2. Variétés - 2. Escourgeon et orge d'hiver fourragers

in Destain, Jean-Pierre; Bodson, Bernard (Eds.) Livre Blanc - Céréales - Gembloux (2012, September 06)

Assessing the potential of an algorithm based on mean climatic data to predict wheat yield.

Conference (2012, July)

Real-time non-invasive determination of crop biomass and yield prediction are maybe among the major challenges in agriculture. But unknown future weather remains the key point of accurate yield forecast ... [more ▼]

Real-time non-invasive determination of crop biomass and yield prediction are maybe among the major challenges in agriculture. But unknown future weather remains the key point of accurate yield forecast. This paper presents the results of a preliminary study that aims to supply the unknown future by daily mean climatic data. The results show that under the Belgian weather, this approach is relevant. Furthermore, the developed methodology appears to be a powerful diagnosis tool of the remaining yield potential under ongoing weather. [less ▲]

Dynamique de dégradation des résidus de culture dans le sol en fonction de la profondeur d'enfouissement et de la quantité enfouie. Impacts sur le développement des cultures en place

Poster (2012, March)

10. Perspectives - Dynamique des populations de trois adventices des céréales en vue de la mise au point de méthodes intégrées de leur contrôle

in Livre Blanc - Céréales - Gembloux (2012, February 29)

4. La fumure azotée

in Livre Blanc - Céréales - Gembloux (2012, February 29)

Impact of cultivation practices on soil respiration

Poster (2012, February 08)

In addition to its, evident, food supply function, agriculture is subjected to various pressures and has to respond to many challenges like reducing its CO2 emissions, maintaining or improving the soil ... [more ▼]

In addition to its, evident, food supply function, agriculture is subjected to various pressures and has to respond to many challenges like reducing its CO2 emissions, maintaining or improving the soil quality, maintaining productivity, sequestrating of the carbon stock in soil... Cultivation practices are known to induce a modification of soil organic matter quantity, quality and spatial distribution, which may impact dry matter decomposition kinetics. In order to bring answers to these questions, a multidisciplinary project (SOLRESIDUS) was set up by the University of Liege, Gembloux Agro-Bio Tech in collaboration with Walloon Agricultural Research Centre (CRA-W). The aim was to investigate the impact of cultivation practices (tillage and residue restitution) on crop growth, yield and environment, as well as on soil properties and on activities. In the present study, we focused on the impacts on soil CO2 fluxes. The experimental site is situated in Gembloux, in the Belgian loamy region. The plot is divided into 4 latin squares where two tillage modalities (plough after 2 stubble breaking vs only 2 stubble breaking) and two straw management practices (restitution vs. exportation) were compared. For 3 years, soil respiration was measured with automatic and manual dynamic soil chambers. Moreover, soil respiration was measured as well in cropping zone (total respiration) as in root exclusion zones created with root exclusion cylinders (heterotrophic respiration). As first results, we observed: -a significantly higher flux in plots with residue restitution, which is clearly explained by the larger amount of organic carbon prone to decomposition; -a decrease of standardized heterotrophic respiration (linked with residue decomposition) during growing seasons; -no significant differences in soil respiration between tillage modalities after 3 growing seasons. The experiment is still in progress, more years being necessary in order to evaluate the long-term impacts of cultivation practices on soil respiration. [less ▲]

Simulation de la croissance du blé à l’aide de modèles écophysiologiques : Synthèse bibliographique des méthodes, potentialités et limitations.

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2012), 16(3), 376-386

Crop models describe the growth and development of a crop interacting with its surrounding agro-environmental conditions (soil, climate and close conditions of the plant). However, the implementation of ... [more ▼]

Crop models describe the growth and development of a crop interacting with its surrounding agro-environmental conditions (soil, climate and close conditions of the plant). However, the implementation of such models remains difficult because of the high number of explanatory variables and parameters. It often happens that important discrepancies appear between measured and simulated values. This article aims to highlight the different sources of uncertainty related to the use of crop models, as well as the actual methods that allow to compensate or, at least, to consider these sources of error during the model result analysis. This article presents a literature review that firstly synthetises the general mathematical structure of crop models. The main criteria for evaluating crop models are then described. Finally, several methods used for improving models are given. Parameter estimation methods, including frequentist and Bayesian approaches, are presented and data assimilation methods are reviewed. [less ▲]

A method for plant leaf area measurement by using stereo vision

in A préciser (2012)

This paper presents a method for the measurement of LAI of wheat in situ. By using stereoscopic images a 3D map was computed. One colour image was segmented to identify plant regions and the 3D leaf area ... [more ▼]

This paper presents a method for the measurement of LAI of wheat in situ. By using stereoscopic images a 3D map was computed. One colour image was segmented to identify plant regions and the 3D leaf area was computed on these regions. The result showed that the precision was about the same as for the reference measurements but required a lesser workload. [less ▲]

4. Froment 2011: une récolte disparate

in Livre Blanc: Céréales-Gembloux - Informations avant les semis (2011, September 08)

1. Implantation des cultures

in Livre Blanc - Céréales-Gembloux - Informations avant les semis (2011, September 08)