REPORTS ON RESEARCH FOR 1931 
Plant Pathology 
By GrorcE M. REED 
Studies on the Inheritance of Resistance of Oat Hybrids to Loose 
and Covered Simut 
In the Annual Report for last year we described briefly the ex- 
periments on the second generation plants of a large number of 
fu 
( 
sistance. Altogether, the second generation plants of fifty-two 
different crosses were studied. During the past season we have 
erown a large number of third generation progenies from most of 
these hybrids. Usually, two sets of seed from each progeny were 
planted, one set inoculated with the loose smut and the other with 
the covered. Altogether, more than 3,000 different sets of I’, 
progenies were grown, each one including 20 to 25 individuals. 
As described in the previous report, these various oat hybrids 
involve quite distinet types of combinations of smut resistance ; 
f hybrids from the standpoint of 
iferent oat hybrids involving various combinations of smut re- 
— 
at least six different groups o 
smut resistance have been studied : 
1. In the first group, one variety resistant to both loose and 
covered smut was crossed with another variety which is sus- 
ceptible to both smuts. In the hybrids Hull-less & Black Mesdag, 
Silvermine & Black Mesdag, and Early Champion & Black Mes- 
dag, we have the combination of Black Mesdag, entirely resistant 
to both smuts, while the other varieties are susceptible. Addi- 
tional data on these different hybrids were obtained during the 
past year. These, together with the data obtained in previous 
years, have been assembled and are practically ready for publica- 
— 
tion. 
A series of similar crosses involving the variety Markton, which 
is resistant to both smuts, crossed with the susceptible varieties 
vave been made. Many 
— 
Canadian, Early Champion, and Victor, 
third generation progenies of these crosses were grown, and the 
results were in fair harmony with those obtained for the second 
generation, 
