Phragmidium violaceum on Rubus armeniacus and R. laciniatus in British Columbia.

Abstract

Phragmidium violaceum , an introduced pathogenic rust fungus causing leaf spots and blight is reported for the first time in British Columbia from locations on central and south central Vancouver Island and the lower mainland near Aldergrove. Its hosts are two invasive introduced weed species: Rubus armeniacus , Himalayan blackberry, and R. laciniatus , evergreen blackberry. The identification of the rust was confirmed by both morphological observations and molecular techniques, and the current known distribution of the pathogen in BC is described.