Wheat – Septoria blotch

Crop(s):          Wheat

Disease(s):     Septoria blotch

Resistance Management Strategy for:

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

  1. Fungicides should be used as protectant treatments – prior to symptoms of disease when conditions are conducive to disease development.
  2. In high risk environments, integrated management approaches should be used to reduce fungicide resistance risk, which may include:
    • removal or burning of stubble,
    • crop rotation (avoid wheat on wheat),
    • control of green bridge volunteers; and
    • use of tolerant and resistant varieties.
  3. Do not apply more than one application of a Group 7 seed treatment with foliar activity in any two consecutive growing seasons.
  4. Do not apply more than two applications per growing season of Group 11 or 7 containing products. Foliar sprays and in-furrow or seed treatments that have activity on foliar diseases, count towards total. Combinations of in-furrow and seed treatment are counted as one application.
  5. If a Group 7 seed treatment has been used with foliar activity (as determined by label claims), the first foliar fungicide applied must not contain a Group 7 fungicide. An alternative mode of action fungicide should be applied at typical foliar fungicide timing.
  6. If a Group 7 or 11 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. The mixture partner should also provide effective disease control when used alone on the target disease.
  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 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.
  9. Reduced rates, including with multiple applications, must not be used. Always used labelled rates.
  10. Apply Group 21 preventatively, using a maximum of one Group 21 spray per crop. Do not apply Group 21 solo, they must be applied in combination with an effective tank mix partner from a different group.

URL: https://croplife.org.au/resources/programs/resistance-management/wheat-septoria-blotch/
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 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 14 July 2023. All previous versions of this strategy are now invalid.