VARIETAL SUSCEPTIBILITY OF OATS TO SMUTS 33 
appears to be highly susceptible to Ustilago avenae but somewhat 
resistant to U. levis. 
As a group the side oats are extremely susceptible to both smuts, 
and no other striking cases of resistant varieties have been dis- 
covered. 
RESULTS FROM AVENA STERILIS 
Four strains of the wild species (Avena sterilis L.) have been grown. 
These strains are closely related to Avena ludoviciana. Two of 
them (S. N. 27 and S. N. 28) have proved to be moderately suscep- 
tible. The results have varied considerably from year to year and 
at the different stations. A third strain (S. N. 252) has had com- 
paratively high percentages of infection in the one year in which it 
was grown at Aberdeen, Idaho. S. N. 128 has had lower percent- 
ages of infection in the one year at Aberdeen and one year at 
Brooklyn. 
Ten cultivated varieties of the Avena sterilis type have been grown. 
Seven different strains of Burt (S. N. 67, 74, 75, 175, 253, 254, and 
339) have been grown. S. N. 67 has had comparatively low per- 
centages of infection, especially with Ustilago levis, except at Aber- 
deen in 1919 and at Columbia in 1920. S. N. 74 has shown con- 
siderably higher percentages of infection. S. N. 75, received under 
the name of Early Ripe, usually has shown low percentages of in- 
fection, the important exceptions being at Aberdeen in 1919 and 
Ames in 1920. S. N. 175 and S. N. 253 consistently have had very 
low percentages of infection. Strain S. N. 254 had rather high 
infection at Brooklyn in 1921. S. N. 339 has given results slightly 
above the average for the other strains. This strain, however, was 
from a commercial source and may not have been a pure Burt 
varietv; no special effort was made to establish a pure-line Burt in it. 
Four different strains of Fulghum (S. N. 129, 257, 264, and 368) 
were grown. S. N. 129 was obtained from Etheridge under the 
name of King. S. N. 264 and S. N. 368 are known as Kanota, a 
strain of Fulghum distributed by the Kansas Agricultural Experi- 
ment Station. A total of 3,252 plants of Fulghum (S. N. 129) was 
grown from the seed inoculated with Ustilago avenae. Of these, 
only 6 plants were infected. In the series inoculated with U. levis 
2,946 plants were grown, of which 9 were infected. Fulghum (S. N. 
257) has almost as good a record, as only 24 plants out of a total of 
3,917 in the U. avenae series and only 14 plants out of a total of 3,989 
in the U. levis series were infected. The two strains of Kanota 
(S. N. 264 and S. N. 368) developed only 15 infected plants out of 
a total of 1,491 after inoculation with U. avenae and 10 infected plants 
out of a total of 1,344 after inoculation with U. levis. 
Seven different strains of Red Rustproof oats have been grown. 
Strains S. N. 131, 262, 338, and 354 nave given slightly variable 
results, but on the whole the percentages of infection have been 
small. On the other hand, strains S. N. 263, 265, and 355 have given 
consistently low percentages of infection. 
All the other varieties of Avena sterilis grown, namely, Black 
Algerian (S. N. 261), Red Algerian culta (S. N. 256), nigra (S. N. 
130), and Selection (S. N. 132), have proved resistant, although in 
some cases the number of plants obtained was relatively small. 
A selection from Italian Rustproof (S. N. 260) has given low per- 
