Club Root
Clubroot  Clubroot is a soilbourne fungal disease that can survive up to 20 years in the soil in the absence of a suitable host. Clubroot survives in damp, acid conditions. It is less of a problem in alkaline soils in hot, dry seasons; and spring maturing crops. The disease is spread on infected plant material and contaminated soil. It is easily carried in soil on tools, machinery, foot wear and infected transplants, which may not show symptoms; Susceptible Plants- Brassicas, wallflower, stocks, and candytuft Symptoms- During initial stages of clubroot, aboveground symptoms may be absent. When present, foliar symptoms consist of stunting, yellowing, wilting, and other signs of a dysfunctional root system. Extensive galling, swelling, and distortion of the roots and hypocotyl are the main symptoms of the disease.
Galled and clubbed roots are often invaded by secondary rot organisms such as soft rot bacteria; this results in the rapid decay of roots, further decline of infected plants, and release of additional inoculum into the soil.
Prevention and Control- Once in the soil, clubroot fungus remains viable for many years. There is no easy way to eliminate it so avoidance is very important. Minimize the spread of the pathogen by using pathogen-free transplants. It is preferable to use transplants that are produced in soil-less rooting mixes in trays. However, if field-grown transplants must be used, then grow transplants in fumigated plant beds; young plants can be infected for some time without indicating infection and cannot always be detected at transplanting. Restrict the movement of contaminated soil (from garden tools) Where gardens are already infested with the clubroot pathogen, applying Garden Lime, Mound fresh compost around crops that have been attacked to encourage health roots. In general, apply lime if soil pH is lower than 7.2. Annual applications are usually necessary. Not all soils respond favorably to this treatment. .
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