Potato dextrose agar
(FDA M127)(abbreviated "PDA") and potato dextrose broth (abbreviated "PDB") are common microbiological media made from potato infusion, and dextrose (corn sugar). Potato dextrose agar is the most widely used medium for growing fungi and bacteria which attack living plants or decay dead plant matter.
Potato infusion is made by boiling 200g of sliced (washed but unpeeled) potatoes in water for 30 minutes and then decanting or straining off the broth. Dextrose (corn sugar) is then added (20 g/L) and the medium is sterilized by autoclaving.
Common organisms that can be cultured on PDA are yeasts such as Candida albicans and Saccharomyces cerevisiae and molds such as Aspergillus niger.