370 
Journal of Agricultural Research 
Vol. XXV, No. 9 
Tabus II .—Results of inoculation of urediniospores of Puccinia glumarum tritici from 
different original arid immediate hosts on numerous wild grasses and cereals —Cont’d. 
Original host. 
Immediate host. 
Plant inoculated. 
Number of 
experiments. 
Number of 
plants. 
Charac¬ 
ter of 
infec¬ 
tion. 
Infec¬ 
tion ob¬ 
tained. 
No 
infec¬ 
tion ob¬ 
tained. 
Inocu¬ 
lated. 
In¬ 
fected. 
Hordeum no¬ 
Wheat . 
Sitanion jubatum . . . 
2 
26 
24 
4 
dosum. 
Do . 
.do. 
Rye. 
I 
18 
0 
0 
Do. 
.do. 
Wheat. 
2 
A 2 
A 
Do . 
Bromus poly¬ 
B. carinatus . 
2 
46 
o'-' 
O 
0 Br. 
anthus. . 
Do . 
Hordeum no¬ 
Elymus condensatus. 
I 
12 
8 
■3 
dosum. 
0 
Do . 
. do . 
Bromus commutatus . 
X 
20 
0 
0 
Do . 
.do . 
Hordeum nodosum . . 
I 
12 
12 
A 
Do . 
.do . 
Dactylis glomerata 
c 
60 
0 
T- 
O 
j 
The list in Table II includes 48 species of wild grasses which have 
been shown to be hosts of P. glumarum tritici . It includes 19 species of 
Bromus, n species of Agropyron, 7 species of Elymus, and 1 species 
each of Hystrix, Sitanion, and Phalaris. Collections have been made in 
the field on 12 additional infected grass hosts, but it has not been possible 
to determine if they were infected with the race which goes to wheat; 
These 12 species include: Agropyron inerme (Scribn. and Sm.) Rydb., 
A. dasystachyum (Hook.) Scribn., A. caninum f Bromus pacificus Shear f 
Bromus sitchensis Trim, Bromus carinatus hookerianus (Thurb.) Shear t 
Bromus brizaeformis Fisch. and Mey., Hordeum caespitosum Scribn., 
Hystrix californica (Boland.) Kuntze, Elymus striatus Willd., Elymus 
macounii Vasey, E. triticoides Buckl., Phalaris paradoxa L., Sitanion 
hystrix (Nutt.) J. G. Smith, Sitanion longifolium J. G. Smith, and Aegilops 
cylindrica Beauv. 
Only one specialized variety apparently has been used in these inocula¬ 
tion experiments, and this appears to be Puccinia glumarum tritici 
Erikss. & Henn. There are some indications that at least one other 
variety is present in the United States. This probably is Puccinia 
glumarum hordei Erikss. & Henn., as indicated by the fact that barley 
has been found heavily infected in a few instances, while the race com¬ 
monly found on wheat does not pass readily to barley. There also is 
evidence that the rust on Hordeum murinum may not be the variety 
commonly found on wheat. A discussion of these varieties is reserved 
for a later paper. 
In only one case in Table II does there occur a difference of more than 
two in the grade of infection recorded when the same host was inoculated 
with the rust taken from the different hosts. When Bromus sterilis was 
inoculated with rust spores from Hordeum jubatum the infection was 
recorded as 1. When spores were taken from Bromus marginatus and 
from Elymus glaucus the result was a grade of 4 in each case. There 
are two possible explanations for these results. There may have been 
two strains of Puccinia glumarum tritici involved, or it is possible that 
there were two strains of Bromus sterilis used, as the seed came from 
