Canola – Blackleg and Sclerotinia

Crop(s):          Canola

Disease(s):     Blackleg and Sclerotinia

Resistance Management Strategy for:

Group 2               Dicarboxamides;
Group 3               Demethylation inhibitors (DMI);
Group 7               Succinate dehydrogenase inhibitors (SDHI);
Group 7+3          SDHI + DMI; and
Group 7+12         SDHI + phenylpyrroles (PP); and
Group 11+3        Quinone outside inhibitors (QoI) + DMI

1. Fungicides should be used primarily as a preventative or at first sign of disease. If disease is established within the canopy, fungicides may not produce optimal results and there is very strong potential to select for fungicide resistance. Sclerotinia targeted applications should be applied during flowering of the crop, prior to an infection period. Applications of fungicides for Sclerotinia may put selection pressure on the blackleg population.
2. In high risk disease environments, integrated management approaches should be used to reduce fungicide resistance risk including growing canola at least 500 m from previous seasons canola stubble, the use of resistant varieties, using alternative fungicide modes of action and stubble management such as knocking down and/or strategic burning.
3. The risk of developing resistance to fungicides can be reduced by incorporating different modes of action into blackleg management programs as either mixtures, co-formulations or rotations.
4. If a Group 7 seed treatment has been used with foliar activity on blackleg (as determined by label claims), the seedling fungicide application at 4-6 leaf stage targeting blackleg should not contain a Group 7 fungicide.
5. Do not apply more than two applications containing Group 7 fungicides per growing season. Combinations of in furrow and seed treatment are counted as one application.
6. Do not apply more than two consecutive applications of a Group 3 fungicide.
7. Do not apply more than one application containing a Group 11 fungicide.
8. Minimise use of fungicides which are known to have compromised resistance status.
9. If seasonal conditions require a second fungicide application at 50% flowering after a 20% flowering timing, the second application should be from a different Group.

If a second application at 50% flowering is required: