Search results for "Agricultural Science"

How to develop strategies of adaptation to climate change based on a foresight exercise?

2019

Context and purpose of the study ‐ Prospective studies raise a real intellectual interest for those who contribute to them or take cognizance of it. But they are often considered too difficult to operationalize, and most of the prospective exercises are not followed by action plans, particularly at value chain level. To overcome this difficulty in linking the work of experts and the decisions of stakeholder of value chains, a particular effort was made to operationalize the outcomes from a prospective study on the French vine and wine industry in the context of climate change. The approach consisted in collecting and using the feed‐back of professionalsfrom the wine industry about these out…

Ģeogrāfija. Ģeoloģija. Vides zinātne: referātu tēzes

2008

Intérêts du phénotypage de la personnalité pour améliorer la lutte biologique : cas d’étude chez l’auxiliaire Trichogramma evanescens

2021

One promising approach to improve the use of biological control agents (BCA) consists in the exploitation of intraspecific variation on traits related to mass-rearing or field performance. Consistent inter-individual variations in behaviour (known as personality) have never been considered in biological control (BC) while they have proved to be heritable and correlated to phenotypic traits possibly related to fitness in rearing or field conditions. The aim of this PhD thesis was (i) to develop an experimental design to measure personality traits in a the egg-parasitoid Trichogramma evanescens, and (ii) to evaluate the feasibility and interest of phenotyping personality traits to set and imp…

Survival of two strains of Phthorimaea operculella (Lepidoptera: Gelechiidae) reared on transgenic potatoes expressing a Bacillus thuringiensis cryst…

1998

[Otros] Survie de deux souches de Phthorimaea operculella (Lepidoptera : Gelechiidae) élevées sur des pommes de terre transgéniques exprimant la protéine CrylAb de Bacillus thuringiensis. Deux populations de Phthorimaea operculella (Zeller), l'une supposée résistante au DipelTM (une préparation commerciale de delta-endotoxines de Bacillus thuringiensis) et l'autre sensible, ont été cultivées sur quatre cultivars de pomme de terre, deux transgéniques de première génération, exprimant la protéine CrylAb de Bacillus thuringiensis, et deux non transformés. La population de papillons considérée comme résistante a présenté une mortalité inférieure à celle de l'autre population, mais n'était pas v…

Gas chromatography-mass spectrometry study of polycyclic aromatic hydrocarbons in grass and milk from urban and rural farms

2000

Polycyclic aromatic hydrocarbon (PAH) levels were studied in grass and milk sampled at two farms, one located in a non-contaminated, rural area, and another located in a urban area close to PAH sources such as highways, busy roads, fuel-powered trains and a steel plant. PAH concentration were measured by gas chromatography coupled to mass spectrometry (GC-MS) using internal deuterated standards. In grasses, unexpectedly, although the sum of PAH concentrations was only slightly higher at the urban farm (83.1 ± 16.1 ng g−1) than the rural farm (51.8 ± 10.6 ng g−1), this difference was not observed for all PAH members. This absence of a striking difference of PAH levels between urban and rura…

13C/12C composition, a novel parameter to study the downward migration of paper sludge in soils

2002

δ13C values of crop and forest soils were measured 8 years after disposal of paper sewage sludge. The carbon transfer from paper sludge downward to the first humic layer is evidenced by a 13C-enrichnient of up to + 5.6‰ due to the input of 13C-enriched sludge carbonates. 13C/12C composition is thus a novel, sensitive parameter to follow the downward transfer of paper sludge carbon.

Mécanismes de résistance à l'apoptose induite par TRAIL dans les cellules cancéreuses : restauration de la sensibiltié à TRAIL par la chimiothérapie …

2010

The TNF-family member TRAIL (TNF-related apoptosis inducing ligand) is a cytokine involved in immune anti-tumour surveillance. TRAIL is one of the most promising agents currently under investigation, as it exhibits efficient anti-cancer cytotoxicity with limited side effects on healthy cells. The problem in current cancer therapy is that some cancer cells are already resistant, or can become resistant to TRAIL-induced cell death. The aim of my thesis was to study the mechanisms of resistance to TRAIL, and to find a way to bypass it. First, we were interested in the TRAIL-R4 antagonistic receptor, which is known to bind TRAIL without inducing a death signal. We have demonstrated for the firs…

Characterization of trophic links in an agrosystem : weed seed predation by carabid beetles

2012

Agroecology gives evidence of new perspectives in agriculture, and open doors for alternative weed management approaches through different regulation mechanisms. Seed predation is one of them, and the interest is growing to deepen knowledge, relative to this process. This Phd work aims (i) to describe weed seed predation, the dominant carabid predators and the available resource at a local scale in a common crop (winter wheat); (ii) to study predation profiles of main predators, and the pair-wise correlations between the biological components of the system; (iii) to bring new insights regarding potential regulation of weed communities, through seed predation by carabid beetles. Complementar…

Soil Science Challenges in a New Era: A Transdisciplinary Overview of Relevant Topics

2020

Transdisciplinary approaches that provide holistic views are essential to properly understand soil processes and the importance of soil to society and will be crucial in the future to integrate distinct disciplines into soil studies. A myriad of challenges faces soil science at the beginning of the 2020s. The main aim of this overview is to assess past achievements and current challenges regarding soil threats such as ero-sion and soil contamination related to different United Nations sustainable development goals (SDGs) including (1) sustainable food production, (2) ensure healthy lives and reduce environmental risks (SDG3), (3) ensure water availability (SDG6), and (4) enhanced soil carbo…

Analysing farming systems with Data Envelopment Analysis: citrus farming in Spain

2004

Abstract Farming systems in the Mediterranean agricultural areas of Spain are frequently characterised by the small size of the production units and a widespread strategy of externalisation of many growing tasks which could be seen as a way of allowing farms to remain competitive. In this paper, we suggest Data Envelopment Analysis as an appropriate analytical tool to explore the possibilities of short-term viability of individual farms, after eliminating current inefficient practices. From a sample of Spanish citrus farms, we identify the efficient production units that determine the technological or best practice frontier, and we compare their characteristics with those of the average far…