Methods of measuring the prevalence of pathogenic fungi on potato tubers

Methods are described whereby the prevalence of pathogenic fungi on seed potato tubers can be measured quickly and quantitatively. Eye-bearing plugs of tuber tissue, 8 mm diameter by 10 mm long, are excised, incubated over water at 15 °C for 5 days and then examined microscopically. The occurrence of fungi and macroscopic tuber symptoms are recorded directly on punched tape and tabulated by computer.