Location: Crops Pathology and Genetics ResearchTitle: Two new Cytospora species, Cytospora vinacea sp. nov. and Cytospora viticola sp. nov., from declining vineyards in eastern North America
|LAWRENCE, DANIEL - University Of California|
|TRAVADON, RENAUD - University Of California|
|POUZOULET, JEROME - University Of California|
|ROLSHAUSEN, PHILIPPE - University Of California|
|WILCOX, WAYNE - Cornell University - New York|
Submitted to: Mycological Society of America
Publication Type: Abstract Only
Publication Acceptance Date: 6/30/2016
Publication Date: 8/1/2016
Citation: Lawrence, D., Travadon, R., Pouzoulet, J., Rolshausen, P.E., Wilcox, W.F., Baumgartner, K. 2016. Two new Cytospora species, Cytospora vinacea sp. nov. and Cytospora viticola sp. nov., from declining vineyards in eastern North America. Mycological Society of America Meeting Abstracts. #148. ipmb.berkeley.edu/sites/default/files/MSA%202016%20abstracts%20and%20index.pdf.
Technical Abstract: Cytospora species are ubiquitous pathogens of woody plants, causing branch dieback and wood cankers in numerous perennial hosts, including agronomic crops (e.g., Prunus), timber trees (e.g., Eucalyptus), and riparian hosts (e.g., Salix). Cytospora chrysosperma, C. cincta, and C. leucostoma have been reported from grapevines showing symptoms of one or more grapevine trunk diseases (Esca, Botryosphaeria dieback, Eutypa dieback, and Phomopsis dieback), none of which are known to be caused by or associated with Cytospora species, but instead by other ascomycetes (Phaeomoniella chlamydospora and Phaeoacremonium minimum, Neofusicoccum parvum, Eutypa lata, and Diaporthe ampelina, respectively). To understand the role of Cytospora in the grapevine trunk-disease complex, 21 Cytospora isolates were identified from symptomatic vines of Vitis vinifera or Vitis hybrids, from vineyards in seven states and two Canadian provinces in eastern North America. Phylogenetic analyses of ITS, translation elongation factor 1-a, and beta-tubulin nuclear regions revealed two new species: Cytospora vinacea sp. nov. and Cytospora viticola sp. nov. Both species were pathogenic when inoculated to the woody stems of potted V. vinifera ‘Thompson Seedless’ in the greenhouse, based on development of wood lesions and fulfillment of Koch’s postulates. Cytospora viticola was more virulent, producing the largest lesions (mean lesion length =17.3 mm at 12 months post-inoculation). Morphological comparisons of the two species revealed they are clearly distinguishable, based on cultural and conidial dimensions. This study represents the first attempt to characterize pathogenic Cytospora species associated with grapevine trunk diseases in eastern North America.