"Alternaria may result in plant death"
Alternaria survives and can overwinter as spores and mycelium in infected plant residues (leaves, stems, tubers, etc.) and on or in seeds. If Alternaria spores are on or in seed, they can germinate with the seed causing damping off in seedlings. More frequently, Alternaria diseases come from plant residues that can infect young and more mature plants causing stem lesions or collar rot. During periods of rain fall, heavy dew or high moisture conditions in the soil, Alternaria will grow and sporulate outdoors or inside a greenhouse. Alternaria infections often appear as dark sunken lesions that can appear on roots, tubers, stems and fruits. Mycelium growth appears on lesions as fine, black fuzzy growth that quickly produce gray to black spores.
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