eKhSACIR інституційному репозитарії Харківської державної академії культури
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Using crop-pathogen modeling to identify plant traits to control Zymoseptoria tritici epidemics on wheat
No full textDiversification in pathogen control methods to reduce the severity of economically important foliar diseases such as Zymoseptoria tritici on wheat is needed. One way is to identify plant physiological and architectural traits that influence disease development and that can be selected in the process of crop breeding. Such traits may be used for improving tolerance or disease escape. Traits favoring disease escape, the focus of our work, may significantly decrease crop epidemics (Robert et al., 2018). However, understanding the role of such traits in crop-pathogen interactions is a daunting task because the interactions are multiple and dynamic in time. To characterize and quantify crop-pathogen interactions, an innovative trait-based and resource-based modeling framework was developed (Precigout et al., 2017). In this framework, the pathosystem is assumed to respond dynamically to both architecture and physiological status of the host canopy. A canopy consists of plenty of small patches, i.e. small functional and infectable units of leaf tissue. Production of new patches, for canopy growth and renewal of photosynthetically active plant tissues, is a function of the available resources produced by the other patches. Pathogen spores can contaminate nearby healthy patches. The definition of patch proximity depends on dispersal abilities of the pathogen and canopy architecture. We used and adapted this modeling framework to quantify the effects of several plant traits on Zymoseptoria tritici epidemics for varied climate scenarios. The complex infection cycle of Z. tritici characterized by a long symptomless incubation period was implemented in the model. We studied plant architectural traits such as leaf size or stem height, and plant physiological traits such as leaf lifespan or leaf metabolite contents. In our simulations, these traits impacted the epidemics dynamics though their effects on pathogen dispersal and on the amount of resources available for the pathogen. Sensitivity analyses showed how disease severity depended on plant traits and pathogen virulence. The importance of several plant and pathogen traits could be linked to the pathogen’s ability to manage the race for the colonization of the canopy in the face of canopy growth. Playing on host traits also made it possible to simulate different wheat varieties - with contrasted heights, pathogen resistance or precocity - to characterize the behavior of the pathosystem of interest for different host ideotypes. We argue that this kind of trait-based modeling approach is a valuable tool to identify plant traits promoting more resilient agroecosystems in particular for crop breeding in a context of innovative and sustainable crop protection
ModelEco : MODELisation en programmation mathématique pour l'analyse ECOnomique de l'agriculture
No full textDocument présenté lors de l'atelier collaboratif n° 4 : Innovations pédagogiques en sciences socialesNational audienc
Valorisation des rations à base de foin séché en grange par les chèvres laitières
No full textSession AlimentationNational audienc
Combining simplicity and complexity: creating user-applications from mechanistic nutritional models
No full textInternational audienceMathematical models are useful to represent, understand, and predict the response of animals to the nutrient supply. These models often use a compartmental representation, involving a large number of compartments and parameters. However, few (if any) mechanistic models are capable to fully grasp the temporal and spatial aspects of nutrient metabolism, and much of what we do not understand or fail to quantify ends up as maintenance or inefficiencies. Practical application of a model requires the transformation of the model into a user-friendly tool. Decisions have then to be made as to which parameters will be hard-coded in the tool compared to those that can be modified by the user based on knowledge and observations. Proper parameterization of a model allows identifying parameters that have most impact on outcomes (in an independent way) and facilitates parameter estimation. For example, empirical equations such as the Gompertz or logistic function are often used to represent the potential protein or lipid deposition in growing animals. One of the parameters in these models is the protein or lipid mass at maturity. However, little information is available on the mature protein or lipid mass of animals such as pigs and poultry fed ad libitum throughout their life. Reparameterization of the model (e.g., replacing the mature protein mass by the protein deposition during the productive life of the animal) and the use of proxies (using body weight gain as a proxy for protein deposition) are essential for the practical application of the model. Recent developments in sensor technologies including real-time monitoring will undoubtedly revive the interest in nutritional modeling, especially in the context of precision livestock farming. These developments may involve a shift in paradigm in model development from a “concept-driven approach” towards a more “data-driven approach”, where models have to accommodate observed data
Cinquante années d’amélioration génétique du porc en France : bilan et perspectives
No full textCinquante années d’amélioration génétique du porc en France : bilan et perspectives. 50. Journées de la Recherche Porcine
Exploring non-additive variance using genome-wide dense SNP in four French and Nordic dairy cattle breeds
No full textInternational audienc
Flow cytometry: a relevant tool to assess the integrity, polarization, and fluidity of bacterial cytoplasmic membrane
No full textpas de résum
Using additional single nucleotide polymorphisms selected from whole genome sequence data for genomic prediction in Danish Jersey
No full textInternational audienc
Evolutionary history of tropical tree species complexes: species delimitation and adaptive genetic variation in the Brazil nut clade (Lecythidaceae)
No full textEvolutionary history of tropical tree species complexes: species delimitation and adaptive genetic variation in the Brazil nut clade (Lecythidaceae). European Conference of Tropical Ecology (GTOE2018
Genome-wide study of structural variants in French dairy and beef breeds
No full textInternational audienc