Gary W. Moorman, Professor of Plant Pathology
|PHYTOPHTHORA ROOT AND CROWN ROT||Crowns and roots have dark brown spots at the soil level. This spreads up the stem and plants wilts and die. Roots are killed.||Phytophthora||Plant in pasteurized potting mix. Discard infected plants.|
|POWDERY MILDEW||Tan, scabby spots form on leaves. These may become covered with white fungal growth or remain scabby.||Sphaerotheca humili||Apply a fungicide to protect plants.|
|VIRUS||Leaves may be mottled, and have yellow spotting, dead flecks, line or ringspot patterns. Plants may be stunted and not flower.||Top spotting virus||Plant virus-indexed cuttings. Maintain good insect and mite control. Destroy infected plants. Do not take cuttings from infected plants.|
Scabby, powdery mildew symptoms (top) and white fungal growth (bottom).
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