Black dot is one of the most important blemish diseases for the potato packing industry and can cause a significant decrease in produce quality through downgrading and consequent economic loss. This guide is aimed at helping growers and store managers manage the risk of damages from this disease.
Of all pests and diseases of potatoes in Great Britain, infestation by potato cyst nematodes (PCN), or eelworms, is the most damaging. Yield losses depend on pest populations, soil type and potato variety, with a range of 1–35% in trials, with infestations at 10–20 eggs per gram of soil.
PMTV is one of two viruses causing spraing in potato. Infections are commonly associated with tuber internal blemishing (see also TRV). This is a significant cause of rejections of both ware and processing crops. Symptoms do not increase during storage.
Skin spot (Polyscytalum pustulans) is a fungal disease of potato tubers which is generally symptomless until after approximately 2 months of storage, when the infected tissue begins to show spots on some varieties.