Control of verticillium and sclerotinia of chrysanthemums with systemic fungicides

Verticillium wilt caused by Verticillium albo-atrum and sclerotinia white rot caused by Sclerotinia sclerotiorum are two diseases of commercial chrysanthemums in San Diego County. Previously, the only control of verticillium wilt was soil treatment with chloropicrin or steam prior to planting. In young plants sclerotinia can be prevented by these same soil treatments but tests reported here also show control possibilities by pre-plant application of fungicides on the soil surface. Sclerotinia control may be variable in a maturing cut-flower crop under moist greenhouse conditions where the fungus attacks high on the stems.