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FIG.01 — Powdery mildew, diseaseTap to enlarge
Plant part
Leaf
P. persimilis
AVOID / RESTRICTED
DiseaseProblem 07 / 32
Powdery mildew
Symptoms
White powdery growth on leaf surfaces; leaves yellow, curl, dry, and lose vigor.
How to verify
Compare the photos above with the plant, and check the symptom description against the look-alike records below before acting. The source guide does not carry a separate laboratory verification note for this record.
Next step
Improve ventilation and avoid excessive nitrogen. Remove severely affected leaves. Use a labeled sulfur, potassium bicarbonate, or registered fungicide such as azoxystrobin, observing crop-safety restrictions and avoiding sulfur in excessive heat.
Active ingredients
penconazoletriadimenoltetraconazoletetraconazole + sulphurdifenoconazoletebuconazolecyproconazolemyclobutanilsulphurtea tree oilpotassium bicarbonatemetrafenonefluopyram + tebuconazolefluopyram + trifloxystrobintrifloxystrobinazoxystrobinbacillus subtilispyriofenone
Organic active ingredients
sulfurcalcium polysulfidehydrogen peroxide
P. persimilis: allowed / avoid
PERSIMILIS STATUS: AVOID / RESTRICTED. Sulfur dusting can harm beneficials; do not use during an active Phytoseiulus persimilis program unless the supplier confirms compatibility.
Label matters
Active ingredients below are examples, not universal prescriptions. Confirm the diagnosis; use only products registered for tomato and the target problem in your country; and follow the current label for dose, pre-harvest interval, worker protection, compatibility and re-entry. Rotate IRAC/FRAC modes of action. When symptoms are uncertain, obtain a laboratory or extension diagnosis. Integrated pest management (IPM)—sanitation, resistant varieties, irrigation management, monitoring and biological control—should be the first line of defense.
Look-alikes to rule out
