Search results for "Defense"
showing 10 items of 247 documents
Nuclear protein acetylation in the control of plant defense responses: role of type-2 histone deacetylases
2015
Effect of commercially available Plant Defence Stimulators on human innate immunity
2015
PDS (Plant defence stimulators) constitute a recent alternative to pesticides used for crop protection. These compounds are of diverse nature, they all act by stimulating plant innate immune system and plants can better fight pathogens. There are many similarities in pathogen perception systems and cellular signalling in plants and animals. Many elicitors stimulate both human and plant innate immunity (Zipfel and Felix, 2005). Therefore, it is likely that human innate immunity could be modulated by PDS. The aim of this study is to evaluate pro/anti-inflammatory activity of five different commercially available PDS on human cell models. We studied the pro/anti-inflammatory effect of PDS on h…
Impact des maladies du bois sur le fonctionnement de la vigne
2020
Esca complex and Botryosphearia dieback are grapevine trunk diseases (GTDs) that cause severe declines in vineyards worldwide and against which the available control strategies are limited. These diseases are due to a complex of woody inhabiting fungi that colonize the perennial organs of grapevine throughout its life, from its production in nursery to the cultivation in the vineyard. The expression of foliar symptoms remains poorly understood and is influenced by many factors including climate, cultural practices and cultivar. In this context, this work aimed to characterize the impact of these two diseases on grapevine, at different spatial and temporal scales, in order to better understa…
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…
Dual mode of action of grape cane extracts against Botrytis cinerea
2019
International audience; Crude extracts of Vitis vinifera canes represent a natural source of stilbene compounds with well characterized antifungals properties. In our trials, exogenous application of a stilbene extract (SE) obtained from grape canes on grapevine leaves reduces the necrotic lesions caused by Botrytis cinerea. The SE showed to possess a direct antifungal activity by inhibiting the mycelium growth. The activation of some grapevine defense mechanism was also investigated. H2O2 production and activation of mitogen-activated protein kinase (MAPK) phosphorylation cascades as well as accumulation of stilbenoid phytoalexins were explored on grapevine cell suspension. Moreover, the t…
Comparative analysis of PR gene expression in tomato inoculated with virulent Fusarium oxysporum f. sp. lycopersici and the biocontrol strain F. oxys…
2008
Non-pathogenic strains of Fusarium oxysporum have the capacity to protect plants against wilt induced by pathogenic strains of F. oxysporum. Among the mechanisms involved in this protection, induced systemic resistance has been demonstrated by using a split-root method. The aim of this study was to follow the accumulation kinetics of transcripts encoding 5 PR proteins in roots and leaves of tomato inoculated with a pathogenic or a protective strain in comparison to non-inoculated control. Moreover quantification of transcripts was assessed by real-time RT-PCR in cell cultures inoculated with the pathogenic or the protective strain. Results showed a lower expression of PR encoding genes in t…
Tantalo e la ricerca dello spazio-tempo perduto: riflessioni a margine della tutela cautelare nel processo amministrativo e di altri demoni
2020
The paper pays attention to the concrete dynamics inside the precautionary phase of the administrative trial
De novo Synthesis of Chemical Defenses in an Aposematic Moth
2018
Many animals protect themselves from predation with chemicals, both self-made or sequestered from their diet. The potential drivers of the diversity of these chemicals have been long studied, but our knowledge of these chemicals and their acquisition mode is heavily based on specialist herbivores that sequester their defenses. The wood tiger moth (Arctia plantaginis, Linnaeus, 1758) is a well-studied aposematic species, but the nature of its chemical defenses has not been fully described . Here, we report the presence of two methoxypyrazines, 2-sec-butyl-3-methoxypyrazine and 2-isobutyl-3-methoxypyrazine, in the moths’ defensive secretions. By raising larvae on an artificial diet, we confir…
Evolution of vertebrate survival circuits
2018
Evolution selects those adaptive features that increase reproductive probabilities and facilitate survival. Analysing the brain circuits mediating risk-avoidance (e.g. defense) and those allowing reward-seeking (motivated) behaviours in different vertebrates leads to several main conclusions. First, circuits mediating risk-avoidance are similar in all studied vertebrates, where they include amygdala homologues located in the posterior half of the cerebral hemispheres, in close relationship with the chemosensory systems. Second, in all vertebrates, reward-seeking behaviours involve the activity of tegmento-striatal dopaminergic pathways, plus other inputs to the ventral striatum, including a…
Dithiodiketopiperazine derivatives from endophytic fungi Trichoderma harzianum and Epicoccum nigrum
2021
A new epidithiodiketopiperazine (ETP), pretrichodermamide G (1), along with three known (epi)dithiodiketopiparazines (2-4) were isolated from cultures of Trichoderma harzianum and Epicoccum nigrum, endophytic fungi associated with medicinal plants Zingiber officinale and Salix sp., respectively. The structure of the new compound (1) was established on the basis of spectroscopic data, including 1D/2D NMR and HRESIMS. The isolated compounds were investigated for their antifungal, antibacterial and cytotoxic potential against a panel of microorganisms and cell lines. Pretrichodermamide A (2) displayed antimicrobial activity towards the plant pathogenic fungus Ustilago maydis and the human path…