ARS | Publication request: Ranking cultivated blueberry for Mummy Berry Blight and Fruit Infection Incidence

Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 19, 2010
Publication Date: July 1, 2010
Citation: Ehlenfeldt, M.K., Polashock, J.J., Stretch, A., Kramer, M.H. 2010. Ranking cultivated blueberry for Mummy Berry Blight and Fruit Infection Incidence. HortScience. 45:1205-1210.

Interpretive Summary: Mummy berry is an important disease of cultivated blueberry and the USDA has done considerable work screening blueberry varieties to identify sources of resistance to mummy berry. In this study we screened blueberry varieties for resistance to both phases of this disease and ranked these varieties against ‘standards’ of known susceptibility. Among the varieties tested, lowbush and half-high types, in general, appeared to be less susceptible to both blight and fruit infection than did either highbush or rabbiteye blueberry varieties. Among highbush varieties, ‘Bluejay’, which has been used as a standard for long-term evaluations, stood out as being among the best for resistance to both phases of mummy berry. This information will allow growers, extension agents, and researchers to more effectively evaluate varieties and predict plant responses to both phases of this disease.

Technical Abstract: Mummy berry is an important disease of cultivated blueberry. The disease has two distinct phases; a blighting phase initiated by ascospores and a fruit infection stage initiated by conidia. In this study we investigated the resistance of more than 100 blueberry cultivar to both phases of the disease utilizing ‘standards’ of known susceptibility. By utilizing standards, tested cultivars were conservatively ranked for resistance to both phases of the disease. Among the cultivars tested, lowbush and half-high types, in general, appeared to be less susceptible to both blight and fruit infection than did either highbush or rabbiteye blueberry cultivars. Among highbush cultivars, ‘Bluejay’, which has been used as a standard for long-term evaluations, stood out as being among the best for resistance to both phases of mummy berry. This information will allow growers, extension agents, and researchers to more effectively evaluate cultivars and predict cultivar responses to both phases of this disease.