STUDIES ON THE GROWTH OF FRUIT BODY OF FUNGI: III. OCCURRENCE, FORMATION AND DESTRUCTION OF INDOLE ACETIC ACID IN THE FRUIT BODY OF AGARICUS BISPORUS (LANGE) SING

Considerable amounts of auxin, mostly IAA, in acid and boundforms, occur in gills, pilei and stipes of the mushroom, Agaricusbisporus. Stipe elongation is not stimulated by applicationof IAA. The juice squeezed from the fruit body has an activity to convertL-tryptophan into IAA. This activity is not lost by heating.The substance(s) responsible for it passes through cellophane,and is insoluble in some organic solvents, such as petroleumether and benzene. The amount of IAA produced depends exactlyon the amount of the extraction residue used for the reaction.Since the activity decreases as thiosulfate is added increasingly,the active principle seems to be some strong oxidizing substance(s). ¹ This paper was read on October 25th, 1958, at the 23rd annualmeeting of the Botanical Society of Japan, held at Fukuoka,Japan. ² This investigation has been aided by a grant from the ROCKEFELLERFoundaion. ³ Present Address: J. W. GIBBS Research Laboratory, Departmentof Botany, Yale University. New Haven, Conn., U.S.A. (Received June 6, 1961; )