Sept, i, 1923 
Puccinia glumarum and Hosts for Variety tritici 
37i 
two different sources. During the course of this work there have been 
several indications that there may be strains of the specialized variety 
Puccinia glumarum tritici , the same as exist in P . graminis tritici , as 
shown by Stakman and Piemeisel (18). During the course of these 
studies evidence has accumulated indicating the possible existence of 
varieties or strains of various grasses which may react very differently 
to a given strain of the parasite. This phase of the question is under 
investigation, 
SUSCEPTIBILITY OF WHEAT VARIETIES TO PUCCINIA GLUMARUM 
TRITICI 
No attempt will be made here to review the very extensive literature 
upon the subject of rust resistance. Complete reviews of the subject 
from various angles have been made by Eriksson and Henning (5), 
Biffen (r, p. 40-44), Comes (j), Nilsson-Ehle (14), and, more recently, 
Henning (8). The study in Europe on the relative resistance of various 
wheats to Puccinia glumarum also has been extensive. As might have 
been foreseen, the results obtained have varied greatly, for the men 
engaged have worked under entirely different conditions, and undoubt¬ 
edly with different strains of the varieties of wheat used as well as with 
different strains of the rust. 
This paper summarizes the results obtained through study of a large 
number of varieties of wheat for resistance to Puccinia glumarum tritici 
as it occurs in western Oregon. The wheat varieties were obtained 
partly from the Office of Cereal Investigations and partly from the 
Department of Farm Crops of the Oregon Agricultural College. Every 
precaution has been taken to keep these varieties free from mixtures. 
Both greenhouse and nursery studies were carried on at Corvallis, 
Oreg. In all, 337 varieties and strains of wheat were grown in the rust 
nursery. Only 163 of these are included in Table III. The remainder 
were grown in only one year and therefore are not included. Ninety- 
two varieties were studied under greenhouse conditions. Not all of the 
163 varieties were sown in the nursery in each of the three seasons 
through which the experiments were extended. In 1918 only 72 varie¬ 
ties and strains were grown. In 1919 additional seed was obtained and 
142 varieties and strains were grown. Still other varieties were added 
in 1920. Likewise, not all of tie 92 varieties were grown in the green¬ 
house in any one season. Because of inadequate space and assistance 
it was impossible to study in the greenhouse all of the varieties that were 
used in the rust nursery. 
NURSERY EXPERIMENTS 
In the rust nursery the varieties were all sown in rod rows. In some 
cases replicated sowings were made; in other cases there was only one 
row of each variety. All varieties of which seed was available were 
sown in the fall regardless of whether they were of winter or spring habit. 
Under the climatic conditions prevailing at Corvallis it was found that 
spring varieties, when sown in the autumn, survived the winter in prac¬ 
tically as good condition as the winter varieties. In the first two years 
such varieties as were known to be of spring habit and of which seed was 
available were sown in duplicate rows in the spring. In 1920 all varie¬ 
ties of which seed was available were sown again in duplicate rows in the 
