Search results for "Agricultural Science"
showing 10 items of 901 documents
Consequences of sown grass margin strip on weed flora
2010
The intensification of the management of weed populations, led by a potential decrease in the yield and quality of crop harvest, has largely induced their decline in arable zones across the last decades. This floristic decline in arable landscape, has induced a loss of a larger biodiversity because the presence of others organisms (birds, insects, mammals) are strongly linked with the abundance of trophic resources as weed are. To counter with this loss of biodiversity and to limit the negative impacts of farming practices on environment, numerous agri environmental schemes were launched through Europe. In France, sown grass strips were established by farmers along streams and rivers to lim…
Prévalence de pathogènes humains dans les sols français, effet des facteurs pédoclimatiques, biologiques et du mode d'utilisation des sols
2013
Soil contamination by bacterial pathogens can occur through manure, sewage sludge spreading or irrigation using waste water treatment plants effluents. Agricultural soils may act as reservoirs for these pathogens, play a significant role in their dissemination, leading to the potential contamination of food and water resources. Health risk associated with the occurrence of pathogens in environmental matrices has to be thoroughly evaluated. In this context, the objectives of this work were: i) to determine the prevalence of two pathogenic bacterial species (Listeria monocytogenes and Enterococcus faecalis) in a large collection of French soils originated from a systematic soil survey of the …
Dynamique et assemblage des communautés adventices : Approche par modélisation statistique
2011
To develop solutions for a productive and sustainable agriculture, principles, theories, andmethods of ecology may contribute to understand the biological processes governing the agroecosystem.The present case study was based on data collected by a network of observatories of weeds covering the whole of France (‘Biovigilance Flore’) and aimed at establishing forrules governing the assemblage and dynamics of weed communities in fields grown with annual crops. We particularly studied the possible relationships between species within acommunity, as well as the relationships between communities and their environment. Analyses were based on species abundances to take account of their effect on c…
Spray droplet characteristics measured using high speed imaging techniques
2016
Presented at Conference International Advances in Pesticide Application (IAPA), Barcelone, ESP (2016-01-13 - 2016-01-15).; International audience; Spray droplet characteristics are important features of an agricultural spray. The objective of this study is to measure the droplet size for different types of hydraulic spray nozzles using a developed backlighted image acquisition system and image processing technique. An in-focus droplet criterion was established to decide whether a droplet is in focus and can be measured in an accurate way. Tests included five different nozzles (Albuz ATR orange and red, TeeJet XR 110 01, XR 110 04 and Al 110 04).
Raisonnement des pratiques et des changements de pratiques en matière de désherbage : regards agronomique et sociologique à partir d’enquêtes chez de…
2008
To ensure successful, more sustainable weed management practices, it is crucial to take account of farmer’s decision-making processes. Agronomists revealed that interviewed farmers had complex and various weeding programmes, and that, when designing these programmes, they integrated different time scales: the current year, the rotation, and the long term. They gave some light, too, on the decision-making processes and how it changes over time. Sociologists analyzed the way wine-growers bring about change from the cognitive angle and its bearing on interactive dialogue between the wine-growers themselves as well as with technical advisors
Caractérisation des communautés microbiennes dans les technosols construits pour la restauration des friches industrielles
2012
Increasing soil degradation and its consequences on overall ecosystem services urge for restoration strategies. Construction of Technosols through assemblage of treated soil and industrial wastes is an innovative technology for the restoration of polluted land and re-use of industrial by-products. Recent studies have evidenced that Technosols could support ecosystemic services such as primary production but the knowledge about other soil functions, such as biogeochemical cycling, is limited. Due to the significant contribution of microbial communities to soil functioning, this PhD work was carried out to study the effect of the type of Technosol on microbial communities with a focus on func…
Les effets conjugués de la gestion parcellaire et du contexte paysager et de sa dynamique sur les bioagresseurs et les niveaux de régulation biologiq…
2017
International audience; De nombreux travaux ont mis en évidence que les caractéristiques du paysage environnant les parcelles agricoles influencent les abondances d’ennemis naturels et le niveau de régulation biologiquedans les cultures. Les effets du paysage sur l’abondance de bio-agresseurs sont par contre encore peu étudiés. Les effets du paysage sur la régulation biologique sont parfois contradictoires, souventspécifiques aux sites et de ce fait encore peu généralisables. Des travaux récents suggèrent que ces variations de réponse peuvent résulter d’interactions entre gestion parcellaire et contexte paysager,avec des effets conditionnels du paysage selon le type de gestion parcellaire e…
Review of factors influencing the success or failure of biocontrol: technical, industrial and socio-economic perspectives
2010
Communication orale au 11. IOBC-WPRS Meeting of the working group "Biological control of fungal and bacterial plant pathogens". Climate change: challenge or threat to biocontrol?, 2010/06/07-11 ; Graz (AUT).; International audience; Although their role in plant health management is still quite modest, ever increasing expectations are placed on biocontrol agents for the complementation or replacement of pesticide use. Despite decades of research and more than 12,000 scientific papers on biological control of plant diseases, little more than 14 microbe-based commercial products are presently registered for use against diseases in the European Union. Through a review of published scientific li…
Des agronomes pour demain : Accompagner la diversité des agricultures pour un développement durable
2008
International audience; Cet ouvrage constitue la synthèse des IVe Entretiens du Pradel, qui se sont tenus en 2006, sur le thème « Agronomes et diversités des agricultures ». Étudier, comparer les différents types d'agriculture en vue de l'action représentent une activité de l'agronome moderne. Ce dernier est confronté à de nouveaux enjeux qu’il doit bien mesurer, et à des défis qu’il aura à relever, pour que l’agriculture du XXIe siècle puisse à la fois nourrir l’humanité et offrir un cadre de vie non dégradé. Ce livre met en avant la nécessité d’une nouvelle politique pour les agronomes, et, par conséquent, d’une nouvelle dynamique de recherche, de formation et de développement. Il intéres…
Historique des herbicides en France depuis la seconde guerre mondiale
2012
National audience; Au lendemain de la seconde guerre mondiale, les herbicides ont joué un rôle important dans la réponse du monde agricole aux besoins alimentaires des populations, notamment grâce aux économies de main-d’œuvre et aux facilités de gestion qu’elles ont permises. Pourtant, aujourd’hui, l’agriculture intensive et productiviste fait l’objet d’une remise en cause du fait de son impact sur l’environnement, en particulier sur les ressources en eau (présence de nitrates, substances actives (SA) phytosanitaires). Face à la réglementation européenne et pour répondre aux préoccupations de l’opinion publique, mais aussi du monde agricole, il a été mis en place en France le Plan Ecophyto…