Search results for "roots"
showing 10 items of 380 documents
Power of Paradox: Grassroots Organizations’ Legitimacy Strategies Over Time
2021
Fringe stakeholders with limited resources, such as grassroots organizations (GROs), are often ignored in business and society literature. We develop a conceptual framework and a set of propositions detailing how GROs strategically gain legitimacy and influence over time. We argue that GROs encounter specific paradoxes over the emergence, development, and resolution of an issue, and they address these paradoxes using cognitive, moral, and pragmatic legitimacy strategies. While cognitive and moral strategies tend to be used consistently, the flexible and paradoxical use of pragmatic strategies has important consequences, both for GROs’ legitimacy and for their potential influence over powerf…
Microbiological control of soil-borne phytopathogenic fungi with special emphasis on wilt-inducing Fusarium oxysporum
2009
Contents Summary 529 I. Biological control of plant diseases: state of the art 530 II. Main modes of action of biological control agents 530 III. The protective strains of F. oxysporum: an unexplored model 532 IV. Future directions for the study of the protective capacity of strains of F. oxysporum 539 V. How to make biological control successful in the field? 540 References 541 Summary Plant diseases induced by soil-borne plant pathogens are among the most difficult to control. In the absence of effective chemical control methods, there is renewed interest in biological control based on application of populations of antagonistic micro-organisms. In addition to Pseudomonas spp. a…
Proteomics as a tool to monitor plant-microbe endosymbioses in the rhizosphere
2004
In recent years, outstanding molecular approaches have been used to investigate genes and functions involved in plant-microbe endosymbioses. In this review, we outline the use of proteomic analysis, based on two-dimensional electrophoresis and mass spectrometry, to characterize symbiosis-related proteins. During the last decade, proteomics succeeded in identifying about 400 proteins associated with the development and functioning of both mycorrhizal and rhizobial symbioses. Further progress in prefractionation procedures is expected to allow the detection of symbiotic proteins showing low abundance or being present in certain cell compartments.
Sub-cellular proteomic analysis of a Medicago truncatula root microsomal fraction
2004
Since the last decade, Medicago truncatula has emerged as one of the model plants particularly investigated in the field of plant-microbe interactions. Several genetic and molecular approaches including proteomics have been developed to increase knowledge about this plant species. To complement the proteomic data, which have mainly focused on the total root proteins from M. truncatula, we carried out a sub-cellular approach to gain access to the total membrane-associated proteins. Following the setting up of the purification process, microsomal proteins were separated on 2-DE. Ninety-six out of the 440 well-resolved proteins were identified by MALDI-TOF peptide mass fingerprinting. A high p…
A proteomic approach to studying plant response to crenate broomrape (Orobanche crenata) in pea (Pisum sativum)
2004
Abstract Crenate broomrape ( Orobanche crenata ) is a parasitic plant that threatens legume production in Mediterranean areas. Pea ( Pisum sativum ) is severely affected, and only moderate levels of genetic resistance have so far been identified. In the present work we selected the most resistant accession available (Ps 624) and compared it with a susceptible (Messire) cultivar. Experiments were performed by using pot and Petri dish bioassays, showing little differences in the percentage of broomrape seed germination induced by both genotypes, but a significant hamper in the number of successfully installed tubercles and their developmental stage in the Ps 624 compared to Messire. The prote…
Identification of Trans-Golgi Network Proteins in Arabidopsis thaliana Root Tissue
2014
Knowledge of protein subcellular localization assists in the elucidation of protein function and understanding of different biological mechanisms that occur at discrete subcellular niches. Organelle-centric proteomics enables localization of thousands of proteins simultaneously. Although such techniques have successfully allowed organelle protein catalogues to be achieved, they rely on the purification or significant enrichment of the organelle of interest, which is not achievable for many organelles. Incomplete separation of organelles leads to false discoveries, with erroneous assignments. Proteomics methods that measure the distribution patterns of specific organelle markers along densit…
Mutations in DMI3 and SUNN modify the appressorium-responsive root proteome in arbuscular mycorrhiza.
2006
Modification of the Medicago truncatula root proteome during the early stage of arbuscular mycorrhizal symbiosis was investigated by comparing, using two-dimensional electrophoresis, the protein patterns obtained from non-inoculated roots and roots synchronized for Glomus intraradices appressorium formation. This approach was conducted in wild-type (J5), mycorrhiza-defective (TRV25, dmi3), and autoregulation-defective (TR122, sunn) M. truncatula genotypes. The groups of proteins that responded to appressorium formation were further compared between wild-type and mutant genotypes; few overlaps and major differences were recorded, demonstrating that mutations in DMI3 and SUNN modified the ap…
Informal Learning for Citizenship Building in Shared Struggles for Right: Cases of Political Solidarity Between Colombian and Spanish Organisations
2015
[EN]: Dominant discourses and practices in international cooperation have been characterised by depoliticisation and unequal power relationships. However, a number of more transformative experiences of cooperation also exist, where joint work between Northern and Southern social organisations is linked with a more political perspective. These kinds of experiences can be considered processes of informal learning in social action: through shared actions, strategies and frameworks and through interaction between organisations, institutions and the grassroots, informal and multidimensional learning processes occur in the people and organisations engaged. The study approaches four cases of netwo…
Chemical composition and antibacterial activity of essential oil of Pulicaria odora L.
2004
The chemical composition of the volatile oil constituent from Pulicaria odora L. roots has been analyzed by GC/MS. Twenty-seven components were identified, being thymol (47.83%) and its derivative isobutyrate (30.05%) the main constituents in the oil. Furthermore, the oil was tested against seven bacteria at different concentrations. Results showed that the oil exhibited a significant antibacterial activity.
The volume of geodesic balls and tubes about totally geodesic submanifolds in compact symmetric spaces
1997
AbstractLet M be a compact Riemannian symmetric space. We give an analytical expression for the area and volume functions of geodesic balls in M and for the area and volume functions of tubes around some totally geodesic submanifolds P of M. We plot the graphs of these functions for some compact irreducible Riemannian symmetric spaces of rank two.