Fungicide Evaluations for Control of Blackleg in Canola
Carl Bradley, North Dakota State University - $14,000
Paul Porter, University of Minnesota - $6,000

Blackleg, caused by the fungus Leptosphaeria maculans, can be a devastating disease to canola in Canada and the United States. Results from field surveys conducted by North Dakota State University personnel indicate that blackleg incidence has risen in North Dakota in recent years.

Although blackleg resistant cultivars are available to canola growers, the recent discovery of the pathogenicity group (PG) 3 strain of L. maculans in Manitoba and North Dakota which is able to cause disease on some resistant cultivars, may mean that alternative methods of management such as fungicides might be needed.

Although some fungicides have been evaluated for efficacy against blackleg, no data for new chemistry type fungicides such as the QoI and carboximide fungicides has been reported for their efficacy against blackleg on canola. These fungicides are considered low-risk by the Environmental Protection Agency and have recently been registered on a wide variety of crops (including canola). If effective and economical, these fungicide products may be used in an integrated program to manage blackleg effectively.

Objectives:
1. Evaluate fungicides previously identified as having efficacy against blackleg at different use rates on a moderately susceptible canola cultivar.
2. Evaluate Quadris fungicide at two different use rates on three cultivars differing in their levels of susceptibility and resistance to blackleg.