Search results for "botany"
showing 10 items of 4586 documents
Methods for studying root colonization by introduced beneficial bacteria
2003
e-Book; Some free-living rhizobacteria are considered as potential biocontrol and plant growth-promoting agents. Successful application of beneficial bacteria as microbial inoculants requires their presence and activity at the appropriate level, but even more, at the right time and place. Various markers are described in the literature to differentiate introduced bacteria from indigenous microflora and to visualize them. These markers are presented together with the methods currently applied to quantify bacterial densities and to characterize the distribution of introduced bacteria. The methods to quantify bacterial densities are either based on bacterial cultivation or not. Different types…
Characterization of rhizobia nodulating chickpea in Tunisia
2001
Cent cinquante rhizobia nodulant le pois chiche (Cicer arietinum L.) ont ete isoles a partir de sols echantillonnes dans differentes regions de Tunisie. L'inoculation de la plante hote avec ces isolats montre une variabilite dans le temps d'apparition des premieres nodosites. Cinq isolats induisent des nodosites deux semaines apres inoculation alors que pour les 145 isolats restants les nodosites ne sont observees qu'apres au moins quatre semaines. L'etude par PCR/RFLP de l'ADNr 16S a permis de rattacher les isolats du premier groupe a l'espece Mesorhizobium mediterraneum et ceux du second groupe a l'espece Sinorhizobium medicae. La position taxonomique des isolats a ete confirmee par leurs…
Storage cells – oil and protein bodies
2016
BAPGEAPSI; Molecular Cell Biology of the Growth and Differentiation of Plant Cells encompasses cell division, cell enlargement and differentiation; which is the cellular basis of plant growth and development. Understanding these developmental processes is fundamental for improving plant growth and the production of special plant products, as well as contributing to biological understanding. The dynamics of cells and cellular organelles are considered in the context of growth and differentiation, made possible particularly by advances in molecular genetics and the visualization of organelles using molecular probes. There is now a much clearer understanding of these basic plant processes of c…
Sulfate transporters in the plant’s response to drought and salinity: regulation and possible functions
2014
International audience; Drought and salinity are two frequently combined abiotic stresses that affect plant growth, development, and crop productivity. Sulfate, and molecules derived from this anion such as glutathione, play important roles in the intrinsic responses of plants to such abiotic stresses. Therefore, understanding how plants facing environmental constraints re-equilibrate the flux of sulfate between and within different tissues might uncover perspectives for improving tolerance against abiotic stresses. In this review, we took advantage of genomics and post-genomics resources available in Arabidopsis thaliana and in the model legume species Medicago truncatula to highlight and …
Copper binding capacity of root exudates of cultivated plants and associated weeds
2001
International audience; Cu binding to root exudates of two cultivated plants, wheat (Triticum aestivum) and rape (Brassica napus), and two weeds associated with wheat, dog daisy (Matricaria inodora) and cornflower (Centaurea cyanus), was studied in vitro under hydroponic and sterile conditions. Nutrient solutions were prepared with or without P. A MetPLATE microbiological test was used to assess the metal complexing capacity of root exudates. In the P-deficient solutions, no exudation was observed for any of the four plants; consequently, no Cu binding occurred. When P was present in the nutrient solutions, the plant exudates displayed differing abilities to complex Cu. No difference was de…
Sesquiterpene volatile organic compounds (VOCs) are markers of elicitation by sulfated laminarine in grapevine
2015
SPE IPM UB CT1; International audience; Inducing resistance in plants by the application of elicitors of defense reactions is an attractive plant protection strategy, particularly for grapevine (Vitis vinifera), which is susceptible to severe fungal diseases. Although induced resistance (IR) can be successful under controlled conditions, in most cases, IR is not sufficiently effective for practical disease control under outdoor conditions. Progress in the application of IR requires a better understanding of grapevine defense mechanisms and the ability to monitor defense markers to identify factors, such as physiological and environmental factors, that can impact IR in the vineyard. Volatile…
Diversity and complexity of microbial communities from a chlor-alkali tailings dump
2015
Abstract Revegetation of the tailings dumps produced by various industrial activities is necessary to prevent dust storms and erosion and represents a great challenge for ecological restoration. Little is known about the microbial colonisation and community structure of revegetated tailings following site exploitation. Here, we report the sequencing of 16S rRNA and internal transcribed spacer (ITS) fungal RNA gene amplicons from chlor-alkali residue and from an adjacent undisturbed soil to define the composition and assembly of the rhizosphere microbial communities. After quality filtering, a total of 72,373 and 89,929 bacterial sequences and 122,618 and 111,209 fungal sequences remained fo…
Two new species of the genus Ochroconis, O. lascauxensis and O. anomala isolated from black stains in Lascaux Cave, France
2012
In the year 2001, some conspicuous black stains appeared on the walls of Lascaux Cave in France, which progressively disseminated throughout the cave. These black stains were so evident by 2007 that they have become one of the cave's major problems. In a mycological study of the black stains, Ochroconis strains were abundant among the isolates and constituted the major group of melanised fungi. Two new species of the genus Ochroconis, O. lascauxensis and O. anomala, were isolated and described. The description is based on the morphology of the fungi and the phylogenetic relationships of two of its gene regions internal transcribed spacer (ITS) and RNA polymerase II subunit B (RPB2). In addi…
The Largest Subunit of RNA Polymerase II as a New Marker Gene to Study Assemblages of Arbuscular Mycorrhizal Fungi in the Field
2014
Due to the potential of arbuscular mycorrhizal fungi (AMF, Glomeromycota) to improve plant growth and soil quality, the influence of agricultural practice on their diversity continues to be an important research question. Up to now studies of community diversity in AMF have exclusively been based on nuclear ribosomal gene regions, which in AMF show high intra-organism polymorphism, seriously complicating interpretation of these data. We designed specific PCR primers for 454 sequencing of a region of the largest subunit of RNA polymerase II gene, and established a new reference dataset comprising all major AMF lineages. This gene is known to be monomorphic within fungal isolates but shows an…
Grafengruft in neuer Würde - die Grablege derer von Ehrentreuter/ von Wedel unter der reformierten Kirche in Loga/ Leer
2018
International audience