Search results for "Sciences agricoles"
showing 10 items of 16 documents
Genomic variation in tomato, from wild ancestors to contemporary breeding accessions
2015
[EN] Background: Domestication modifies the genomic variation of species. Quantifying this variation provides insights into the domestication process, facilitates the management of resources used by breeders and germplasm centers, and enables the design of experiments to associate traits with genes. We described and analyzed the genetic diversity of 1,008 tomato accessions including Solanum lycopersicum var. lycopersicum (SLL), S. lycopersicum var. cerasiforme (SLC), and S. pimpinellifolium (SP) that were genotyped using 7,720 SNPs. Additionally, we explored the allelic frequency of six loci affecting fruit weight and shape to infer patterns of selection. Results: Our results revealed a pat…
The Agr communication system provides a benefit to the populations of Listeria monocytogenes in soil
2014
International audience; In this study, we investigated whether the Agr communication system of the pathogenic bacterium Listeria monocytogenes was involved in adaptation and competitiveness in soil. Alteration of the ability to communicate, either by deletion of the gene coding the response regulator AgrA (response-negative mutant) or the signal pro-peptide AgrD (signal-negative mutant), did not affect population dynamics in soil that had been sterilized but survival was altered in biotic soil suggesting that the Agr system of L. monocytogenes was involved to face the complex soil biotic environment. This was confirmed by a set of co-incubation experiments. The fitness of the response-negat…
Agroecological engineering
2015
Earth has recently entered the new era of the Anthropocene, during which the rise of human activities are impacting for the first time ecosystems and climate on the global scale. Since the 1960s the green revolution has improved food production in quantity using industrially-designed agriculture, which has led to global pollution by pesticides and losses of food quality, biodiversity and soil carbon. As a consequence there is a need to implement agroecological practices in order to produce food safely and in a sustainable way. This virtual issue presents principles and applications of agroecological engineering, exemplified in 19 selected review articles from the journal Agronomy for Sustai…
Projet BILAG : une bibliométrie de la littérature scientifique mondiale sur les légumineuses à graines pour comprendre la dynamique de la recherche s…
2018
Quel poids ont les différentes disciplines scientifiques dans la recherche mondiale sur les légumineuses à graines ? Quelles sont les espèces les plus étudiées et sur quels sujets ? Comment évoluent les champs de connaissance de la recherche sur les légumineuses à graines ? Quels champs de connaissances émergent et se restructurent ? Quelle est la place des différents instituts de recherche dans ce maillage, et tout particulièrement ceux des pays francophones ? Pour répondre à ces questions, un groupe d'experts interdisciplinaires sur les légumineuses et d'ingénieurs de l'information scientifique, a moissonné/collecté un corpus d'articles scientifiques sur les légumineuses à graines (telles…
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
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…
Indicators of agricultural intensity and intensification: a review of the literature
2015
Since the 1960s, research has dealt with agricultural intensification (AI) as a solution to ensure global food security. Recently, sustainable intensification (SI) has increasingly been used to describe those agricultural and farming systems that ensure adequate ecosystem service provision. Studies differ in terms of the application scales and methodologies, thus we aim to summarize the main findings from the literature on how AI and SI are assessed, from the farm to global levels. Our literature review is based on 7865 papers selected from the Web of Science database and analysed using CorText software. A further selection of 105 relevant papers was used for an in-depth full-text analysis …
Microbial diversity and structure are drivers of the biological barrier effect against Listeria monocytogenes in soil
2013
International audience; Understanding the ecology of pathogenic organisms is important in order to monitor their transmission in the environment and the related health hazards. We investigated the relationship between soil microbial diversity and the barrier effect against Listeria monocytogenes invasion. By using a dilution-to-extinction approach, we analysed the consequence of eroding microbial diversity on L. monocytogenes population dynamics under standardised conditions of abiotic parameters and microbial abundance in soil microcosms. We demonstrated that highly diverse soil microbial communities act as a biological barrier against L. monocytogenes invasion and that phylogenetic compos…
Microalgae community structure analysis based on 18S rDNA amplification from DNA extracted directly from soil as a potential soil bioindicator
2005
International audience; Soil algae are photosynthetically active microorganisms showing changeable community structure, depending on the soil type, the agricultural practices and the application of pesticides. To characterise algal community structure, molecular approaches complementary to classical microbiological approaches based on the isolation and the culture of soil algae are required. Our study describes a polymerase chain reaction (PCR) approach targeting algal 18S rDNA sequences of desoxyribonucleic acid (DNA) samples extracted either from unialgal eukaryotic microalgae culture, complex assemblages of microalgae populations or natural soil communities. Our first results showed that…
Enhanced isoproturon mineralisation in a clay silt loam agricultural soil
2005
International audience; 14C-ring-labelled isoproturon mineralisation was investigated in a French agricultural soil previously exposed to isoproturon. 50 different soil samples collected every 2 m along a transect of 100 m in length were treated one or two times with isoproturon under laboratory conditions and analysed by radiorespirometry. 94% of the soil samples showed a high ability to mineralise isoproturon with a relatively low variability in the cumulative percentage of mineralisation ranging from 30 to 51% of the initially added radioactivity for the samples treated once with the herbicide. About 45 to 67% of the initially added radioactivity was transformed into 14CO2 in soil sample…