on night weather conditions (i.e., air temperature, relative humidity and rainfall) and leaf rust occurrences. Data fr...

Tan spot caused by Drechslera tritici-repentis was identified for the first time in the Grand-Duchy of Luxembourg (GDL) in 1999 on the basis of morphological characters. In order to optimize disease control measures in this country, tillage methods, cultivar resistance, and fungicides effects were investigated during 1999-2009 in four sites. Over t...

Although small grain cereals (i.e. winter wheat) are routinely protected with two or three foliar treatments in the Grand-Duchy of Luxembourg (GDL), environmental concerns and changes in the cost-benefit ratio are likely to increase the demand for more accurate identification of spraying needs. A warning system assessing in real time the risk of pr...

Field experiments were conducted in 2010 to investigate the effect of fungicide commercial formulation, timing and dosages on the severity of these two diseases in winter wheat in Luxembourg. Different types of fungicides and fungicide combinations containing active ingredients such as triazoles and strobilurins were used in field trials including...

We investigate in this study (i) a redefinition of crop variety zonations at a spatial scale of 10x10 km, and (ii) the influence of recalibrated crop parameters on regional yield forecasting of winter wheat and grain maize in western Europe. The baseline zonation and initial crop parameter set was derived from the operational European crop growth m...

Septoria tritici is the causal agent of leaf blotch in wheat and among the most damaging fungal cereal pathogens in the humid regions of central Europe. The percentage of the leaf area colonized by S. tritici was recorded weekly between April and July every season between 2004 and 2010. A total of 11 cultivars with moderate susceptibility [ratings...

Theoretical frequencies of green area index (GAI) measurements were assessed in order to bring out the optimum frequencies for the monitoring of the senescence of winter wheat as well as the relationships be tween metrics which could be derived and the final grain yield. Several profiles of GAI decreasing curves were elaborated based on field measu...

Tan spot caused by Drechslera tritici-repentis was identified for the first time in the Grand-Duchy of Luxembourg (GDL) in 1999 on the basis of morphological characters. In order to optimise disease control measures in the GDL, tillage methods, cultivar resistance, and fungicides effects were investigated during 1999-2009 in four sites. Over this p...

Earth observation data, owing to their synoptic, timely and repetitive coverage, have been recognized as a valuable tool for crop monitoring at different levels. At the field level, the close correlation between green leaf area (GLA) during maturation and grain yield in wheat revealed that the onset and rate of senescence appeared to be important f...

Field experiments were conducted over four growing seasons to assess the relationship between fungal disease attacks and wheat grain yield in the agrometeorological part of the Belgian crop yield forecasting system (i.e., Belgian crop growth monitoring system, B-CGMS) by recalibrating the lifespan of wheat leaves (SPAN parameter). The results from...

http://www.meteo.fr/cic/meetings/2012/ERAD/prog&abs_ERAD2012.pdf

Over the 2003-2009 period, field campaigns were carried out in order to identify the main fungal diseases of winter wheat (Triticum aestivum) in the Grand-Duchy of Luxembourg. Four fungal diseases (septoria leaf blotch (SLB), wheat leaf rust (WLR), wheat powdery mildew (WPM) and fusarium head blight (FHB)) were observed and a regional-based typolog...

A large number of agrometeorological models for crop yield assessment are available with various levels of complexity and empiricism. However, the current development of models for wheat yield forecasting does not always reflect the inclusion of the loss of valuable green area and its relation to biotic and abiotic processes in production situation...

Malgré sa petite taille, le GDL est caractérisé par deux régions très contrastées en ce qui concerne les maladies cryptogamiques du blé d’hiver. Une analyse en composante principale a permis d’analyser la distribution des maladies cryptogamiques entre le Gutland et l’Oseling. La distribution des maladies cryptogamiques est significativement différe...

Over the 2003-2009 period, field campaigns were carried out in order to identify the main fungal diseases of winter wheat (Triticum aestivum) in the Grand-Duchy of Luxembourg. Four fungal diseases (septoria leaf blotch (SLB), wheat leaf rust (WLR), wheat powdery mildew (WPM) and fusarium head blight (FHB)) were observed and a regional-based typolog...

The prediction of cereal-crop yield is considered as a priority in most crop research programmes due to the relevance of food grain to feeding the world population. Today, a large number of agrometeorological models for crop yield assessment are available with various levels of complexity and empiricism. But, currently the development of wheat yiel...

A mechanistic model, PROCULTURE, based on commonly available meteorological data and assessing in real time the risk of progression of septoria leaf blotch disease on winter wheat has been developed in Belgium and the Grand-Duchy of Luxemburg (GDL) to limit fungicide use. However, the reliability of meteorological stations used for the warning syst...

Despite its small territory size, the Grand-Duchy of Luxembourg (GDL) has several microclimates that result in a variability of disease severity between the South (Gutland) and the North (Oesling). Septoria leaf blotch disease of wheat is an important disease in the GDL. Over 2003–2009, the severity was strong in Gutland (51% on average over the la...

Wetness on the leaf of crops has particular epidemiological significance because many fungal diseases affect plants only when free moisture is present on leaves. The leaf wetness sensor detects the presence of wetness on a leaf’s surface, enabling researchers and producers to forecast disease and protect plant canopies, consequently reduce the fung...

The Septoria leaf blotch prediction model PROCULTURE was used to assess the impact on simulated infection rates when using rainfall estimated by radar instead of rain gauge measurements. When comparing infection events simulated by PROCULTURE using radar- and gauge-derived data, the simulated probability of detection (POD) of infection events was h...

Yr17 resistance gene (Yr17+ cultivars) induces yellow rust resistance in wheat at the seedling stage and operates throughout the plant life. A new Yr17 pathotype that overcomes resistance to wheat stripe rust in Yr17+ cultivars was first detected in 1997 in countries neighboring Luxembourg (Bayles et al., 2000). In 1999, stripe rust was suspected t...

In the Grand-Duchy of Luxembourg (GDL), winter wheat is the most important cereal crop (14,597 ha) with an annual production of ca. 75,000 tons in 2008 (Le Portail des Statistiques du Grand Duché de Luxembourg, 2008). In the GDL, fungicide applications are an essential part of cereal crop management. Crop protection often relies on preventive fungi...

N° 642 mars 2011 Prévoir la septoriose un modèle belge au Luxembourg Modélisation et simulation prévisionnelle de la septoriose des feuilles par Proculture pour une gestion durable du blé d'hiver p h .

Re-emergence of Fusarium head blight (FHB) on wheat should be taken into account in the global management of cropped fields, especially with respect to fungicide application schemes, due to harmful toxin production. The aim of this study was to assess, in three experimental fields representative of the various topoclimatological zones of Luxembourg...

Surface wetness duration (SWD) is an important factor influencing the occurrence of winter wheat disease epidemiology. For this reason SWD is extremely significant in the management of crop protection activities. In order to understand the SWD variability and its influence in winter wheat disease, the objective of this study was to (i) determine th...

Mycosphaerella graminicola strains were isolated from symptomatic winter wheat (Triticum aestivum) and spelt (Triticum spelta) leaves sampled across the Grand-Duchy of Luxembourg. In total, 484 strains were isolated from winter wheat, and 31 from spelt leaves. The sensitivity profiles of these strains towards azoxystrobin (Amistar®, Syngenta Agro G...

A mechanistic model, PROCULTURE, was used over the 2003–2009 period to simulate septoria wheat leaf blotch progression in the canopy in fourreplicated field experiments located in three villages (Diekirch district: Reuler; Grevenmacher district: Burmerange and Christnach), representative of the different agroclimatological zones of the Grand-Duchy...

A stochastic model was developed to predict the wheat leaf rust (Puccinia triticina Eriks.) severity (percentage of leaf area with symptoms showing uredinia) in four-replicated field experiments located in three villages (Diekirch district: Reuler; Grevenmacher district: Burmerange and Christnach), representative of the different agroclimatological...