Department of Horticulture, Rutgers University, Philip E. Marucci Center for Blueberry and Cranberry Research and Extension, Chatsworth, NJ 08019
Mummy berry disease caused by Monilinia vaccinii-corymbosi is the most widespread economically important problem of cultivated blueberry in North America. In an attempt to identify new sources of resistance to the fruit rot (mummification) phase of mummy berry, 140 accessions from a total of 21 populations from seven wild diploid species of blueberry were evaluated for resistance under greenhouse conditions. Six isolates of M. vaccinii-corymbosi from three states were used as inoculum. A highly resistant response to mummy berry fruit rot was exhibited by all accessions of Vaccinium boreale, V. myrtilloides, V. pallidum, and V. tenellum, and by most accessions of V. darrowi. Most of the V. corymbosum and V. elliottii accessions were moderately to highly susceptible. Introgression of the resistance found in the wild diploid species into horticulturally desirable cultivars could significantly improve available resistance.