The Growth-Promoting Effect of Indole-3-Acetic Acid on the Common Cultivated Mushroom, Psalliota Hortensis (Cooke) Lange Forma Albida Lange

A strain of the white-capped form of the common cultivated mushroom, Psalliota hortensis (Cook;e,} Lange forma albida Lange, appeared unable to grow appreciably on a liquid basal medium which contained glucose, asparagine, and mineral salts. Addition of thiamin and biotin increased the growth a little . .A number of other vitamins were without effect. Indole-3-acetic acid (IAA) in concentrations of from 5 to 100 mg/l markedly increased growth, particularly in the presence of thiamin and biotin, but only when the inoculum was floating on the surface of the culture medium. If the inoculum was submerged, addition of IAA had very little effect. The growth of both floating and submerged