Growth of M. alpina ATCC 32222 and its uracil auxotrophs on different media. The mycelium of each strain (U+, M. alpina wild type; U1, MAU1; U2, MAU2; U3, MAU3) was transferred to each plate and incubated at 28°C for 3 days. GYU5FOA, GY medium supplemented with 0.05 g/liter uracil and 1 mg/ml 5-FOA; SC, SC medium; SCU, SC medium supplemented with 0.05 g/liter uracil; SCOA, SC medium supplemented with 0.5 mg/ml orotic acid. The circle in the middle indicates the position of each strain on the plate.