Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract only
Publication Acceptance Date: 5/1/2005
Publication Date: 6/1/2005
Citation: Li, Y.H., Windham, M.T., Trigiano, R.N., Fare, D.C., Spiers, J.M., Copes, W.E. 2005. Components of resistance to powdery mildew in flowering dowgood. American Phytopathological Society Annual Meeting 95:S60. Interpretive Summary:
Technical Abstract: Differences in resistance to powdery mildew were observed on detached leaf disks of six flowering dogwood lines inoculated with conidia of Erysiphe pulchra. Significant differences (P < 0.02) in germinated conidia with branched hyphae, infection efficiency, latent period and sporulation were detected among lines. However, differences in percentages of spore germination (P = 0.0745) and secondary appressorium formation (P = 0.2661) were not significant among dogwood lines. In addition to sporulation, infection efficiency and latent period were major differentiable components between highly susceptible and moderately susceptible lines and between moderately susceptible and resistant lines, respectively. Similar to infection efficiency, percentages of germinated conidia with branched hyphae on highly susceptible lines were significantly greater than on resistant and moderately susceptible lines. The recently released flowering dogwood cultivar, ‘Karen’s Appalachian Blush’, expressed significantly higher levels of resistance to powdery mildew than did ‘Cherokee Brave’ in latent period and sporulation. Laboratory assays using detached leaf disks could be useful for screening dogwood selections and cultivars for resistance to powdery mildew.