Apply mancozeb or chlorothalonil to protect plants. Fusarium Yellows Roots have brown spots or general rot. Older leaves yellow. Flower size, shape and color may be abnormal. Flowers may not develop while stalks are curved in an S-shape.
Corms rot from the center outward.
Oval, sunken spots on the corm surface are brown and may have concentric rings. Fusarium oxysporum f. sp. Maintain a soil pH of 6.6-7.0 and use nitrate as the nitrogen source when fertilizing. Scab Brown spotting occurs on leaves. Brown, round, sunken areas with raised edges are on corms.