Canadian Forest Service Publications
Indigenous fungi as potential biological control agents for invasive Rubus spp. in Canadian forests (Abstract) 1998. Shamoun, S.F.; Oleskevich, C. Page 18 in IV International Bioherbicide Workshop - Programme and Abstracts., August 6-7, 1998, University of Strathclyde, Glasgow, Scotland. University of Strathclyde, Glasgow, Scotland.
Issued by: Pacific Forestry Centre
Catalog ID: 5074
To suppress weedy Rubus spp. which compete with young conifers in reforestation sites, a biological control strategy employing indigenous fungi is under investigation. Fungi were isolated from diseased Rubus spp. (R. strigosus, R. parviflorus and R. spectabilis) and evaluated as potential biocontrol agents in pathogenicity screening tests. A candidate fungus, Fusarium avenaceum, induced moderate to severe leaf area necrosis to Rubus plants with an inundative foliar application. Inoculum production methods, amendment of inocula with adjuvants (nutrients, humectants, surfactants), co-application with low doses of glyphosate, and other formulations have been investigated to increase pathogenicity. Foliar infection was increased significantly when F. avenaceum was grown on a rice-grain substrate, combined with an organosilicone surfactant (0.4% Silwet L-77) and applied to R. strigosus and R. parviflorus plants under shadehouse conditions. Extraction and analysis of infested rice filtrates for metabolite production indicated the presence of a single phytotoxin, moniliformin, at levels of 3,300 ppm. Further research is focused on improvement of the formulation, determining optimum application methodology, and screening of F. avenaceum phytotoxins on Rubus spp. using tissue culture techniques. The potential for further development of F. avenaceum as a microbial control agent of select Rubus spp. will be discussed.