Search results for "EED"
showing 10 items of 5952 documents
What are the biological determinants of regeneration of perennial weeds? Effect of fragment weight and bud number on the regrowth of five perennial w…
2022
Perennial weeds have become an increasing problem with the reduction of herbicide use andtillage. Because of their capacity to regenerate from vegetative organs, such as roots andrhizomes, they must be controlled with different management techniques than annuals. Todate, few studies exist on this topic and farmers often lack solutions to control perennials intheir cropping systems. Management strategies must focus on the depletion of theregenerative organ reserves to hamper the production of new shoots. However, there is aneed for a better understanding of below-ground organs physiology and the determiningfactors of their regrowth capacities.Our aim was to assess the number of shoots and th…
Modélisation des effets des systèmes de culture sur la dynamique de l’orobanche rameuse en interaction avec les adventices
2016
Branched broomrape, Phelipanche ramosa (L.) Pomel, is a parasitic plant which causes important yield losses in crops, particularly in winter oilseed rape in France. In order to design efficient pest management strategies, we modelled the effects of cropping systems on branched broomrape dynamics in interaction with weeds and crops in a model called PHERASYS. PHERASYS functions and parameters were based on literature and on our own experiments. The model simulates the complete life-cycle of the parasite, from seed dynamics in the soil to seed production after development on the host. Interactions between the parasite and crops and weeds were characterized at the species level and at the plan…
Parameterizing the "grassland" module in the multispecific model FlorSys
2013
EAEcolDurCT1; The multispecies model FlorSys can predict the effects of cropping systems on the dynamics of weed communities in annual crops ; however, it is not configured to predict the fate of weeds in permanent cover such as grasslands. We realized the simulation of a weed seed rain in controlled conditions to estimate the percentage of weed seeds intercepted by a grass cover. Parameters of this linear model will be used to develop a new sub model in FlorSys to be able to simulate weed dynamics in temporary grasslands. We used twelve weed species selected on the basis of specific morphological characteristics and observations made in the experimental set up of SOERE ACBB (Observatory En…
Les coléoptères carabiques sont-ils plus sélectifs face à un risque de prédation ou de compétition ?
2017
Le temps nécessaire à l’évaluation et à l’acceptation d’une ressource est directement lié à sa qualité. Ainsi, les individus s’approvisionnant dans un milieu naturel font face à un compromis entre vitesse de prise de décision et qualité de la ressource (speed-accuracy trade-off). Si la qualité de la ressource est un élément important pour favoriser sa valeur adaptative (fitness), le temps nécessaire au processus de décision n’est plus disponible pour d’autres tâches essentielles comme la vigilance. De plus, une prise de décision trop longue expose aussi les individus à un risque plus important de compétition et de perte d’opportunités. On s’attend à ce que des animaux confrontés à un risque…
I-Weed robot : un outil pour l'étude de population de plantes adventices
2016
The I-Weed robot is a small autonomous platform that aims to characterize the vegetation in an inter-row maize crop for a spot spraying: spraying is done only where a weed is detected. This article presents how the robot works and aims to experimentally evaluate the ability to map weeds from a WeedSeeker system (Trimble) embedded on the I-Weed robot. The results are compared to those from an imaging system, used as ground truth. After analyzing a confusion matrix, it reveals that the system is able to correctly geotag plants at 75 % and is ready for a spot spraying.
Role of vacuolar sulfate in nutritional quality of pea seeds
2022
Grain legumes have a key role to play in both agroecological and food transitions. Indeed, these plants are able to accumulate large amounts of proteins in their seeds even in the absence of nitrogen fertilization thanks to symbiotic N2 fixation in the root nodules. However, legumes are exposed to abiotic stresses, including nutrient deficiencies, making it important to optimize nutrient use efficiency for maintaining seed protein content and quality. Seed protein quality refers to the ability of the seed proteins to meet the body’s requirements for essential amino acids. It strongly depends on the amino acid balance, which determines protein digestibility. In pea (Pisum sativum) seeds, met…
Role of vacuolar sulfate in the nutritional quality of pea seeds
2022
Legumes have a key role to play in both agroecological and food transitions due to their ability to accumulate large amountsof seed proteins without nitrogen fertilization thanks to symbiotic N2 fixation in the root nodules. However, in agroecologicalsystems, legumes are more exposed to nutrient deficiencies, including sulfur deficiency, than in conventional systems, makingit important to optimize nutrient use efficiency for maintain seed protein quality, in particular the level of (semi) essentialamino acids like methionine and cysteine. These sulfur-containing amino acids are synthetized through the sulfur metabolicpathway starting from sulfate reduction. Sulfate is taken up from the soil…
Quantification of the contribution of weed seed predators to crop yield
2023
30 book of abstracts; International audience
Robotics for weed control: I-Weed Robot for a specific spraying
2012
International audience; To preserve environment for a sustainable agriculture, we explore the development of a new autonomous robot, called I-Weed Robot (Intelligent Weed Robot), which aims at reducing herbicides in crop fields (maize, sunflower...). Using a high precision positioning signal (RTK) to locate the robot in the field, a Kaman filter and a proportional-integral-derivative controller (PID controller) allow adjusting the orientation of the robot depending on a predefined trajectory. As for the spraying system, a camera in front of the mobile platform detects weed plants thanks to an image processing based on a crop/weed discrimination algorithm (Hough Transform). At the back a spr…
New Decision-making Tools for sustainable Weed Control
2021
En 2017, le Conseil fédéral suisse a adopté le pland’action visant à la réduction des risques et à l’utilisation durable des produits phytosanitaires. L’une desmesures de ce plan est «la renonciation complète oupartielle aux herbicides». Or, celle-ci n’est réalisablequ’au travers d’une stratégie de gestion globale desadventices, à l’échelle de la culture et de la rotation. Eneffet, les adventices sont nuisibles pour la culture enplace l’année en cours, mais aussi de manière pluriannuelle par le biais de leur stock semencier. La mise enœuvre de mesures préventives et curatives basées surles principes de la protection intégrée nécessite denouveaux outils d’aide à la décision. Des indicateursd…