A germ tube is an outgrowth produced by spores of spore-releasing fungi during germination.
The germ tube differentiates, grows, and develops by mitosis to create somatic hyphae.[1]
A germ tube test is a diagnostic test in which a sample of fungal spores are suspended in serum and examined by microscopy for the detection of any germ tubes.[2] It is particularly indicated for colonies of white or cream color on fungal culture, where a positive germ tube test is strongly indicative of Candida albicans.[2]