Occurrence, Identification, and distribution of fungal pathogens occurring on grapevine cankers in California

• Published in: Phytopathology Vol. 96; no. 6; p. S117
• Main Authors: Urbez-Torres, J R, Leavitt, G M, Gubler, W D
• Format: Journal Article
• Language: English
• Published: 01.06.2006
• Subjects: Botryosphaeria rhodina; Diplodia; Eutypa lata; Phomopsis viticola; Vitaceae
• ISSN: 0031-949X

Grapevine cankers cause millions of dollars in economic losses to the wine, table and raisin industry in California. To date, Eutypa lata and Botryosphaeria rhodina have been considered the main canker causing agents on grapevines in California, causing Eutypa dieback and Bot canker disease, respectively. In order to evaluate the occurrence of fungal pathogens associated with cankers, a field collection of perennial cankers was conducted throughout the major grape-growing areas of California. Botryosphaeria was the most abundant fungal genus isolated from grapevine cankers in California, followed by E. lata and Phomopsis viticola. Morphological identification along with DNA analysis identified 9 different Botryosphaeria species occurring on grapevines in California, including B. rhodina, B. obtusa, B. stevensii, B. australis, B. parva, B. lutea, B. dothidea, Diplodia sp. and Diplodia sarmentorum. Pathogenicity of the 9 Botryosphaeria species has been demonstrated but virulence differs by species. These findings show Botryosphaeria spp. to be a more important cause of grapevine dieback in California than previously recognized.