Barley – Scald and net blotch

Crop(s):          Barley

Disease(s):     Scald and net blotch

Resistance Management Strategy for:

Group 3               Demethylation inhibitors (DMI);
Group 7               Succinate dehydrogenase inhibitors (SDHI);
Group 7 + 3        SDHI + DMI;
Group 11 + 3      Quinone outside inhibitor (QoI) + DMI;
Group 11 + 4      QoI + phenylamides (PA); and
Group 11+7+3   QoI + SDHI + DMI.

  1. Fungicides should be used as protectant treatments – where there is no more than 5% leaf area infection evident anywhere in the canopy. In high risk disease environments, integrated management approaches should be used to reduce fungicide resistance risk, which may include:
    1. removal of stubble,
    2. crop rotation (avoid barley on barley),
    3. control of green bridge volunteers; and
    4. the use of tolerant and resistant varieties.
  2. Do not apply more than one application of a Group 7 seed treatment with foliar activity in any two consecutive growing seasons.
  3. Do not apply more than two applications per growing season of Group 11 or 7 containing products. This includes foliar sprays as well as in-furrow or seed treatments that have activity on foliar diseases. Combinations of in-furrow and seed treatment are counted as one application.
  4. Do not apply consecutive applications of Group 11 containing products. This includes in-furrow i.e. if a Group 11+4 or 11+3+7 fungicide has been used in-furrow at planting, the first foliar fungicide spray must not contain a Group 11 fungicide.
  5. If a Group 7 seed treatment has been used with foliar activity (as determined by label claims), the first foliar fungicide applied should not contain a Group 7 fungicide.
  6. If a Group 7 fungicide is being applied as a foliar spray, it must be in a co-formulation or in mixture with a registered mixing partner with a different mode of action, with no known resistance.
  7. Do not apply more than three applications containing Group 3 fungicides per growing season. This total of three applications includes DMIs applied as Group 11+3 or Group 11+7+3 co-formulations and in-furrow or seed treatments that have activity on foliar diseases. Combinations of in-furrow and seed treatments are counted as one application.
  8. Minimise use of Group 3 fungicides which are known to have compromised resistance status. Where possible, alternate between different Group 3 fungicides. Maintain Group 3 applications in line with the above guidelines and the product labels.


  1. Minimise use of Group 7 fungicides with foliar activity where resistance has been confirmed.
  2. Minimise the use of Group 7 fungicides (seed treatments and foliar sprays) to high-risk crop varieties.
  3. Group 7 fungicides should not comprise more than 50% of the total number of fungicide applications targeting this disease, which includes seed treatments with foliar activity and foliar sprays per season.

Content last updated: June 30, 2022

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 30 June 2022. All previous versions of this strategy are now invalid.