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Due to their deployment flexibility, Unmanned Aerial Vehicles have been found suitable for many application areas, one of them being air pollution monitoring. In fact, deploying a fleet of Unmanned Aerial Vehicles (UAVs) and using them to take environmental samples is an approach that has the potential to become one of the key enabling technologies to enforce pollution control in industrial or rural areas. In this paper, we propose to use an algorithm called Pollution-driven UAV Control (PdUC) that is based on a chemotaxis metaheuristic and a Particle Swarm Optimization (PSO) scheme that only uses local information. Our approach will be used by a monitoring Unmanned Aerial Vehicle to swiftly cover an area and map the distribution of its aerial pollution. We show that, when using PdUC, an implicit priority is applied in the construction of pollution maps, by focusing on areas where the pollutants' concentration is higher. In this way, accurate maps can be constructed in a faster manner when compared to other strategies. We compare PdUC against various standard mobility models through simulation, showing that our protocol achieves better performances, by finding the most polluted areas with more accuracy, within the time bounds defined by the UAV flight time.

Fire blight, caused by Erwinia amylovora, is a major disease of pear (Pyrus communis L.). Different strategies to enhance fire blight resistance of pear through genetic engineering are currently studied in our group. Among them, transformation of pear with a depolymerase gene from a bacteriophage has been investigated. This gene encodes an enzyme that degrades the capsular exopolysaccharide (EPS) of E. amylovora. Mutant strains without bacterial EPS are known to fail to colonize host plants. Pear cv. ‘Passe Crassane’ was transformed with Agrobacterium tumefaciens EHA105pBinAR-dpo carrying the depolymerase gene under the control of the CaMV35S promoter. Sixteen transgenic diploid clones were obtained and analysed by western blot and RT-PCR. In vitro tests for fire blight resistance were performed by inoculation with a virulent strain of E. amylovora. Two transgenic clones showed a slight reduction of fire blight symptoms (about 15 %) in comparison to non-transformed plants. This partial resistance was correlated with a stronger expression of the transgene at transcriptional and traductional levels. Very low depolymerase activity was detected in most transgenic clones (0.006% of total soluble proteins). Greenhouse evaluation of fire blight resistance of the depolymerase clones is under investigation on acclimatized plants.

This paper describes a simple and fast way to predict efficiency of DCT-based filtering of images corrupted by signal dependent noise as this often happens for hyperspectral and radar remote sensing. Such prediction allows deciding in automatic way is it worth applying denoising to a given image under condition that parameters of signal-dependent noise are known a priori or pre-estimated with appropriate accuracy. It is shown that denoising efficiency can be predicted not only in terms of traditional quality criteria as output MSE or PSNR but also, with slightly less accuracy, in terms of visual quality metrics and PSNR-HVS-M.

Two Radiation Belt Activity Indices, based on electron flux measurement >300 keV and >1.6 MeV, and one Solar Proton Event Alarm, based on proton flux measurement >75 MeV, are developed for post events analysis. Both indices and alarm are plotted over the last 30 days on the CRATERRE project web site and are daily updated.

International audience; An adaptive, hyperspectral imager is presented. We propose a system with easily adaptable spectral resolution, adjustable acquisition time, and high spatial resolution which is independent of spectral resolution. The system yields the possibility to define a variety of acquisition schemes, and in particular near snapshot acquisitions that may be used to measure the spectral content of given or automatically detected regions of interest. The proposed system is modelled and simulated, and tests on a first prototype validate the approach to achieve near snapshot spectral acquisitions without resorting to any computa-tionally heavy post-processing, nor cumbersome calibration.

Deux champignons endomycorhizogènes à arbuscules (Glomus intraradices, Glomus caledonium), introduits pendant la période d’acclimatation, ont été testés pour leur pouvoir infectieux et leur effet sur la croissance de plants micropropagés de merisiers (Prunus avium L) transplantés dans deux différents sols neutres, préalablement désinfectés ou non. Les vitroplants endomycorhizés présentent une meilleure croissance que les plantes témoins sur les deux sols désinfectés. L’importance de l’augmentation de croissance est corrélée à une importante infection mycorhizienne. Cependant, la nature du sol influence l’établissement de la symbiose et son effet sur la croissance des plantes. Sur sols non désinfectés, une mycorhization préalable des plants micropropagés de P avium est bénéfique en utilisant des champignons endomycorhizogènes sélectionnés pour leur efficacité dans ces sols. La réponse à l’infection endomycorhizienne est également fonction du clone de plants micropropagés de merisiers. Une seconde étude a également montré que l’endomycorhization du merisier a un effet bioprotecteur vis-à-vis du champignon pathogène Phytophthora cinnamomi. Two species of arbuscular mycorrhizal (AM) fungi (Glomus intraradices, Glomus caledonium) introduced during post vitro acclimatization were tested for infection development and growth effects in Prunus avium, after transplantation into two types of disinfected or undisinfected neutral soils. Endomycorrhizal plants grew better than nonmycorrhizal plants in both disinfected soils. Growth improvements by either fungus were related to a high level of mycorrhizal colonization. Mycorrhizal effects on P avium plants and mycorrhiza development depended on the soil type. In undisinfected soils containing an infective but inefficient AM fungal population, growth of Prunus was improved by preinoculation with effective AM fungi adapted to the soil type. Moreover, clonal variations in AM development and mycorrhizal responsiveness to Glomus mosseae were observed in three P avium clones. The bioprotective effect of AM was shown in one clone where the presence of G mosseae eliminated the negative impact of Phytophthora cinnamomi on root growth.

All organic agricultural systems suffer from a lack of plant cultivars adapted to organic production. Within the framework of the European project SOLIBAM (Strategies for Organic and Low Input Breeding and Management) a study was undertaken to determine which cultivars farmers grow, why they grow them, and the expectations in plant breeding of organic stakeholders. A comprehensive range of investigations carried out between 2010 and 2012 provided information on the state of organic seed in France. Results fit with the hypothesis that the market is a significant factor influencing the choice of seeds and cultivars (local cultivars, landraces, modern cultivars). Expectations and practices of producers selling on a local market (i.e., direct sale) differ radically from those of producers selling to long food supply chains. This study shows that the availability and use of organic seeds have significantly improved over the last three years. A vast majority of organic producers willingly use organic seeds, with, on average, 45-70% (cereals) and 75%-100% (vegetables) of organic seeds being planted on farms. However, the total number of derogations remains quite high: there is still space for improvement in organic seed use and supply in France. Several limiting factors and levers were identified during the study, as well as farmers' expectations for the future on horticultural crops. The case study on tomatoes states the differences between producers selling on a local market and those of producers selling in long food supply chains regarding their practices (open field vs greenhouses) and the kind of cultivar they use or wish to have.

International audience

International audience; Data fusion is a subject becoming increasingly relevant as scientists try to extract more and more information from remotely sensed data. Archives are growing, as well as the number of space missions devoted to Earth observation. It is generally correct to assume that improvements in terms of classification error probability, rejection rate, and interpretation robustness, can only be achieved at the expenses of additional independent data delivered by more separate sensors. Sensor data fusion allows to formalise the combination of these measurements, as well as to monitor the quality of information in the course of the fusion process. A Special Group of Interest ‘data fusion' has been established jointly within the European Association of the Remote Sensing Laboratories (EARSeL) and the French Society for Electricity and Electronics (SEE). This Group has defined several major tasks to be handled in order to increase our understanding and use of data fusion. One of these tasks is the establishment of terms of reference that are accepted by both the scientific and the industrial communities at least in Europe. A definition of the data fusion is proposed, which allows to set up a conceptual approach to the fusion of Earth observation data by putting an emphasis on the framework and on the fundamentals in remote sensing underlying data fusion. Several other definitions are given which are useful to describe any problem of data fusion.

International audience; Protected cultivation or Controlled Environment Agriculture (CEA) system has increased tenfold in the last 25 years thanks to tremendous scientific and technical breakthroughs, mainly directed to increasing crop yields and adapting to tough ambient conditions. Currently, greenhouse areas are still spreading and the CEA system is one of the keystones for the agriculture forecasting scenario. However, the environmental acceptability of this very intensive agro-ecosystem is now being questioned. Energy inputs are source of the main economic and environmental weakness, especially for high-tech greenhouses, where IPM is well-established. Pesticides, common in low-cost greenhouses systems, are a major barrier-to IPM. To design and manage more robust CEA systems, both technological and ecological approaches have been chosen. This allowed for increased consideration of IPM issues among global greenhouse engineering innovation and better use of greenhouse system capacities to enhance dedicated IPM high-tech tools and management practices. On the other hand, ecological concepts were used to determine and characterize complex biotic interactions that lead to question the tenant of biological control as soon as IPM is implemented in greenhouses with sub-optimum physical pest control means. More specifically, microclimate at the boundary layer level has been investigated both from a physical and biological point of view in order to determine the best climate preferences of the main pests and beneficials. By the same token, the efficiency of diverse biocontrol plants to provide accurate shelter to natural enemies has been assessed