When available, it is also helpful to use resistant varieties. Chemical controls are not effective for these fungi. Root and crown rots, Rhizoctonia solani, Pythium. This general droopiness or flaccid appearance is often accompanied by browning and rotting of the roots and the crown. Yellowing and death of the outer leaves follows, until finally the entire plant is dead.
Control can be difficult once plants are infected so prevention is important.
It is helpful to avoid overwatering, especially in heavy soils, and to avoid watering directly into the crown area of the plant. Highly symptomatic plants can be rogued and removed since recovery is unlikely. Leaf spots, Septoria, Alternaria. Pale tan to brown spots with purple borders appear on leaves. These can vary in color, size, and number.