The diseases are caused by a fungus and are controlled by making foliar applications of a suggested fungicide. Belly rot is a soilborne fungus disease that attacks the developing fruit. Use mulches to prevent fruit contact with the soil. Blossom blight is a fungal disease that attacks flowers and young fruit. It appears during periods of rainy, humid weather and disappears when it dries out.
Bacterial wilt spread by cucumber beetles is devastating.
Plants are infected with bacterial wilt disease by the natural attack of cucumber beetles. The disease organism overwinters in the beetles from one year to the next. The beetles hibernate among the plant debris and weeds around the garden. Plants are usually infected with the disease-causing bacteria long before they show any symptoms. When the vines wilt and collapse, it is too late to prevent the disease.