ABSTRACT
Seedborne and soilborne organisms, both flora and fauna, acting singly or in combination, produce the seedling disease complex of cotton (11,17). Most of the pathogens involved are ubiquitous fungi that are associated with many plant species in addition to cotton. Nematodes are often associated with the fungi, and combinations of organisms can cause more severe disease problems than either alone. Each pathogen produces effects that contribute to a complex of interrelated symptoms caused by several organisms simultaneously attacking seed and seedlings. The disease symptoms include pre-emergence rotting of seed and seedlings, necrosis of seedlings both before and after emergence, and chlorosis, stunting and wilting of seedlings. The incidence of seedling disease is influenced by the quantity and virulence of pathogens, and adverse temperature and excessive soil moisture. Any condition that favors faster development of the pathogen than the host can be detrimental to stand establishment (8).
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