Exploring the prevalence of esca-induced leaf symptoms in French vineyards and the role of climate: a national scale analysis
Esca, a severe trunk disease affecting vineyards, is caused by fungal pathogens that induce wood necrosis and decay, leaf symptoms, yield losses, and potentially a rapid death of the vine. The prevalence of this disease varies across years, regions, cultivars, and plot ages. Despite its significance in understanding and predicting dieback risk in different vineyards, the role of climate in trunk diseases remains a relatively unexplored research area. While some studies have demonstrated the impact of certain climatic conditions on the prevalence of the disease, they often focus on a limited number of plots and yield conflicting results.We conducted a statistical analysis, using a Bayesian approach on a national database comprising prevalence data of esca from over 500 different plots in France, spanning the years 2003 to 2022 and encompassing various cultivars. The aim was to identify the climatic risk factors while considering plot-specific factors such as cultivar and age. Climate factors as soil moisture and temperature were assessed with the French climate database SAFRAN.
The results revealed a non-linear relationship between age and esca prevalence, which was dependent on the cultivar. Specifically, we observed that prevalence tends to increase between the ages of 15 and 40 years, varying with the cultivar, and subsequently declined gradually. Furthermore, significant effects were found, particularly indicating an increase in esca prevalence with higher soil moisture levels. Conversely, an increase in average air temperature tends to decrease the prevalence of esca in the field. These results highlighted the importance of climatic factors on esca prevalence.
Acknowledgements: We would thank the Plan National Dépérissement du Vignoble for funding this research. We would thank all the technical partners throughout France who gave us access to their data.
Issue: ICGWS 2023
1 INRAE, ISVV, Bordeaux Sciences Agro, Santé et Agroécologie du Vignoble, 33140 Villenave d’Ornon, France
2 INRAE, Biostatistiques et Processus Spatiaux, 84000 Avignon, France
3 INRAE, Plateforme ESV, Biostatistiques et Processus Spatiaux, 84914 Avignon, France
4 CNRS, Université Rennes 2, Littoral Environnement Télédétection Géomatique, 35045 Rennes, France