PUCCINIA GRAMINIS POAE ERIKSS. AND HENN. IN 
THE UNITED STATES 12 
By E. C. Stakman, Plant Pathologist, Division of Plant Pathology and Botany , 
Department of Agriculture , University of Minnesota , and Pathologist , Office of 
Cereal Investigations , Bureau of Plant Industry , United States Department of 
Agriculture , and M. N. Levine, Pathologist , Office of Cereal Investigations, Bureau 
of Plant Industry , United States Department of Agriculture . 
Eriksson and Henning (4), 3 in 1896, first described Puccinia graminis poae on 
Poa chaixi Vill. Eriksson (2) later showed that it could infect Poa caesia Smith, 
P. compressa L. and P. nemoralis L., and that aecia were formed on Berheris 
vulgaris L. The following grasses were inoculated by Eriksson but did not 
become infected: Briza media L., Festuca elatior L., F. ovina L., F. pilosa Haller, 
Hordeum vulgare L , Koeleria cristata var. gracilis A. Gray and Phleum boehmeri 
Wibel. Jaczewski ( 5 ) recorded the occurrence of this form on Poa compressa 
L. in Russia, and stated that it also could infect P. pratensis L. and P. serotina 
Ehrh., but not Agropyron repens (L.) Beauv., Avena saliva L., Bromus inermis 
Leyss., B, secalinus L., Dactylis glomerata L., Hordeum vulgare L., Secale cereale L., 
and Triticum vulgare Vill. Both Eriksson and Jaczewski called P. graminis poae 
“scharf fixiert” and Eriksson designated it as “ Isophage ,” because it was con¬ 
fined to a single genus, Poa. 
The writers have not been able to find records of the occurrence of P. graminis 
poae in the United States. Neither Carleton ( 1) nor Stakman and Piemeisel (14) 
mentioned it; and the writers did not find it during the course of extensive 
field observations previous to 1923. Several specimens of what appeared to be 
P. graminis on Poa spp. have been sent to the writers, but the amount of rust 
always was small and no infection was obtained as a result of artificial inoculations 
until inoculations were made with material obtained from Michigan in the fall 
of 1922. 
In the fall of 1922 Donald G. Fletcher and Walter F. Reddy observed very 
heavily infected Poa compressa near barberry bushes in the vicinity of Pontiac, 
Mich., and sent material to the writers for identification. There were few 
urediniospores on the plants, the rust being mostly in the telial stage. 
In order definitely to establish the identity of the rust inoculation experiments 
were made. On account of the paucity of uredinial material it was necessary 
to start with teliospores. The results of these experiments are given in Table I. 
In the summer of 1923 plants heavily infected with the uredinial stage were col¬ 
lected and additional inoculations made, the results of which are given in Table II. 
1 Received for publication March 12, 1924. 
2 Cooperative investigations between the Office of Cereal Investigations, Bureau of Plant Industry, United 
States Department of Agriculture, and the Department of Agriculture of the University of Minnesota. 
Published with the approval of the Director, as Paper No. 426 of the Journal Series of the Minnesota 
Agricultural Experiment Station. 
3 Reference is made by number (italic) to “Literature cited,” pp. 647-548 
Journal of Agricultural Research, 
Washington, D. C. 
( 541 ) 
Vol. XXVIII, No. 6 
May 10,1924 
Key No. GG-388 
