Dogwood anthracnose: the story continues
Dogwood anthracnose caused by Discula destructiva Redlin was first detected infecting two species of dogwood on the west and east coasts of the United States (USA) in the mid-1970s. Since then, it has spread to most regions where Cornus nuttallii Audubon ex Torr. & A. Gray (pacific dogwood) grows on the west coast, and infected many C. florida L. (eastern flowering dogwood) trees in the northeast and along the Appalachian Mountains and adjacent highlands on the east coast. The disease has decimated populations of both species. A study in 1995 that used arbitrary DNA primers indicated that D. destructiva was most likely an introduced pathogen of unknown origin and had very little variability among isolates obtained from any location in the USA. Subsequent studies indicated that genetic differences existed among isolates from various regions and different years. Our current study of genetic diversity and population analyses were completed using simple sequence repeats (SSRs) to evaluate almost 100 isolates of the pathogen. Our preliminary evaluations imply that the fungus has little genetic diversity and can be categorized into several population groups. Our data supports the hypothesis that D. destructiva is an introduced pathogen.
Trigiano, R.N., Hadziabdic, D., Mantooth, K., Windham, M.T., Ownley, B.H., Staton, M.E., Miller, S. and Zhang, N. (2018). Dogwood anthracnose: the story continues. Acta Hortic. 1191, 77-82
Cornus florida, Cornus kousa, Cornus nuttallii, Discula destructiva, genetic diversity, population genetics