Treatment of Cotton Seed 
21 
2. While a temperature of 35° C. permits good germination of cotton 
seed, it inhibits the growth of the fungus which causes anthracnose and 
prevents the development of the disease. 
3. At 20° germination of cotton seed and growth of the seedlings are 
good, but growth of the anthracnose fungus and the development of the 
disease are slower than at higher temperatures. 
4. Temperatures between 25 and 30° C. are to be regarded as most 
favorable for the germination of cotton seed when it is desired to de¬ 
termine the percentage of infection from anthracnose by the method 
described in this paper. At these temperatures germination of the seeds 
is rapid and complete and timely development of anthracnose on inoculated 
seedlings is assured. 
DRY HEAT TREATMENT OF COTTON SEED FOR CONTROL OF ANTHRACSE 
EXPERIMENTS WITH SEED IN SMALL LOTS 
The experimental work bearing directly on the control of cotton anthrac¬ 
nose was begun in a preliminary way by subjecting air dry cotton seed to 
temperatures of 70, 80, 90, and 100° C. and subsequently determining their 
ability to germinate. The data obtained in many of these preliminary 
tests later proved to be of doubtful value and had to be discarded, as noted 
above, because of the great variation in temperature which obtains between 
different positions on the same shelf of the oven used for heating the seeds. 
Inasmuch as several lots were usually heated concurrently, and no record 
of the position of the individual lot in the oven was kept, it was impossible, 
when this error was discovered, to tell, even by aid of the temperature map 
of the oven, the exact temperature to which a given lot had been subjected. 
Since differences of 10 to 15 degrees existed between lots heated at the same 
time, it was necessary to repeat many of the earlier tests, placing the seed 
only in positions known to have the temperatures indicated by the oven 
thermometer. Table VI gives the data obtained from such of the preliminary 
tests as are known to be trustworthy and from others made later in repeti¬ 
tion of those which were discarded. 
TABLE VI 
Resistance of Air Dry Cotton Seed to Temperatures 70, 80. 90 and 100° C. 
Exp. 
No. 
Lot 
No. 
Temp. 
Deg. 
C. 
Time 
Hrs. 
Per Cent Germination 
Water Content 
of Seeds in 
Per Cent of 
Wet Wt. 
Year When 
Seed Were 
Grown 
Treated 
Untreated 
1 
1 
100 
Vi 
0 
100 
1919 
2 
1 
90 
M 
0 
100 
1919 
3 
1 
80 
l 
34 
98 
1921 
3 
2 
80 
4 
24 
98 
1921 
3 
3 
80 
15 
12 
98 
1921 
4 
1 
80 
1 
5 
98 
1922 
5 
1 
70 
6 
70 
90 
1919 
5 
2 
70 
24 
40 
90 
1919 
5 
3 
70 
72 
60 
90 
1919 
6 
1 
70 
24 
98 
92 
8.3 
1923 
6 
2 
70 
48 
90 
92 
8.3 
1923 
7 
70 
24 
80 
97 
14.3 
1923 
7 
2 
70 
24 
78 
97 
11 .0 
1923 
8 
1 
70 
24 
73 
71 
7.98 
1924 
8 
2 
70 
24 
60 
72 
10 .65 
1924 
8 
3 
70 
24 
49 
77 
13 .22 
1924 
