Factors affecting infection of potato tubers byAlternaria solani in Colorado

Potato tubers became infected byAlternaria solani at the time of harvest. Infection occurred only on wounded tubers irrespective of their depth in the soil. The presence of free moisture on unwounded tubers did not increase the incidence of infection, and immature unwounded tubers were not susceptible. Tuber infections may be reduced by allowing tubers to fully mature before harvest or possibly, by applying chemicals to the soil surface.