Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/15/2007
Publication Date: 8/1/2007
Citation: Bruckart, W.L., Mcclay, A., Hambleton, S., Tropiano, R., Hill-Rackette, G. 2007. First Report of Puccinia lagenophorae on Common Groundsel (Senecio vulgaris) in Canada. Plant Disease. 91:1058-1058.
Interpretive Summary: The weed, common groundsel, can become diseased and be damaged or killed if it is infected by a fungus called Puccinia lagenophorae. Earlier, studies were conducted to use this fungus to kill the weed, but then it was found in the United States. Now it has been found for the first time in Canada. In September, 2005, it was discovered near Edmonton, in Alberta. Identification of the fungus as P. lagenophorae was made because it is similar to the fungus found in the United States and in Europe. Specimens have been deposited in two herbaria and other information has been put into a database. Finding this fungus in new places in the United States and Canada is important, because we want to know if it kills the weed. However, there are many other plants like groundsel in the United States and Canada. For this reason, it is important to follow spread of P. lagenophorae to see if it also will infect and damage these closely related plants.
Technical Abstract: Puccinia lagenophorae, a rust fungus from Europe and Australia, has been studied for biological control of Common groundsel (Senecio vulgaris) in North America. It has since been found in the United States (California, Oklahoma, and on the East Coast). In September, 2005, it was found in two locations near Edmonton, Alberta, Canada. Based on host plant and both morphological and molecular characteristics, the pathogen was identified as P. lagenophorae. Ambiguities were found in the ITS1 spacer region at position 7 and after position 130. Similar variation has been reported in another study. Clones of Canadian sequences matched one from the United Kingdom and one from the United States (GenBank Nos. AY808060 and AY852264, respectively). Telia and teliospores were not observed in any of the samples from 2005 (some collected as late as November) or 2006 (only at the Edmonton site). The original source of inoculum for these infections is unknown, but diseased specimens with sporulating aecia were found beneath 45 cm of snow at the Edmonton location. Specimens have been deposited at the Arthur Herbarium, Purdue University, West Lafayette, IN and at the National Mycological Herbarium of Canada, Ottawa, ON. Sequences of the two ITS variants were deposited in GenBank (Acc. Nos. EF212446 and EF212447). This is the first report of groundsel rust caused by P. lagenophorae in Canada. Groundsel rust has been found at several locations in the U.S., and has been reported on more than 60 species in several genera. Questions remain about the amount of damage P. lagenophorae will cause to groundsel in North America and whether it will affect other related species, including numerous native representatives of the genus Senecio.