Search results for "Propagation"
showing 10 items of 676 documents
Ambroisie, pourquoi un tel succès ?
2007
National audience
Managing crop nitrogen and soil dynamics
2001
Despite extensive research grain legume seed protein content and yield remains low and unstable. Grain legume performances in the cropping system are highly dependent upon N nutrition of the crop relying on root assimilation of soil N in combination with symbiotic fixation of atmospheric dinitrogen. In order to improve the competitive ability of grain legumes for growth resources an enlargement of the crop surface area production in combination with a judicious management of both inputs and N acquisition (and allocation to the harvested organs) is needed. Competitive ability implies to take into account economical constraints and the crop production effect on the environment, reducing the a…
In vitro biotechnology approaches now available for ‘beautiful’ vavilovia (Vavilovia formosa)
2014
BAP Pôle GEAPSI; Efficient in vitro propagation of Vavilovia formosa, plant regeneration from callus, protoplast isolation and culture to differentiated callus of V.formosa were developed and its relative nuclear DNA content by flow cytometry was established. The summation of biotechnology tools now available should foster evolutionary studies on the tribe Fabeae and, intime, V.formosa could be come a potential source of novel agronomic adaptive traits.
Environmental spillovers and their impacts on housing prices: A spatial hedonic analysis
2015
This paper investigates the spatial dimension of environmental factors on housing prices. We develop spatial hedonic models to estimate the implicit prices of various environmental attributes. The spatial dimension can be interpreted in terms of local or global spillovers. We conduct an empirical study in the Loire estuary (France). We focus on natural areas and more artificialized ones (ocean frontage, wetlands, rivers, and noisy roads). We show that, depending on the spatial model used, the implicit price is more than just the estimated coefficient value and combines both a feedback effect and a propagation effect.
Guidance of surface elastic waves along a linear chain of pillars
2016
International audience; The propagation of surface elastic waves, or surface phonons, is considered along a linear and periodic chain of cylindrical pillars sitting on a semi-infinite solid substrate. A variety of guided modes, some of them exhibiting a very low group velocity, are shown to exist at frequencies close to the resonance frequencies of the pillars. Although the pillar diameter is typically smaller than half the relevant wavelength, lateral radiation on the surface is found to be canceled. Surface guidance is explained by the hybridization of the resonating pillars with the continuum of elastic waves of the substrate.
Three-Dimensional Simulations of Solar Wind Preconditioning and the 23 July 2012 Interplanetary Coronal Mass Ejection
2020
Predicting the large-scale eruptions from the solar corona and their propagation through interplanetary space remains an outstanding challenge in solar- and helio-physics research. In this article, we describe three dimensional magnetohydrodynamic simulations of the inner heliosphere leading up to and including the extreme interplanetary coronal mass ejection (ICME) of 23 July 2012, developed using the code PLUTO. The simulations are driven using the output of coronal models for Carrington rotations 2125 and 2126 and, given the uncertainties in the initial conditions, are able to reproduce an event of comparable magnitude to the 23 July ICME, with similar velocity and density profiles at 1 …
Micropropagation of Genista aetnensis [(Raf. ex Biv.)DC]
2015
Genista aetnensis [(Raf. ex Biv.)DC] is a large deciduous shrub or small tree native to the Italian islands of Sardinia and Sicily. Being winter hardy and characterized by high plasticity in altitude and ecology, the species is grown in gardens and landscaping, both for flower and for its attractive shape. Genista species are generally propagate by seed or semi hardwood cuttings. In this report an efficient in vitro technique for propagation of G. aetnensis was investigated. Multiple shoots were induced on nodal segments of a mature plant of Genista aetnensis . The Murashige and Skoog medium, augmented with different concentrations of benzyladenine either singly or in combination with indol…
Plant hormones and Agrobacterium tumefaciens strain 82.139 induce efficient plant regeneration in the cardenolide-producing plant Digitalis minor
2002
Summary Shoot formation in explants of Digitalis minor was achieved, through axillary bud proliferation and adventitious bud differentiation, by varying the amount and source of plant hormones. Shoot regeneration was also obtained after infection of D. minor with the wild-type Agrobacterium tumefaciens strain 82.139, which induced shooty tumours. These shoots were not transgenic, as revealed by nopaline assays and the use of a C58pMP90/T139GUS-INT strain harbouring the intron inactivated gusA gene. Plants were easily rooted and transplanted into the greenhouse. Shoot cultures of D. minor accumulated up to 226 μg cardenolides per g dry mass when cultured on agar-solidified medium. Cardenolid…
Plant regeneration from juvenile and adult Anthyllis cytisoides, a multipurpose leguminous shrub
1997
Summary Anthyllis cytisoides , a legume shrub used for afforestation and reclamation of degraded Mediterranean areas, was successfully micropropagated from expiants of juvenile (cotyledonary nodes and apical buds) and adult origin (axillary buds). Multiple shoot formation was dependent on the presence of benzyladenine in the induction medium. Of the salt formulation and expiants examined, the higher proliferation rates were obtained when axillary buds from adult plants were cultured on a modified Schenk and Hildebrandt medium. Following the preferred protocol, shoot yield reached values greater than 100 shoots per expiant. Plants were easily rooted and transplanted into greenhouse.
Selection and long-term cultures of high-yielding Digitalis obscura plants: RAPD markers for analysis of genetic stability
1996
Fifteen wild-growing plants of Digitalis obscura collected in three differents regions were characterized according to their capacities to biosynthesize cardenolides and to proliferate in vitro. Great genotype-dependent variabilities were found in both parameters. Selected genotypes were differentiated using randomly amplified polymorphic DNA (RAPD) markers. Once an elite genotype with high-yielding properties was isolated and micropropagated during 2 years, identity of the donor plant and the regenerants was confirmed by RAPD analysis.