Tomato – Powdery mildew

Crop(s):        Tomato

Disease(s):   Powdery mildew

Resistance Management Strategy for:

Group 3                     Demethylation inhibitors (DMI);
Group 11 + 3            Quinone outside inhibitors (QoI) + DMI;
Group 7                     Succinate dehydrogenase inhibitors (SDHI);
Group 7+3               SDHI + DMI;
Group 13                   Aza-napthalenes; and
Group 21                  Quinone inside Inhibitor (QiI).

  1. Apply fungicides before disease becomes established.
  2. Do not apply more than four sprays of a Group 3 containing fungicide per crop.
  3. If applying a Group 7, 11, 13 or 21 containing fungicides, do not apply more than two consecutive sprays before changing to another group. Do not apply more than three applications containing a Group 7, 11, 13 or 21 fungicide per crop. If consecutive sprays are used, then use the same number of sprays of an alternative group before using another fungicide group, which includes sprays from consecutive crops.
  4. Apply Group 21 as a protectant spray only.
    • Do no apply more than two consecutive sprays or more than three times per crop season or cropping cycle with maximum of five (5) applications per calendar year in case of multiple cropping cycles.
    • Exposure to Picolinamide (or any other Group 21 containing product) should not exceed thirty-three percent (33%) of the total period of protection needed per crop.
    • Picolinamide applications are to be made preventatively and no more than two (2) times in sequence before applying a fungicide with a different mode of action.
    • Continue alternation of fungicides between successive crops. There will be no more than five (5) applications of Picolinamide (or any other Group 21 containing product) per year on the same area.

Content last updated: July 14, 2023

CropLife Australia’s Resistance Management Strategies provide a guide for crop protection product rotation through product groups. The strategies are a useful tool that supports farmers’ adoption of resistance management. All crop protection products must be handled and applied strictly as specified on the product label or APVMA permits.

These Resistance Management Strategies do not replace product labels. They are a guide only and do not endorse particular products, groups of products or cultural methods in terms of their performance. It is important to check with the Australian regulator’s (APVMA) product database for contemporary information on products and active constituents. The database can be sourced through

The information given in this strategy is provided in good faith and without any liability for loss or damage suffered as a result of its application and use. Advice given in this strategy is valid as at 14 July 2023. All previous versions of this strategy are now invalid.