Advanced search in
Research products
arrow_drop_down
Searching FieldsTerms
Any field
arrow_drop_down
includes
arrow_drop_down
Include:
4,181 Research products, page 1 of 419

  • Conference object
  • FR
  • English
  • Hyper Article en Ligne
  • Mémoires en Sciences de l'Information et de la Communication
  • Hal-Diderot
  • Rural Digital Europe

10
arrow_drop_down
Relevance
arrow_drop_down
  • English
    Authors: 
    Christine Poncet; Cécile Bresch; Hicham Fatnassi; Ludovic Mailleret; Alexandre Bout; G. Perez; Jeannine Pizzol; L. Carlesso; B. Paris; Pia Parolin;
    Publisher: HAL CCSD
    Country: France
    Project: EC | PURE (265865)

    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

  • Open Access English
    Authors: 
    Chignier-Riboulon Franck; Mauricette Fournier;
    Publisher: HAL CCSD
    Country: France

    International audience; Marvejols is a small town located in Lozère (France). Traditionally, the region was poor with an agricultural oriented economy. However, by the 1960s a new type of business was launched: the residential care facilities for disabled people, especially in relation to Jacques Blanc, a key person in the organization and development of this business. This economic activity brought jobs and new attractiveness, counterbalancing decline in traditional sectors. Nevertheless, currently, situation is less favourable, and the local players try to find out a new strategy, particularly in relation to diversification. In this study, our main aim was to understand conditions of starting and growing of this business. Moreover, we would like to understand current fragilities and attempts to adapt the economy of the territory. In this way, our students and we have chosen this area in relation to the economic and historical weight of its activity. The organization of field trips and survey was conducted in a comprehensive approach perspective. Therefore, we took account parameters working in this territory, such as strategies, psychologies (individual and collective), networks and identities. Human dimensions are strong, especially in discourses, and our main result is a better understanding of the local situation, with comparisons to close cases (Corrèze, Creuse). Furthermore, the quality of the geographical analysis provides working relations with the stakeholders

  • English
    Authors: 
    Sergey Krivenko; Vladimir V. Lukin; Benoit Vozel; Kacem Chehdi;
    Publisher: HAL CCSD
    Country: France

    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.

  • English
    Authors: 
    M. Malnoy; E. Chevreau; M.N. Brisset;
    Publisher: HAL CCSD
    Country: France

    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.

  • Publication . Article . Conference object . 2000
    English
    Authors: 
    C. Poncet; G. Bonnet; S. Pionnat; D. Hericher; A. Bettachini;
    Publisher: HAL CCSD
    Country: France

    International audience

  • Publication . Conference object . Article . Other literature type . 1992
    Open Access English
    Authors: 
    Thierry Simonneau; Robert Habib; J.-P. Goutouly; J.-G. Huguet; A. Lecomte;
    Publisher: HAL CCSD
    Country: France

    International audience

  • English
    Authors: 
    Frederic Rey; Nicolas Sinoir; C. Mazollier; Véronique Chable;
    Publisher: HAL CCSD
    Country: France

    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.

  • Open Access English
    Authors: 
    L. Astigarraga; J. L. Peyraud; M. Le Bars;
    Publisher: HAL CCSD
    Country: France

    International audience

  • English
    Authors: 
    D. Morin; Milena Planelis; Dominique Guyett; Ludovic Viiiard; Gérard Dedieu;
    Publisher: HAL CCSD
    Country: France

    International audience; Forest monitoring is a major issue to carry out energetic and environmental policies. Actual context in spaceborne remote sensing data is very promising. Our study aims to test the ability of SAR, optical and textural data to estimate forest parameters (biomass, height, diameter and density), and to evaluate the improvement of combining these remote sensing data. We worked on monospecific pine forest stands. The first results highlighted the synergy between SAR and spatial texture informations. Sentinel-1 C-band SAR data is very promising for the estimation of forest parameters in monospecifics stands. Biomass was estimated with 29.4% relative error (20.7 tons/ha) and height with 14.6% (2.1m) combining four SAR and optical sensors.

  • Open Access English
    Authors: 
    Bei Cui; Wenjiang Huang; Huichun Ye; Qimin Cao;
    Publisher: HAL CCSD
    Country: France

    International audience; Studying the spatial distribution characters of rubber yield and soil nutrients and the rule of spatial variability are important for suitable fertilization strategy in rubber plantation. This paper selected Hongquan Branch, Guangba Branch and Gongai Branch of Guangba Farm in Hainan province as study area and total of 327 samples were selected in the rubber plantation. The spatial distribution characters of rubber yield and five soil nutrients, including organic matter (OM), total nitrogen (TN), available phosphorus (AP), available potassium (AK), exchangeable calcium (Ga), were studied using traditional analysis method and geo-statistics analysis method. The results showed that: (1) The average value of rubber yield was 3.55 kg/hm2 with moderate spatial variability and the average values of OM, N, P, K and Ga were 11.65 g/kg, 0.07%, 16.23 mg/kg, 49.65 mg/kg and 84.44 mg/kg, respectively. Soil OM, TN, AK and Ga had moderate spatial variability but AP had strong spatial variability. (2) Rubber yield and soil total nitrogen (N) nutrient had strong spatial dependence; soil OM, AP, AK and Ga had moderate spatial dependence. (3) Based on the previous reports of normal range of soil nutrients, soil OM and TN nutrient content were very low in the studied rubber plantation of Guangba Farm. Therefore, more nitrogen fertilizer should be applied in the rubber plantation in future.

Advanced search in
Research products
arrow_drop_down
Searching FieldsTerms
Any field
arrow_drop_down
includes
arrow_drop_down
Include:
4,181 Research products, page 1 of 419
  • English
    Authors: 
    Christine Poncet; Cécile Bresch; Hicham Fatnassi; Ludovic Mailleret; Alexandre Bout; G. Perez; Jeannine Pizzol; L. Carlesso; B. Paris; Pia Parolin;
    Publisher: HAL CCSD
    Country: France
    Project: EC | PURE (265865)

    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

  • Open Access English
    Authors: 
    Chignier-Riboulon Franck; Mauricette Fournier;
    Publisher: HAL CCSD
    Country: France

    International audience; Marvejols is a small town located in Lozère (France). Traditionally, the region was poor with an agricultural oriented economy. However, by the 1960s a new type of business was launched: the residential care facilities for disabled people, especially in relation to Jacques Blanc, a key person in the organization and development of this business. This economic activity brought jobs and new attractiveness, counterbalancing decline in traditional sectors. Nevertheless, currently, situation is less favourable, and the local players try to find out a new strategy, particularly in relation to diversification. In this study, our main aim was to understand conditions of starting and growing of this business. Moreover, we would like to understand current fragilities and attempts to adapt the economy of the territory. In this way, our students and we have chosen this area in relation to the economic and historical weight of its activity. The organization of field trips and survey was conducted in a comprehensive approach perspective. Therefore, we took account parameters working in this territory, such as strategies, psychologies (individual and collective), networks and identities. Human dimensions are strong, especially in discourses, and our main result is a better understanding of the local situation, with comparisons to close cases (Corrèze, Creuse). Furthermore, the quality of the geographical analysis provides working relations with the stakeholders

  • English
    Authors: 
    Sergey Krivenko; Vladimir V. Lukin; Benoit Vozel; Kacem Chehdi;
    Publisher: HAL CCSD
    Country: France

    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.

  • English
    Authors: 
    M. Malnoy; E. Chevreau; M.N. Brisset;
    Publisher: HAL CCSD
    Country: France

    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.

  • Publication . Article . Conference object . 2000
    English
    Authors: 
    C. Poncet; G. Bonnet; S. Pionnat; D. Hericher; A. Bettachini;
    Publisher: HAL CCSD
    Country: France

    International audience

  • Publication . Conference object . Article . Other literature type . 1992
    Open Access English
    Authors: 
    Thierry Simonneau; Robert Habib; J.-P. Goutouly; J.-G. Huguet; A. Lecomte;
    Publisher: HAL CCSD
    Country: France

    International audience

  • English
    Authors: 
    Frederic Rey; Nicolas Sinoir; C. Mazollier; Véronique Chable;
    Publisher: HAL CCSD
    Country: France

    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.

  • Open Access English
    Authors: 
    L. Astigarraga; J. L. Peyraud; M. Le Bars;
    Publisher: HAL CCSD
    Country: France

    International audience

  • English
    Authors: 
    D. Morin; Milena Planelis; Dominique Guyett; Ludovic Viiiard; Gérard Dedieu;
    Publisher: HAL CCSD
    Country: France

    International audience; Forest monitoring is a major issue to carry out energetic and environmental policies. Actual context in spaceborne remote sensing data is very promising. Our study aims to test the ability of SAR, optical and textural data to estimate forest parameters (biomass, height, diameter and density), and to evaluate the improvement of combining these remote sensing data. We worked on monospecific pine forest stands. The first results highlighted the synergy between SAR and spatial texture informations. Sentinel-1 C-band SAR data is very promising for the estimation of forest parameters in monospecifics stands. Biomass was estimated with 29.4% relative error (20.7 tons/ha) and height with 14.6% (2.1m) combining four SAR and optical sensors.

  • Open Access English
    Authors: 
    Bei Cui; Wenjiang Huang; Huichun Ye; Qimin Cao;
    Publisher: HAL CCSD
    Country: France

    International audience; Studying the spatial distribution characters of rubber yield and soil nutrients and the rule of spatial variability are important for suitable fertilization strategy in rubber plantation. This paper selected Hongquan Branch, Guangba Branch and Gongai Branch of Guangba Farm in Hainan province as study area and total of 327 samples were selected in the rubber plantation. The spatial distribution characters of rubber yield and five soil nutrients, including organic matter (OM), total nitrogen (TN), available phosphorus (AP), available potassium (AK), exchangeable calcium (Ga), were studied using traditional analysis method and geo-statistics analysis method. The results showed that: (1) The average value of rubber yield was 3.55 kg/hm2 with moderate spatial variability and the average values of OM, N, P, K and Ga were 11.65 g/kg, 0.07%, 16.23 mg/kg, 49.65 mg/kg and 84.44 mg/kg, respectively. Soil OM, TN, AK and Ga had moderate spatial variability but AP had strong spatial variability. (2) Rubber yield and soil total nitrogen (N) nutrient had strong spatial dependence; soil OM, AP, AK and Ga had moderate spatial dependence. (3) Based on the previous reports of normal range of soil nutrients, soil OM and TN nutrient content were very low in the studied rubber plantation of Guangba Farm. Therefore, more nitrogen fertilizer should be applied in the rubber plantation in future.

Send a message
How can we help?
We usually respond in a few hours.