Black-rot : vers une methode de prevision de risques (resume des resultats de cinq annees d'etudes)

International audienc

Influence de la date de contamination au vignoble sur l'evolution de la maturation des peritheces de Guignardia bidwellii

International audienc

Le cyproconazole : un IBS aux proprietes anti-mildiou inattendues en viticulture

National audienc

Powdery mildew on grapevine : the date primary contamination affects disease development on leaves and damage on grape

International audienc

Highlighting features of spatiotemporal spread of powdery mildew epidemics in the vineyard using statistical modeling on field experimental data

International audienceA greater understanding of the development of powdery mildew epidemics on vines would improve disease management by making assessments of the risk of invasion more accurate. We characterized the spatiotemporal spread of epidemics in the vineyard, quantified their variability, and identified the factors responsible for it. We described changes in the probability of infection of a leaf in a plot over time and as a function of distance from a source of disease. Logistic models were fitted to field data from artificially inoculated plots. The velocity of spread decreased along the row and increased in the direction of the prevailing winds. The rate of progression over time was plot dependent, and the velocity was dependent on the vigor of the vine (0.1 to 0.27 m day–1 in areas of moderate vigor and 1.1 m day–1 in areas of high vigor). When applied to a larger plot with natural primary foci, the spatiotemporal logistic model showed that the velocity and the slope of the gradient in space depended on the foci; however, the velocity remained in the same range. During the period of highest susceptibility for grape, the probability of a leaf becoming infected increased from 2.5 to 13%. Our logistic model was able to predict changes in disease over time of its extension within the plot; however, the crop heterogeneity prevented prediction of variability of disease at the vine scale

Premier cas de resistance de l'oidium a un traitement fongicide

National audienc

Sensibilite des grappes au black-rot : effet de l'interaction temperature-duree d'humectation sur la gravite de l'infection en conditions controlees

International audienc

Infestation artificielle de la vigne par l'oïdium. Des outils pour les expérimentations au vignoble

National audienc