Search results for "rhizosphere"
showing 10 items of 112 documents
The responses of shoot-root-rhizosphere continuum to simultaneous fertilizer addition, warming, ozone and herbivory in young Scots pine seedlings in …
2017
Abstract It is not clear how climate change in combination with increasing soil nitrogen availability and herbivory affects boreal forests, the largest terrestrial biome in the world. In this study, Scots pine ( Pinus sylvestris ) seedlings were exposed to moderate warming (ca. 1 °C), 1.5 × ambient ozone (O 3 ) concentration, fertilizer addition (120 kg N ha −1 yr −1 ) and shoot herbivory by pine sawfly ( Acantholyda posticalis ) alone and in combination. We measured fine root morphology, mycorrhizal colonization level, root fungal biomass (ergosterol), rhizosphere emission of biogenic volatile organic compounds (BVOCs), and microbial biomass (PLFAs) in the rhizosphere soil as well as seedl…
Allelopathy and the role of allelochemicals in plant defence
2017
International audience; Allelopathy is described as the interference to plant growth resulting from chemical interactions among plants and other organisms mediated through release of plant-produced bioactive secondary metabolites referred to as allelochemicals. A number of mechanisms have been studied for the release of allelochemicals from various plant tissues including volatilization or leaching from aerial parts, exudation from roots and decomposition of plant residues in soil. Despite differences in biological activity and mode of action, related compounds commonly share similar biosynthetic pathways while some classes of metabolites can be produced using diverse biosynthetic pathways.…
Use of plant growth-promoting rhizobacteria (PGPR) and organic fertilization for soilless cultivation of basil
2021
Abstract Today there is a greater environmental and ecological awareness and it is growing the number of farmers who want to adopt sustainable and efficient cultivation systems even if not officially certified as organic. Sustainable and modern cultivation systems must involve organic fertilization and cannot ignore the role of rhizosphere microorganisms. Starting from this premise, this paper aimed to evaluate the use of plant growth-promoting rhizobacteria (PGPR) and organic liquid fertilizers on soilless cultivation of basil. Genovese basil plants were cultivated in pots filled with a substrate inoculated or not with a commercial biostimulant (TNC BactorrS13) containing growth-promoting …
Woody Plant Declines. What’s Wrong with the Microbiome?
2020
National audience; Woody plant (WP) declines have multifactorial determinants as well as a biological and economic reality. The vascular system of WPs involved in the transport of carbon, nitrogen, and water from sources to sinks has a seasonal activity, which places it at a central position for mediating plant–environment interactions from nutrient cycling to community assembly and for regulating a variety of processes. To limit effects and to fight against declines, we propose: (i) to consider the WP and its associated microbiota as an holobiont and as a set of functions; (ii) to consider simultaneously, without looking at what comes first, the physiological or pathogenic disorders; and (…
Impact of Bacterial Siderophores on Iron Status and Ionome in Pea
2020
National audience; Including more grain legumes in cropping systems is important for the development of agroecological practices and the diversification of protein sources for human and animal consumption. Grain legume yield and quality is impacted by abiotic stresses resulting from fluctuating availabilities in essential nutrients such as iron deficiency chlorosis (IDC). Promoting plant iron nutrition could mitigate IDC that currently impedes legume cultivation in calcareous soils, and increase the iron content of legume seeds and its bioavailability. There is growing evidence that plant microbiota contribute to plant iron nutrition and might account for variations in the sensitivity of pe…
Take a Trip Through the Plant and Fungal Transportome of Mycorrhiza
2016
International audience; Soil nutrient acquisition and exchanges through symbiotic plant–fungus interactions in the rhizosphere are key features for the current agricultural and environmental challenges. Improved crop yield and plant mineral nutrition through a fungal symbiont has been widely described. In return, the host plant supplies carbon substrates to its fungal partner. We review here recent progress on molecular players of membrane transport involved in nutritional exchanges between mycorrhizal plants and fungi. We cover the transportome, from the transport proteins involved in sugar fluxes from plants towards fungi, to the uptake from the soil and exchange of nitrogen, phosphate, p…
Plants and Arbuscular Mycorrhizal Fungi: Cues and Communication in the Early Steps of Symbiotic Interactions
2007
Abstract The ubiquitous nature of arbuscular mycorrhiza (AM) pleads for common molecular and genetic determinants across different plant taxa. The cellular processes determining compatibility in early interactions prior to and during cell contact between arbuscular mycorrhizal fungi and plant roots are starting to be unraveled. The root epidermis is an active checkpoint where signal exchanges and control over root colonization occur. Root‐secreted flavonoids, flavonols, and strigolactones can act as rhizosphere signals in stimulating presymbiotic fungal growth, although their mechanism of action on the fungal cell is as yet unknown. Likewise, fungal signals (Myc factors) activate early plan…
Colonization of Plant Roots by Pseudomonads and AM Fungi: A Dynamic Phenomenon, Affecting Plant Growth and Health
2008
Because of their enormously large range of plant hosts and role in plant nutrition, arbuscular mycorrhizal (AM) fungi represent an extraordinarily fascinating field of study. Plant growth promotion effects by AM fungi were described as early as 1900 (Sthal 1900) and several data obtained in the second half of the last century support the idea that these microrganisms can act as biocontrol agents (BCA). The extent of root colonization is variable in different plants and under different environmental conditions (Giovannetti and Hepper 1985). Some effects of AM colonization on plants have been reported to be dependent on the degree of root colonization, while others have not. Root exudation an…
Editorial: Exploring Plant Rhizosphere, Phyllosphere and Endosphere Microbial Communities to Improve the Management of Polluted Sites
2021
International audience
The rhizosphere of mycorrhizal plants
2002
Providing that appropriate carbon substrates are available, microbial communities are able to develop a range of activities which are crucial in maintaining a biological balance in soil (Bowen and Rovira 1999), a key issue for the sustainability of either natural ecosystems or agroecosystems (Kennedy and Smith 1995). Soil-borne microbes have a particular microhabitat in which to flourish. In particular, they are bound to the surface of soil particles or found in soil aggregates, while others interact specifically with the plant root system (Glick 1995). The root-soil interface is actually a dynamic changing environment, a microcosm where microorganisms, plant roots and soil constituents int…