Location: Crops Pathology and Genetics ResearchTitle: Influence of Pruning Systems on Trunk Pathogens and Other Fungi Colonizing Grapevine Wood
|Travadon, R. - UNIVERSITY OF CALIFORNIA|
|Lecomte, P. - UNIVERSITY OF BORDEAUX|
|Diarra, P. - UNIVERSITY OF BORDEAUX|
|Lawrence, D.p. - UNIVERSITY OF CALIFORNIA|
|Vallance, J. - BORDEAUX AGRO SCIENCES|
|Ojeda, H. - INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE (INRA)|
|Rey, P. - BORDEAUX AGRO SCIENCES|
Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 5/15/2015
Publication Date: 11/1/2015
Citation: Travadon, R., Lecomte, P., Diarra, P., Lawrence, D., Vallance, J., Ojeda, H., Rey, P., Baumgartner, K. 2015. Influence of pruning systems on trunk pathogens and other fungi colonizing grapevine wood. American Phytopathological Society Abstracts. 68-O.
Technical Abstract: The main infection courts for fungal grapevine trunk pathogens are pruning wounds. Disease control typically involves modifications to pruning. Pruning practices requiring fewer/smaller wounds may thus be associated with fewer trunk pathogens and less wood necroses. We examined wood-colonizing fungi in the trunks of asymptomatic, 14-year-old vines (Vitis vinifera ‘Mourvèdre’ at site A, ‘Syrah’ at site B), either spur-pruned or minimally (min-) pruned. At each site, the trunks of eight min-pruned and eight spur-pruned vines were characterized in terms of necrotic wood and the community structure of the 88 cultivable fungal taxa identified through ITS sequencing. Spur-pruned vines had more wood necroses (35% vs. 20% in min-pruned vines) and a greater diversity of taxa, but not a greater abundance of trunk pathogens. Instead, Canonical Correspondence Analysis revealed different trunk pathogens: Diaporthe ampelina and Togninia minima were associated with spur pruning, and D. foeniculina, Neofusicoccum parvum, and Phaeomoniella chlamydospora with min-pruning. Among the 15 most abundant taxa, eight were more common in spur-pruned vines (e.g., wood endophytes Aureobasidium pullulans, Bionectria ochroleuca), compared to only five in min-pruned vines (e.g., Paraconiothyrium brasiliense, Pestalotiopsis microspora). Spur-pruned vines were associated with more plant pathogenic taxa, which may contribute to greater levels of wood necrosis. Both sites were affected by esca disease: out of 74 vines surveyed per cultivar, percentages of wood and leaf symptomatic vines of Mourvèdre were 32% and 12% for spur-pruned vines and min-pruned vines respectively, those of Syrah were 46% and 16% for spur-pruned vines and min-pruned vines respectively.