Search results for "plant pathology"

Multitrophic interactions in the rhizosphere Rhizosphere microbiology: at the interface of many disciplines and expertises.

2008

The rhizosphere – the soil compartment influenced by the root, including the root itself – is the most-active microbial habitat in soils. Indeed, the release by plant roots of a significant part of their photosynthates promotes microbial abundance and activities in the rhizosphere. This investment made by plants is paid back by microbial functions, which contribute to plant nutrition and protection against soil-borne diseases. Indeed, rhizosphere microorganisms play a major role in plant growth and health and, …

Molecular methods for the diagnosis and characterization of phytopathogenic fungi of quarantine concern or causing emerging plant diseases

2021

In the context of molecular techniques applied to Plant Pathology, this Ph.D. thesis has pursued the following major objectives: i) to develop new diagnostic protocols for fungal pathogens; ii) to study the metabolic and physiological effects determined by new and emerging fungal pathogens; iii) to contribute to develop management strategies of diseases caused by quarantine and/or emerging fungi on plant species typical of the Mediterranean region. To fulfill these objectives, the following specific studies have been developed: • “Fusarium circinatum an emergent and quarantine pathogen of pine worldwide: its detection and its interaction with Phytophthora species (P. cambivora and P. parvis…

Molecular signatures of silencing suppression degeneracy from a complex RNA virus

2021

As genomic architectures become more complex, they begin to accumulate degenerate and redundant elements. However, analyses of the molecular mechanisms underlying these genetic architecture features remain scarce, especially in compact but sufficiently complex genomes. In the present study, we followed a proteomic approach together with a computational network analysis to reveal molecular signatures of protein function degeneracy from a plant virus (as virus-host protein-protein interactions). We employed affinity purification coupled to mass spectrometry to detect several host factors interacting with two proteins of Citrus tristeza virus (p20 and p25) that are known to function as RNA sil…

Arbuscular mycorrhizal symbiosis mitigates the negative effects of salinity on durum wheat

2017

Arbuscular mycorrhizal (AM) symbiosis is generally considered to be effective in ameliorating the plant tolerance to salt stress. Unfortunately, the comprehension of the mechanisms implicated in salinity stress alleviation by AM symbiosis is far from being complete. Thus, an experiment was performed by growing durum wheat (Triticum durum Desf.) plants under salt-stress conditions to evaluate the influence of AM symbiosis on both the plant growth and the regulation of a number of genes related to salt stress and nutrient uptake. Durum wheat plants were grown outdoors in pots in absence or in presence of salt stress and with or without AM fungi inoculation. The inoculum consisted of a mixture…

Shared midgut binding sites for Cry1A.105, Cry1Aa, Cry1Ab, Cry1Ac and Cry1Fa proteins from Bacillus thuringiensis in two important corn pests, Ostrin…

2013

First generation of insect-protected transgenic corn (Bt-corn) was based on the expression of Cry1Ab or Cry1Fa proteins. Currently, the trend is the combination of two or more genes expressing proteins that bind to different targets. In addition to broadening the spectrum of action, this strategy helps to delay the evolution of resistance in exposed insect populations. One of such examples is the combination of Cry1A.105 with Cry1Fa and Cry2Ab to control O. nubilalis and S. frugiperda. Cry1A.105 is a chimeric protein with domains I and II and the C-terminal half of the protein from Cry1Ac, and domain III almost identical to Cry1Fa. The aim of the present study was to determine whether the c…

Caracterización y diagnóstico molecular de las cepas de Colletotrichum patógenas de plantas de fresa

1999

Molecular analysis of the fungal community associated with phyllosphere and carposphere of fruit crops

Transcriptome profiling of citrus fruit response to huanglongbing disease.

2010

Huanglongbing (HLB) or "citrus greening" is the most destructive citrus disease worldwide. In this work, we studied host responses of citrus to infection with Candidatus Liberibacter asiaticus (CaLas) using next-generation sequencing technologies. A deep mRNA profile was obtained from peel of healthy and HLB- affected fruit. It was followed by pathway and protein-protein network analysis and quantitative real time PCR analysis of highly regulated genes. We identified differentially regulated pathways and constructed networks that provide a deep insight into the metabolism of affected fruit. Data mining revealed that HLB enhanced transcription of genes involved in the light reactions of phot…

Botrytis cinerea strains infecting grapevine and tomato display contrasted repertoires of accessory chromosomes, transposons and small RNAs

2022

Botrytis cinerea stands out for having a wide host range and is qualified as generalist.Nevertheless, recent studies suggest that it actually corresponds to co-existing populationsthat show a certain level of host specialization, as described for the French populations T andG1, specialized on tomato and grapevine, respectively (Mercier et al., 2019, Env. Microbiol.21, 4808–21; Mercier et al., 2021 Phytopathology, 111,2355-66).What are the molecular determinants responsible for such host-specialization? PreviousIllumina sequencing data revealed genes under positive selection encoding cellulases,pectinases and enzymes involved in the oxidative stress response suggesting that theseactivities m…

A genomic reappraisal of symbiotic function in the aphid/Buchnera symbiosis: reduced transporter sets and variable membrane organisations.

2011

International audience; Buchnera aphidicola is an obligate symbiotic bacterium that sustains the physiology of aphids by complementing their exclusive phloem sap diet. In this study, we reappraised the transport function of different Buchnera strains, from the aphids Acyrthosiphon pisum, Schizaphis graminum, Baizongia pistaciae and Cinara cedri, using the re-annotation of their transmembrane proteins coupled with an exploration of their metabolic networks. Although metabolic analyses revealed high interdependencies between the host and the bacteria, we demonstrate here that transport in Buchnera is assured by low transporter diversity, when compared to free-living bacteria, being mostly bas…