Submitted to: Proceedings of Northeastern Weed Science Society
Publication Type: Abstract Only
Publication Acceptance Date: 1/1/2003
Publication Date: 1/1/2003
Citation: BRUCKART, W.L. ISSUES OF PUCCINIA LAGENOPHORAE AND BIOLOGICAL CONTROL OF COMMON GROUNDSEL IN THE UNITED STATES. PROCEEDINGS OF NORTHEASTERN WEED SCIENCE SOCIETY. 57:164. 2003.
Technical Abstract: Common groundsel (Senecio vulgaris) has been the target of the biological control approach. Recently, the rust fungus, Puccinia lagenophorae, was acquired from the U.K., because it has played a significant role in reductions of S. vulgaris populations in Europe. Under containment greenhouse conditions, the rust fungus was very aggressive, causing reductions in plant biomass. In two experiments, dry weights of inoculated plants were less than controls by 29.0 and 30.5%. Research in Europe and Australia indicate P. lagenophorae is not limited to S. vulgaris; susceptibility of English daisy (iBellis perennis), pot marigold (Calendula officinalis), and at least two other species of Senecio has been noted [1 ]. A limited host range determination in the present study showed that English daisy also could be infected but not damaged by the British acquisition of P. lagenophorae. Pot marigold was not infected in these tests. No other plant has been tested, including any of the nearly 100 species of Senecio native to North America. Recently P. lagenophorae was discovered on S. vulgaris in the United States . The fungus also has been discovered on English daisy . Issues with the discovery of P. lagenophorae in the United States include: 1) how much damage will the disease cause to common groundsel, and 2) will it cause reduction in stand density throughout the range of common groundsel in North America? An issue of greater concern and for which there is no data concerns susceptibility of North American species of Senecio and plants in related genera. Because the rust disease has been so effective in Europe and the pathogen can spread very quickly, it is of great interest to: 1) document the current distribution of infected S. vulgaris, 2) follow spread of the pathogen through the U.S., 3) document damage caused by P. lagenophorae to S. vulgrais in the field, and 4) determine if other species of native Senecio spp. and related Asteraceae are susceptible and damaged by infection. This is an appeal for help to document either the fact or the lack of infection of S. vulgaris by P. lagenophorae in the Northeast. If common groundsel is not infected, it should be documented so a clear time that the rust fungus arrives can be established. This is an invitation for anyone concerned or knowledgeable about common groundsel to participate in this process over the next few seasons. Participants are asked to record either: 1) the presence or lack of rust on common groundsel in the Northeast, or 2) the arrival of the rust in the Northeast. Samples of infected plants can be sent to me at the address above to confirm whether the infection is caused by P. lagenophorae.