A disease of germinating seedlings. The term is sometimes applied to post-emergence * damping-off but generally it is used when well established seedlings are affected. Growth slows and foliage may become yellow or wilt. Roots of affected plants are found to be rotten and there may be lesions at soil level. The causal fungi include Pythium, Phytophthora, Rhizoctonia (Corticium), Fusarium, and Helminthosporium. Correct planting conditions, seed dressings, and soil sterilization are the usual preventative measures.
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