The formation of wound periderm and the susceptibility of potato tubers to gangrene (caused by Phoma exigua) in relation to rate of fertiliser application and time of planting

Wound periderm on potato slices restricts the penetration of the underlying tissue by Phoma exigua f. sp. foveata. The rate of formation of the wound periderm on slices cut from freshly harvested tubers may be affected by the rate of application of NPK fertiliser and by the time of planting of the crop. These two factors also influence the susceptibility of the tubers to gangrene induced by artificial inoculation, but the correlation between rate of formation of wound periderm and incidence of rot was not consistent.