Search results for "patho"
showing 10 items of 10772 documents
An STE12 gene identified in the mycorrhizal fungus Glomus intraradices restores infectivity of a hemibiotrophic plant pathogen
2009
International audience; * • Mechanisms of root penetration by arbuscular mycorrhizal (AM) fungi are unknown and investigations are hampered by the lack of transformation systems for these unculturable obligate biotrophs. Early steps of host infection by hemibiotrophic fungal phytopathogens, sharing common features with those of AM fungal colonization, depend on the transcription factor STE12. * • Using degenerated primers and rapid amplification of cDNA ends, we isolated the full-length cDNA of an STE12-like gene, GintSTE, from Glomus intraradices and profiled GintSTE expression by real-time and in situ RT-PCR. GintSTE activity and function were investigated by heterologous complementation …
Gene flow and population admixture as the primary post-invasion processes in common ragweed (Ambrosia artemisiifolia) populations in France
2010
*An improved inference of the evolutionary history of invasive species may be achieved by analyzing the genetic variation and population differentiation of recently established populations and their ancestral (historical) populations. Employing this approach, we investigated the role of gene flow in the post-invasion evolution of common ragweed (Ambrosia artemisiifolia). *Using eight microsatellite loci, we compared genetic diversity and structure among nine pairs of historical and recent populations in France. Historical populations were reconstructed from herbarium specimens dated from the late 19th to early 20th century, whereas recent populations were collected within the last 5 yr. *Re…
Glutathione deficiency of the Arabidopsis mutant pad2-1 affects oxidative stress-related events, defense gene expression and hypersensitive response
2011
L'article original est publié par The American Society of Plant Biologists; International audience; The Arabidopsis (Arabidopsis thaliana) phytoalexin-deficient mutant pad2-1 displays enhanced susceptibility to a broad range of pathogens and herbivorous insects that correlates with deficiencies in the production of camalexin, indole glucosinolates, and salicylic acid (SA). The pad2-1 mutation is localized in the GLUTAMATE-CYSTEINE LIGASE (GCL) gene encoding the first enzyme of glutathione biosynthesis. While pad2-1 glutathione deficiency is not caused by a decrease in GCL transcripts, analysis of GCL protein level revealed that pad2-1 plants contained only 48% of the wild-type protein amoun…
Morphogenetic modifications induced by Pseudomonas fluorescens A6RI and Glomus mosseae BEG12 in the root system of tomato differ according to plant g…
2002
Summary • The ability of fluorescent pseudomonads and glomalean fungi to promote plant growth has been reported many times. However, little is known of their effects on root morphogenesis. Growth and root morphogenesis were compared in tomato ( Lycopersicon esculentum ) plants inoculated or not with a model strain of Pseudomonas fluorescens (A6RI) or with the arbuscular mycorrhizal fungus Glomus mosseae (BEG12). • Plants were cultivated in a sandy-loam soil mixed with sand at two different ratios (2 : 1 and 1 : 2), in gnotobiotic conditions. Plant growth was evaluated by measuring root and shoot fresh weight, and various morphometric parameters were compared. • Growth of control plants was …
Elicitor and resistance-inducing activities of -1,4 cellodextrins in grapevine, comparison with -1,3 glucans and -1,4 oligogalacturonides
2007
Cellodextrins (CD), water-soluble derivatives of cellulose composed of beta-1,4 glucoside residues, have been shown to induce a variety of defence responses in grapevine (Vitis vinifera L.) cells. The larger oligomers of CD rapidly induced transient generation of H2O2 and elevation in free cytosolic calcium, followed by a differential expression of genes encoding key enzymes of the phenylpropanoid pathway and pathogenesis-related (PR) proteins as well as stimulation of chitinase and beta-1,3 glucanase activities. Most of these defence reactions were also induced by linear beta-1,3 glucans (betaGlu) and alpha-1,4 oligogalacturonides (OGA) of different degree of polymerization (DP), but the i…
Symbiosis-related plant genes modulate molecular responses in an arbuscular mycorrhizal fungus during early root interactions.
2009
To gain further insight into the role of the plant genome in arbuscular mycorrhiza (AM) establishment, we investigated whether symbiosis-related plant genes affect fungal gene expression in germinating spores and at the appressoria stage of root interactions. Glomus intraradices genes were identified in expressed sequence tag libraries of mycorrhizal Medicago truncatula roots by in silico expression analyses. Transcripts of a subset of genes, with predicted functions in transcription, protein synthesis, primary or secondary metabolism, or of unknown function, were monitored in spores and germinating spores and during interactions with roots of wild-type or mycorrhiza-defective (Myc–) mutan…
Emergence and growth of hybrids between Brassica napus and Raphanus raphanistrum.
2003
Summary • Risk assessment studies of transgenic crops have recently brought evidence of a low spontaneous hybridization frequency of Brassica napus with Raphanus raphanistrum. The fate of the first generation hybrids is crucial to determine the initial rate of spread of transgenes. • This work aims to compare the fitness components of parents and F1 hybrids at the first step of the life cycle. The ability to emerge, establish seedling, cover the soil and develop adult plant was examined in controlled and field conditions, alone or in competition. • The F1 hybrids showed a lower seedling emergence, a significant delay of emergence, and a lower survival than for both parents. Rosette diameter…
Nuclear protein kinases: still enigmatic components in plant cell signalling
2010
International audience; Plants constantly face changing conditions in their environment. Unravelling the transduction mechanisms from signal perception at the plasma membrane level down to gene expression in the nucleus is a fascinating challenge. Protein phosphorylation, catalysed by protein kinases, is one of the major posttranslational modifications involved in the specificity, kinetic(s) and intensity of a signal transduction pathway. Although commonly assumed, the involvement of nuclear protein kinases in signal transduction is often poorly characterized. In particular, both their regulation and mode of action remain to be elucidated and may lead to the unveiling of new original mechan…
Interactions between dark septate endophytes, ectomycorrhizal fungi and root pathogens in vitro
2019
ABSTRACT Dark septate endophytes (DSEs) are widely distributed worldwide and can promote plant growth. Therefore, they are considered potentially important plant allies, especially in stressful environments. Previous studies have reported that DSEs cohabit roots with other microorganisms such as ectomycorrhizal (ECM), endophytic and pathogenic fungi/oomycetes. However, interactions between different DSE species have not yet been reported, and studies on the interactions between DSEs and other fungi are scarce. Using a simple and reproducible pairwise growth assay in vitro, we studied the synergistic/antagonistic interactions between eight DSEs, two ECM fungi and three root pathogens. Most o…
Permanent genetic resources added to molecular ecology resources database 1 April 2010 - 31 May 2010
2010
Correspondance: Molecular Ecology Resources Primer Development Consortium, E-mail: editorial.office@molecol.com; International audience; This article documents the addition of 396 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Anthocidaris crassispina, Aphis glycines, Argyrosomus regius, Astrocaryum sciophilum, Dasypus novemcinctus, Delomys sublineatus, Dermatemys mawii, Fundulus heteroclitus,Homalaspis plana, Jumellea rossii, Khaya senegalensis, Mugil cephalus, Neoceratitis cyanescens, Phalacrocorax aristotelis, Phytophthora infestans, Piper cordulatum, Pterocarpus indicus, Rana dalmatina, Rosa pulverulenta, Saxifraga …