Search results for "growth"
showing 10 items of 5134 documents
Involvement of communication systems during the sessile growth of Listeria monocytogenes
2007
International audience
Digital tools for a biomass prediction from a plant-growth model. Application to a weed control in wheat crop
2019
International audience; Weed control is essential for crop quality and yield. Usually, the main factors affectingdecision-making of farmers in weeding are based on the presence of certain weedvarieties and their density (plants/m2). However, the weed management at the scale ofthe crop cycle refers to other competition indicators, more reliable, such as plantbiomass or leaf area index (LAI). Classically, plant biomass measurements are obtainedby a destructive method of sampling, time consuming and it turns out to be unworkablein practice for farmers. This project proposes to study an innovative method of biomassevaluation which is based on the acquisition of plot images to determine the leaf…
Growth and development of Ambrosia artemisiifolia L. under different trophic conditions
2014
Ambrosia artemisiifolia L. (common ragweed) is an annual weed regarded as an invasive plant in France. This species can be found in a large range of soil types with regard to texture, pH or nutrient contents. Furthermore, its tolerance to different forms of stress increases its spread potential. This work was undertaken to evaluate the development and growth of common ragweed under different trophic conditions in a common garden. Three cohorts of 15 plants per treatments were sown in spring 2013 and the effects of nitrogen and irrigation were compared on each sowing dates. During the first weeks, vegetative appearance is strongly linked with the sum of temperature. For the first cohort, the…
Characterization of the role of flagellin in the innate immunity triggered by the endophytic pgpr burkholderia phytofirmans in arabidopsis and grapev…
2014
International audience
Impact of the growth of different maize genotypes on arbuscular mycorrhizal fungi
2001
International audience
Services provided by soil microorganisms to improve plant phosphate nutrition
2022
Since the first Green Revolution, agricultural practices have been based on the massive use of synthetic fertilisers and plant protection products. Since then, global consumption of phosphate fertilisers has more than tripled, reaching 47 million tonnes in 2019. Current projections estimate that phosphate rock stocks (natural phosphorus resources for fertiliser production) could be depleted within the next century, leading us to change our agricultural practices. In soils, P is mainly present in complexed forms that are not easily accessible to plants. To reduce the use of phosphate fertilisers, it is necessary to make this complexed phosphate accessible to plants. This can be done by benef…
Spatial distribution of ammonia-oxidizing bacteria and archaea across a 44-hectare farm related to ecosystem functioning
2011
Characterization of spatial patterns of functional microbial communities could facilitate the understanding of the relationships between the ecology of microbial communities, the biogeochemical processes they perform and the corresponding ecosystem functions. Because of the important role the ammonia-oxidizing bacteria (AOB) and archaea (AOA) have in nitrogen cycling and nitrate leaching, we explored the spatial distribution of their activity, abundance and community composition across a 44-ha large farm divided into an organic and an integrated farming system. The spatial patterns were mapped by geostatistical modeling and correlations to soil properties and ecosystem functioning in terms …
Economies d'agglomération et configurations spatiales dans les espaces ruraux
1997
The question to be addressed here is that of the agglomeration/dispersion forces that are likely to account for the location of people and jobs in rural areas and the way they explain spatial patterns in rural areas depending on urban influence. Economic geography models may provide suitable tools with which to investigate the organization of rural areas. We first review these models, focusing on dispersion forces, which rest basically on land consumption and transport costs. We suggest then a set of hypotheses concerning the main forces at work in rural areas. Intensity of agglomeration economies is hypothesized to be related to the urban size, which in turn induces increasing land rents a…
Dendro-archaeological contribution to the history of forest exploitation. The case of the Gallo-Roman settlement of Odenburg (Alsace, France) between…
2010
L'immigration dans quelques communes de la banlieue ouest : Asnières, Nanterre et Puteaux de 1830 à 1930
1990
A study of immigration for the period 1 830-1 930 for three communes in the western suburbs of Paris has been undertaken with the aid of official marriage certificates. The study tends to show that each suburban commune's immigrants, coming primarily from the provinces and secondarily from Paris, have been chosen to some extent since they reflect the economic activities and the social composition of the population of the commune of arrival. This selection occuring within national migration streams seems to favour the migrants insertion, at least until the beginning of the twentieth century.