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AVRDC International Cooperators'

Fact Sheet
Crucifer Diseases

Fusarium Yellows
Fusarium oxysporum f.sp. conglutinans Found in USA, Trinidad, Cuba, Zimbabwe, Philippines and Japan

Damage Symptoms
Cabbage is especially susceptible, but Fusarium yellows also affects other members of the cabbage family. Infected plants first develop a dull yellowish green color in the foliage. Lower leaves and the stem twist to one side and yellowing becomes more intense on one side of the midrib. Yellowing progresses from the lower leaves up the plant, and as it does so, the lower leaves turn brown and drop prematurely. Plants may survive and be severely stunted, but under conditions favorable for disease development the plants are killed. The vascular system develops a brown discoloration.

Conditions for Development
Once established the pathogen persists in the soil for many years. Warm weather is conducive or disease development. The disease may develop at soil temperatures between 16 and 32°C, but optimum temperature is about 27°C. Soil moisture levels and soil pH do not appear to greatly influence disease development.

Control
Fusarium yellows is best managed by use of resistant cultivars. Most current cabbage cultivars possess resistance to Fusarium yellows and should be used in areas where the disease occurs.

Last updated: 2001. Information from: Vegetable Diseases: A Practical Guide. Lowell L. Black, AVRDC. AVRDC Home | Extension Materials Home | Cabbage Home


				
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