Annals 
of the 
Missouri Botanical Garden 
Vor. 3 FEBRUARY, 1916 No. 1 
RHIZOCTONIA SOLANI IN RELATION TO THE 
* MOPOPILZ" AND THE *VERMEHRUNGSPILZ " 
B. M. DUGGAR 
Physiologist to the Missouri Botanical Garden, in Charge of Graduate Laboratory 
Professor of Plant EC in the Henry Shaw School of Botany of 
Washington Universi 
Discussing in a recent paper (15) the distribution of Rhiz- 
octonia Solani Kühn (Corticium vagum B. & C.) I made the 
following statements: 
“И is rather surprising to find that R. Solani has received 
relatively little attention in Europe. Although recognized as 
inducing a disease of the potato widely distributed in central 
Europe, and occasionally reported on the beet, yet little careful 
work has been bestowed upon the fungus.” 
T shall now endeavor to show, as definitely as a discussion 
of the literature will permit, that this statement requires ma- 
terial modification. At the same time the evidence indicates 
a considerable extension of the region in which this Rhizoc- 
tonia is important as a seed-bed parasite. The new light on 
the problem is a result of the provisional determination— 
amounting almost to a certainty—that the Javanese ‘‘Mo- 
popilz" and the central European ‘‘Vermehrungspilz’’ are 
identical with Rhizoctonia Solani (Corticium vagum B. & C.). 
Some years ago the writer attempted to determine the pos- 
sible relation of Rhizoctonia to seed-bed or cutting-bench dis- 
eases in Germany, but at that time the literature was scant 
and confusing, so that the effort was unfortunately abandoned, 
largely, ee er, as a result of the suggestions from several 
sourees, that Pythium, Botrytis, and other known forms were 
Ann. Mo. Bor. Garb., VoL. 3, 1916 (1) 
