Ministry of Agriculture and Lands
Stone Fruit Fungicides - Resistance Management
Updated November, 2009
The following table lists fungicides registered for use on stone fruit in British Columbia for brown rot and/or powdery mildew, categorized by resistance group.
Products in the same group have similar or identical modes of action. Over-use of products in one class of compounds will lead to resistance problems. See recommendations below for resistance management. Also check market requirements for each fungicide when considering which product to use.
| Fungicide |
Group* |
Class | Crops | Disease Spectrum | Risk of Resistance |
| Nova (myclobutanil) | 3 | DMI Fungicides - Triazoles | cherry, peach, nectarine | brown rot, powdery mildew | Medium. Resistance developing (powdery mildews) |
| Indar (fenbuconazole) | 3 | DMI Fungicides - Triazoles | all stone fruit | brown rot, powdery mildew | |
| Topas (propiconazole) | 3 | DMI Fungicides - Triazoles | all stone fruit | brown rot, powdery mildew | |
| Mission (propiconazole) | 3 | DMI Fungicides - Triazoles | all stone fruit | brown rot, powdery mildew | |
| Funginex (triforine) | 3 | DMI Fungicides - Piperazines | peach, cherry, prune/plum | brown rot, powdery mildew | medium |
| Flint (trifloxystrobin) | 11 | QoI Fungicides | cherry | powdery mildew | High |
| Cabrio (pyraclostrobin) | 11 | QoI Fungicides | all stone fruit | powdery mildew (cherry), suppression of brown rot | |
| Pristine (pyraclostrobin + boscalid) | 11 + 7 | QoI Fungicides + Pyridine carboxamides | all stone fruit | Brown rot, rhizopus rot, powdery mildew | High (pyraclsotrobin); Medium (boscalid) |
| Vangard (cyprodinil) | 9 | Anilinopyrimidine | apricot, peach, nectarine, prune/plum | brown rot, botrytis | Medium |
| Lance (boscalid) | 7 | Pyridine carboxamides | all stone fruit | brown rot, botrytis | Medium |
| Elevate (fenhexamid) | 17 | Hydroxyanilide | cherry, peach, nectarine | brown rot, botrytis | Low to Medium |
| Rovral (iprodione) | 2 | Dicarboximide | apricot, cherry, peach, plum/prune | brown rot, botrytis | Medium to High |
| Senator (thiophanate-methyl) | 1 | Benzimidazole | cherry, peach, nectarine, prune/plum | brown rot, powdery mildew | High. Some resistance to Botrytis present. |
| Captan/Maestro | M4 | Phthalimide | all stone fruit | brown rot | Low |
| Bravo (chlorothalonil) | M5 | Chloronitrile | cherry, peach, nectarine | brown rot, peach leaf curl | Low |
| Kumulus (sulphur) | M1 | Inorganic | cherry, peach, prune/plum | powdery mildew | Low |
| MilStop (potassium bicarbonate) | NC | Diverse | apricot, peach, nectarine, prune/plum | powdery mildew (suppression) | Low |
| Serenade Max | NC | Biologicals | all stone fruit | brown rot blossom blight (suppression) | Low |
*M = multi-site inhibitor; NC = not classified
Fungicide Resistance Management
Fungicide resistance management is important to prolong the effectiveness of "at risk" fungicides and to limit crop losses should resistance occur.
To help prevent resistance from developing:
- Alternate between different fungicide groups. Do not use more than 2 back-to-back sprays of fungicides with the same group number. In particular, use products rated with a medium to high risk carefully, and limit the number of applications. Products with a low risk of resistance can generally be used more often.
- Use recommended tank mixes.
- Use only recommended dose rates.
- Ensure sprayer is properly calibrated to deliver accurate and thorough coverage.
- Integrate with non-chemical control methods.
- Discontinue use of a product if resistance is suspected and consult your crop advisor.
