Pucciniales
Orange-brown pustules on undersides of leaves. Yellow spots on upper leaf surface. Early leaf drop.
Fusarium oxysporum
Yellowing leaves starting on one side of the plant, wilting despite moist soil, brown vascular tissue.
Aphidoidea
Clusters of small soft insects on new growth. Sticky honeydew residue. Distorted, curling leaves.
Phytophthora infestans
Dark brown lesions on leaves and stems. White mould on underside of leaves. Fruit rots rapidly.
Erysiphales
White powdery coating on leaves and stems. Leaves may curl, yellow and drop prematurely.