Early blight
How to prevent Early blight Remove crop residues, weeds and volunteer plants. Use clean seed and propagation materials. Practice crop rotation, in particular [...] conducive to infection. In greenhouses: avoid high RH. Prevent plant diseases by optimizing plant potential and crop resilience. [...] infection of the leaves. Survival can be several years, up to eight years for several Alternaria spp. Typically, Alternaria causes early blight of potato