First Report of Puccinia coronata var. coronata sensu stricto Infecting Alder Buckthorn in the United States

Field symptoms, host distribution, pathogen morphology, and phylogenetic analyses clearly demonstrated that the rust fungus infecting alder buckthorn in Connecticut is Puccinia coronata var. coronata sensu stricto. To our knowledge, this is the first report and confirmation of P. coronata var. coronata s.s. in the United States. Additional collections from purported aecial and telial hosts of P. coronata var. coronata s.s. are necessary to determine its host range, geographic distribution, and incidence within the United States and elsewhere in North America.