38 
both smuts in these hybrids is controlled by distinct single fac- 
tors. Hybrid 66 involved Danish Island, susceptible to loose 
smut and moderately so to the covered, and Monarch, susceptible 
to the covered smut. A single factor relationship for resistance 
to loose smut, with resistance dominant, was indicated. In the 
inheritance of resistance to covered smut, however, susceptibility 
appeared to be dominant. 
Several new crosses between oat varieties were made in 1936, 
the first generation plants being grown last year. The inocu- 
ated second generation plants are now growing and, in the 
coming year, will furnish data on the mode of inheritance of 
resistance in these particular crosses. 
Physiologic Races of the Oat Smuts 
Additional experiments were carried out with collections of 
both loose and covered smuts in order to determine the extent of 
their physiologic specialization. A new specialized race on Black 
Mesdag was obtained. This variety is noted for its high degree 
of resistance to all races of both loose and covered smuts hitherto 
known, except the Fulghum races of covered smut. A collection 
of covered smut obtained from Prof. H. L. Shands, University of 
Wisconsin, Madison, Wis., appeared to be quite distinct. 
We have continued our cooperation with Mr. T. R. Stanton 
on physiologic specialization of the oat smuts. The Division of 
Cereal Crops and Diseases is especially interested in the develop- 
ment of new varieties of oats which show a high degree of re- 
sistance to various diseases, including the smuts. Several of the 
new promising strains were forwarded by Mr. Stanton in order 
to have them tested with our known specialized races of both 
species of smuts. There were sixteen selections of the cross 
Victoria X Richland which were tested with 11 collections of 
loose smut and 8 of the covered. Twenty promising selections, 
involving several different parental varieties, also were tested 
with these same collections of smut. Practically all of these 
proved to be highly resistant. Another series of thirty-five selec- 
tions of a cross between Richland and Fulghum were tested 
particularly with the Red Rustproof and Fulghum races of smuts. 
These selections have been developed at the Kansas Agricultural 
