Emergence of silver scurf (Helminthosporium solani) as an economically important disease of potato

During the 1990s, silver scurf (causal agent Helminthosporium solani) emerg ed as an economically important disease of table stock and processing potat oes (Solanum tuberosum). The pathogen attacks the periderm of the potato tu ber causing blemishes. The disease cycle of silver scurf has both field and storage phases. Primary infection occurs in the field and high relative hu midity favours the spread and increase of silver scurf In potato stores. Co ntrol of the disease by chemical and cultural practices remains difficult. Increase in disease has been attributed to H. solani isolates resistant to the postharvest fungicide thiabendazole (TBZ). Polymerase chain reaction (P CR)-based detection methods for H. solani and TBZ-resistant isolates are ra pid and more specific than traditional identification. This review discusse s the biology of the pathogen, epidemiology of the disease, detection of th e pathogen and integrated control measures for the management of silver scu rf in both field and potato tuber stores.