Grape – Downy Mildew

Crop(s): Grape

Pest(s): Downy Mildew

Resistance Management Strategy for:

Group 4            (Phenylamide);

Group 11          (Quinone outside Inhibitor);

Group 21          (Quinone inside Inhibitor);

Group 40          (Carboxylic acid amide); and

Group 45          (Quinone outside inhibitor, stigmatellin binding type) fungicides

1. Apply all these fungicides preventatively, Group 4 fungicides should be applied before the first sign of oilspots or as soon as possible after an infection period.
2. Mixtures – co-formulations or tank mixes with label rate of alternative mode of action
3. Apply a maximum of two consecutive applications of any one group.
4. Start preventative disease control sprays using non-Group 4 protectant fungicides, typically when shoots are 10-20cm long. Continue spraying at intervals of 7-21 days depending on disease pressure, label directions and rate of vine growth.
5. Limit the use of Group 4 fungicides to periods when conditions favour disease development. Always apply Group 4 fungicides in mixtures.

6. Group 40 – do not apply as the last spray of the season.

Group 40 – apply a maximum of 50% of the total number of downy sprays.

7. Group 11 – If applied alone, do not make consecutive applications.

8. Group 11 – apply a maximum of 2 sprays per season, including mixtures.