Abstract
A description is provided for Fusarium oxysporum f.sp. vasinfectum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Gossypium spp., and species of Cajanus, Coffea, Hevea, Hibiscus, Medicago, Ricinus, Solanum and Vigna. DISEASE: Vascular wilt or Fusariosis of cotton is a disease affecting its host at all stages of its growth. Early symptoms on seedlings consist of vein clearing of the leaves followed by necrosis of the interveinal tissue and death of the leaves. On older plants leaves become chlorotic and the vascular tissues show a brown discolouration. Growth is retarded and the plant eventually wilts. GEOGRAPHICAL DISTRIBUTION: Africa: Congo, Central African Republic, Egypt, Ethiopia, Madagascar, Senegal, Somalia, Sudan, South Africa, Tanganyika, Uganda; Asia: Burma, China, Formosa, India, Indo-China, Iran, Iraq, Pakistan, U.S.S.R. ; Europe: France, Greece, Italy, Romania, Yugoslavia; North America, Mexico, U.S.A. (cotton belt); Central America & West Indies: Guatemala, Nevis, Nicaragua, Puerto Rico, Salvador, St. Vincent; South America: Argentina, Brazil, Chile, Colombia, Peru, Venezuela. (C.M.I. Map 362). TRANSMISSION: Soil-borne, but may also be transmitted by water and seed. The pathogen has been recovered from delineated seed obtained from infected cotton plants in the Central African Republic, Congo, Tanganyika and Brazil (32: 186; 33: 143; 40: 754; 41: 389). The percentage infection ranged from 0.2 to 5.0.
