Tomato – Target spot (early blight)

Crop(s):          Tomato

Disease(s):     Target spot (early blight)

Resistance management strategy for:

Group 2 Dicarboximide;
Group 3 Demethylation Inhibitors (DMI);
Group 7 Succinate dehydrogenase inhibitors (SDHI);
Group 7+3

Group 7+11

SDHI + DMI

SDHI + Quinone outside Inhibitor (QoI)

Group 9 Anilinopyrimidine;
Group 11 QoI;
Group 11+3 QoI + DMI, and
Group 21 Quinone inside Inhibitor (QiI)

Guidelines:

  1. Apply a program of protectant fungicides from early crop establishment and maintain a regular spray program throughout the crop growing cycle.
  2. Do not apply more than four Group 2 sprays in one crop. Apply no more than two consecutive sprays of a Group 2
  3. Do not apply more than six Group 3 sprays in a crop. Apply no more than two consecutive sprays of a Group 3 fungicide alone.
  4. If applying Group 7 or 21 containing fungicides, do not apply more than two consecutive sprays before changing to another group. If consecutive sprays are used, then use the same number of sprays of an alternative group before using another Group 7 or 21, including sprays in consecutive crops.
  5. Group 7 applied solo or Group 21 should not exceed three applications or thirty-three percent (33%) of the total applications needed per crop (whichever is lower). Group 7 applied in a mixture should not be more than 50% of applications made in a crop. A maximum of five applications of Group 21 may be made per calendar year in case of multiple cropping cycles.
  6. If three or fewer fungicide sprays for target spot are applied per crop, use only one spray containing a Group 9 If four to six sprays are applied per crop, use a maximum of two sprays containing Group 9 fungicides. If seven or more sprays are applied per crop, use a maximum of three sprays containing Group 9 fungicides.
  7. Apply no more than two consecutive sprays containing a Group 9
  8. Apply Group 11 fungicides preventively. Do not apply more than six sprays, or one third of the total sprays (whichever is lower) from Group 11 Do not apply more than two consecutive sprays of Group 11 fungicides. If consecutive applications of Group 11 fungicides are used, then they must be followed by at least the same number of applications of fungicide(s) from a different group(s) before a Group 11 fungicide is used again, either in the current or following season.

URL: https://croplife.org.au/resources/programs/resistance-management/tomato-target-spot-early-blight/
Content last updated: June 26, 2024

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 www.apvma.gov.au

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 26 June 2024. All previous versions of this strategy are now invalid.