Evaluation of pest control products including biofungicides for control of clubroot on canola and cruciferous vegetables

Project Code SCR08-030

Project Lead

Gary Peng - Agriculture and Agri-Food Canada

Objective

Assess the potential of selected fungicide/biofungicide products for clubroot control on canola and cruciferous vegetable crops

Summary of Results

Background

Clubroot caused by Plasmodiophora brassicae is a serious problem on cruciferous vegetable crops and a threat to the canola industry in Canada. There is a lack of effective control options for clubroot. The project aims to assess the potential and efficacy of biopesticides which are currently registered in Canada for control of clubroot in canola and cruciferous vegetables. The end goal is to provide Canadian growers tools for the effective control of clubroot.

Approaches

Trials were conducted in 2009 in Alberta and Saskatchewan. The biofungicides Serenade, Pre-stop, Mycostop, Actinovate, and Root Shield were tested for their ability to control clubroot on canola and crucifer vegetables in growth cabinet and greenhouses. SoilGard and Taegro, two additional biofungicides registered in the United States were tested on canola in a containment facility in Saskatoon. All biofungicides were initially applied as a soil drench at 5 times label rate to soil-less growth media inoculated with P. brassicae resting spores or to pathogen-infested field soils. The conventional fungicides Allegro and Ranman applied at one times label rate were also evaluated in the trials. Selected products were further evaluated at varying concentrations, soil drench volumes, and for potential as seed treatments.

Results

Results of trials indicated that Serenade, Pre-stop, Allegro and Ranman applied as a soil-drench treatment reduced clubroot severity on canola by 85–100%. Disease pressure varied from moderate to high.

Biofungicide concentration appeared important to efficacy while soil-drench volumes may be further reduced from the current level of 25 millilitres per plant. In general all products did not perform as well in naturally infested field soils as in those trials involving inoculated growth media. This may be related to treatment application timing. Results from seed-treatment trials were too variable to draw conclusions but there was a strong indication that this approach may be successful although additional work would be required on development of microbial formulations.

Date modified: