Search results for "Forestry"
showing 10 items of 1998 documents
Land use functions — a multifunctionality approach to assess the impact of land use changes on land use sustainability
2008
Part 5. Regional and local evaluation - 17; International audience; The dramatic changes in land use observed in Europe in the last fifty years have generally resulted in improvement of human welfare and economic development. On the other hand, they have caused serious environmental problems. There is therefore a need for approaches that help to understand in an integrative way the economic, environmental and societal impacts that land use changes have on sustainability. Sustainability Impact Assessment(SIA), which assesses the impact of policies on sustainability, addresses this challenge. SIA partly builds on the concept of the multifunctionality of land which helps to deal with the compl…
Systèmes imageurs 3D pour des applications agricoles : caractérisation de cultures et phénotypage de racines
2016
The development of the concepts of precision agriculture and viticulture since the last three decades has shown the need to use first 2D image acquisition techniques and dedicated image processing. More and more needs concern now 3D images and information. The main ideas of this chapter is thus to present some innovations of the 3D tools and methods in the agronomic domain. This chapter will particularly focus on two main subjects such as the 3D characterization of crop using Shape from Focus or Structure from Motion techniques and the 3D use for root phenotyping using rhizotron system. Results presented show that 3D information allows to better characterize crucial crop morphometric parame…
Growth response of the saltbush Atriplex nummularia L. to inoculation with the arbuscular mycorrhizal fungus Glomus intraradices
2005
Abstract Plantlets of Atriplex nummularia were inoculated with the arbuscular mycorrhizal fungi Glomus intraradices in a pot experiment. Plants were grown in a low P soil. Highly significant growth response of a Chenopodiaceae was recorded for the first time. Mycorrhizal colonization of roots was well developed, internal hyphae and vesicles were observed, but not arbuscules. These observations suggest that arbuscules are not necessary to obtain significant growth stimulation from mycorrhizal inoculation. Atriplex nummularia is already used as forage crops, its high mycorrhizal dependency offers possibilities to develop this production and revegetation strategies.
Receptiveness of some tropical soils from banana fields in Martinique to the arbuscular fungus Glomus intraradices
2000
Tropical crops of great economic importance such as banana are known to benefit from mycorrhizal association. Development and survival of introduced mycorrhizal propagules depend not only on the crops but mainly on the edaphic conditions and soil types where the symbiosis is established. Seven soils from banana fields of Martinique were sampled and tested to determine their receptiveness to mycorrhizal inoculation. Biological tests involved cultivation of 10 leek plantlets in pots containing soil inoculated with a range of mycorrhizal propagule densities (3, 10, 30, 100, 300 propagules/100 g soil). Mycorrhizal colonisation was recorded after 2 weeks of growth and tentatively correlated with…
Broomrape weeds. Underground mechanisms of parasitism and associated strategies for their control: a review
2016
prod 2018-285d SPE GESTAD Agrosup INRA CT?; International audience; Broomrapes are plant-parasitic weeds which constitute one of the most difficult-to-control of all biotic constraints that affect crops in Mediterranean, central and eastern Europe, and Asia. Due to their physical and metabolic overlap with the crop, their underground parasitism, their achlorophyllous nature, and hardly destructible seed bank, broomrape weeds are usually not controlled by management strategies designed for non-parasitic weeds. Instead, broomrape are in a current state of intensification and spread due to lack of broomrape-specific control programs, unconscious introduction to new areas and may be decline of …
Trophic relationships between the parasitic plant species phelipanche ramosa (L.) and different hosts depending on host phenological stage and host g…
2016
Prod 2018-285c INRA AGROSUP GESTAD SPE CT3 SPE CT1 EJ2 EA; International audience; Phelipanche ramosa (L.) Pomel (branched broomrape) is a holoparasitic plant that reproduces on crops and also on weeds, which contributes to increase the parasite seed bank in fields. This parasite extracts all its nutrients at the host’s expense so that host–parasite trophic relationships are crucial to determine host and parasite growth. This study quantified the intensity with which P. ramosa draws assimilates from its host and analyzed whether it varied with host species, host phenological stage and host growth rate. A greenhouse experiment was conducted on three host species: the crop species Brassica na…
Evaluation of cropping systems for management of herbicide-resistant populations of blackgrass (Alopecurus myosuroides Huds.)
2001
Abstract Simplification of cropping systems often leads to an increase in weed populations which require an intensive use of herbicides to maintain populations at an acceptable level. Due to a heavy reliance on herbicides and a lack of cultural control measures, herbicide-resistant blackgrass (Alopecurus myosuroides Huds.) biotypes appeared recently in France. An experiment was conducted to evaluate the effects of different cropping systems on a population of herbicide-resistant blackgrass. Two crop rotations, one consisting exclusively of winter crops and another including spring crops, were assessed over a three-year period. Crop rotation was combined with different cultural practices (mo…
Reduced herbicide use does not increase crop yield loss if it is compensated by alternative preventive and curative measures
2018
Herbicide use must be reduced because of environmental and health issues. This raises the question of whether weeds and the resulting crop yield loss will increase. Previous studies analysing relationships between herbicide use intensity, weeds and yield loss suffer from methodological shortcomings in terms of weed flora and farm diversity as well as temporal scales. Here, we collected data on 272 arable cropping systems from one Spanish and six French regions, from farm surveys, the Biovigilance-Flore network, expert opinion, cropping system trials, crop advisors and scientists. Each system was simulated over 27 years and with 10 weather repetitions, using the virtual-field model FlorSys. …
Depth matters : Effects of precipitation regime on soil microbial activity upon rewetting of a plant-soil system
2018
International audience; Climate change is predicted to affect not only the amount but also the temporal distribution of rain. Changes in frequency and amplitude of rain events, i.e. precipitation patterns, result in different water conditions with soil depth, and likely affect plant growth and shape plant and soil microbial activity. Here, we used 18O stable isotope probing (SIP) to investigate bacterial and fungal communities that actively grew or not upon rewetting, at three different depths in plant-soil mesocosms previously subjected to frequent or infrequent watering for 12 weeks (equal total water input). Phylogenetic marker genes for bacteria and fungi were sequenced after rewetting,…
Qualité et performance de plants de Douglas soumis à différentes contraintes hydriques
1999
An experiment was carried out on 12 Douglas fir seedlings lots that were 3 years old and had all originated from the same seed lot. Treatments consisted in combining stock type with three different height to diameter ratios, storage duration and method (long at 2°C or short in various conditions), and protection from desiccation (by bagging or not). Seedling lots were assessed at planting by root electrolyte leakage (REL), root moisture content (RMC) and predawn shoot water potential (Ywp). They were planted simultaneously in well-watered or water-stressed conditions. Performance level was based on survival and height growth at the end of the growing season. Slender seedlings not bagged had…