10 
BULLETIN 1383, U. S. DEPARTMENT OF AGRICULTURE 
The grain was left to dry at room temperature until October 20, when 
both untreated and treated seeds were sown in a triplicate series in 
rod rows at the rate of 6 pecks per acre. The results are presented 
in Table 5. A zero in the table indicates that no smut was found in a 
complete examination of the plants in all three rows. When less than 
1 per cent of smut was present it is shown as T (trace) , and the total 
number of smutted heads found in an examination of all three rows 
is given in parentheses. The other data represent the average 
percentages of smut determined by making a count of 200 heads in 
each of the three rows in a set. 
Table 5. — Percentages of loose smut and bunt in three lots of Goens wheat grown 
from seed untreated or treated with hot wateQ as specified, and sown in the field 
at Arlington Experiment Farm October 20, 1921 
[T=trace (less than 1 per cent). The figures in parentheses show the number of smutted heads found in 
all three of the triplicated rows] 
Treatment of the seed 
Percentage of loose smut 
Percentage of bunt 
Duration 
Lot 18 
Lot 20 
Lot 21 
Lot 18 
Lot 20 
Kind and temperature 
Hours 
Min- 
utes 
Lot 21 
Untreated. 
3.8 

TO) 













T(l) 
12.3 














T(l) 
T(l) 
6.0 
















43.0 
T(5) 
4.5 
2.0 
1.0 
2.0 

T(9) 
T(6) 



T (10) 
T(9) 
T(2) 


47.6 
T(5) 
1.5 
4.0 
2.0 
1.0 
1.0 
1.0 

T(6) 
T(3) 
T(6) 
T (10) 
T(6) 
T(l) 


45.8 
T (7) 
Single-bath method: 
At46°C 
I ! 
[ 2 
2 
1 2 
2 
I 3 
i 1 
1 
1 
1 
30 
30~ 
"""is" 
30 
45 
""40" 
50 
35" 
15 
6.0 
2.0 
At47°C 
At48°C 
At49°C. 
At 50° C 
At51°C 
4. 5 
4.5 
T(3) 
T(3) 
1.0 

T(3) 
T(10) 
T(6) 
T(9) 
T(6) 


Table 5 shows that all of the treatments completely controlled loose 
smut except those at 46° C. for 2 hours and 30 minutes, at 50° C. for 
1 hour and 15 minutes, and at 51° C. for 1 hour. These treatments 
reduced the amount of loose smut to a slight trace. In spite of an 
unusually heavy infestation, bunt infection was reduced to a trace or 
completely controlled by all of the treatments except those at 46° C. 
and by the treatments at 47° C. for time periods less than 2 hours and 
45 minutes. The treatments at 50° and 51° C. effectively controlled 
both loose smut and bunt, but reference to Table 4 shows that they 
severely injured the seed. The treatments at 49° C. for 1 hour and 35 
minutes, and at 48° C. for 1 hour and 40 minutes, for 1 hour and 50 
minutes, and for 2 hours completely controlled loose smut and 
reduced bunt infection to a trace, and the treated seed germinated as 
well (Table 4) as that from the longer treatments at 47° C, which 
approximated their efficacy in smut control. 
Table 5 shows that treatments at lower temperatures and of longer 
duration are more effective in controlling loose smut than in control- 
ling bunt and that treatments at higher temperatures and of shorter 
duration are more effective in controlling bunt than they are in 
controlling loose smut. 
