Ustilago. Corn Smut. Ustilago maydis.

Botanical name: 

Ustilago. U. S. 1880. Corn Smut—The genus Ustilago belongs to the Ustilaginaceae, all the members of which generally develop their spores in the ovary or anthers of the host plant, forming a slimy mass, which in maturing becomes a black dust made up of spores. They produce the smut in cereals. Ustilago Maydis (DC.) Tul. is produced on the stems, the pistils (corn grains), and the male inflorescence (tassel) of the Indian corn. It is specifically characterized by its minute spherical spores, about 0.007 mm. in diameter. It is abundant in the United States. Upon the corn the smut appears in masses, varying in size from a cherry to a child's head; These masses are smooth, irregularly globose, or sometimes lobulated, having at first a livid, bluish tint, and then becoming blackish, and finally bursting and emitting the black contents, consisting of innumerable globose very minute spores, each of which is covered with beautiful little pointed processes. In a dried state the masses are blackish and covered with a black powder.

C. H. Cressler found in ustilago an alleged alkaloid, secaline (trimethylamine), besides a thick, viscid, fixed oil and a resin soluble in ether, but not in alcohol. (A. J. P., 1861, 306.) Rademaker and Fischer (Nat. Drug., 1887, 296) believed that they had discovered a white, bitter alkaloid, ustilagine, soluble in ether, while H. B. Parsons decided that the fixed oil contained an acid which he provisionally named sclerotic acid; also an amine-like volatile substance extracted by ether. (N. R., March, 1882; also West. Drug., 1894.) A. W. Balch [Journ. Boston Soc. Med. Sci., March, 1901) was not able to find any active substance in the smut.

The belief that corn smut is an abortifacient to the lower animals (A. J. P., Sept., 1861) appears to be without foundation, as in the experiments made by the United States Department of Agriculture in 1898 (Farmers' Bulletin, No. 69) no effect was produced by corn smut given to pregnant cows. The experiments of James Mitchell (T. G. ii, 223) that ustilago abolishes sensation, reflex action, and later general motor power in the frog, is contradicted by the results of Balch, who also found that enormous doses of the substance have no effect upon the color of the cock's comb. In doses of one to two drachms (3.9-7.7 Gm.) it has been claimed by W. A. N. Borland that the fluidextract markedly increases the severity and frequency of the uterine pains in human labor. The whole drift of our present evidence is to show that ustilago is probably inert.


The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.