9 research outputs found
The quasi-universality of nestedness in the structure of quantitative plant-parasite interactions
Understanding the relationships between host range and pathogenicity for parasites, and between the efficiency and scope of immunity for hosts are essential to implement efficient disease control strategies. In the case of plant parasites, most studies have focused on describing qualitative interactions and a variety of genetic and evolutionary models has been proposed in this context. Although plant quantitative resistance benefits from advantages in terms of durability, we presently lack models that account for quantitative interactions between plants and their parasites and the evolution of these interactions. Nestedness and modularity are important features to unravel the overall structure of host-parasite interaction matrices. Here, we analysed these two features on 32 matrices of quantitative pathogenicity trait data gathered from 15 plant-parasite pathosystems consisting of either annual or perennial plants along with fungi or oomycetes, bacteria, nematodes, insects and viruses. The performance of several nestedness and modularity algorithms was evaluated through a simulation approach, which helped interpretation of the results. We observed significant modularity in only six of the 32 matrices, with two or three modules detected. For three of these matrices, modules could be related to resistance quantitative trait loci present in the host. In contrast, we found high and significant nestedness in 30 of the 32 matrices. Nestedness was linked to other properties of plant-parasite interactions. First, pathogenicity trait values were explained in majority by a parasite strain effect and a plant accession effect, with no parasite-plant interaction term. Second, correlations between the efficiency and scope of the resistance of plant genotypes, and between the host range breadth and pathogenicity level of parasite strains were overall positive. This latter result questions the efficiency of strategies based on the deployment of several genetically-differentiated cultivars of a given crop species in the case of quantitative plant immunity
Etude des contraintes liées à la riziculture d'altitude et au développement des variétés adaptées à ces conditions. Volet phytopathologie. Rapport annuel pour la période du 1/10/1990 au 30/09/1991. Contrat CEE n. TSD 2 - 0046 B
Rapport de mission au Népal du 17 au 28 septembre 1992 : contraintes liées à la riziculture d'altitude au Népal
Cette mission avait pour but de comparer la riziculture d'altitude du Népal avec celle de Madagascar, et plus spécifiquement sur le plan des pressions phytopathologique
Concordance et dissociation des seuils de fatigue électromyographiques et des seuils ventilatoires chez le patient en réadaptation cardiaque
International audienc
Dissociation des rĂ©ponses cardiorespiratoires et neuromusculaires Ă lâexercice Ă la suite de 4 semaines de rĂ©entraĂźnement Ă lâeffort chez des patients cardiaques
International audienc
Synthesis and antitumoral activity of novel thiazolobenzotriazole, thiazoloindolo[3,2-c]quinoline and quinolinoquinoline derivatives
International audienc
Une structure emboßtée universelle pour les interactions quantitatives entre les plantes et leurs parasites ?
National audienc