154 
BOTANY: CROCKER AND GROVES 
Table I shows the data gained from a single experiment. Three 
things stand out prominently as results of heating: delay in germina- 
tion, fall in germination percentage, and appearance of abnormal ger- 
mination. The abnormal germination (root without stem or stem with- 
out root) are shown in light type. All these characters appear in seeds 
stored for a long time at room temperatures, indicating the likeness of 
the change whether it takes place at a high temperature in a short 
time or at a low temperature acting for a long time. In Table II are 
shown the life durations at various temperatures as found by experi- 
ment and the calculated temperatures for the various life durations. 
We have supplied for another variety of wheat one record of longevity 
by White"^ in which the time was definitely known as eight years and the 
moisture estimated at 12 percent and the temperature at 20^C. In 
all these failure of 75 percent to germinate after nineteen days is chosen 
as the end point. The calculated temperatures of the table were found 
by solving for the constants a and b by the method of least squares 
TABLE II 
Germination Record Turkish Red Wheal 
Theoretical temperature calculated by formula T = a — b log Z 
T = Temp Celsius, Z = Time of Heating, a = 98.88 h = 11.78 
Trial No 
A 
B-C 
D-E-D 
G 
H 
I 
J 
K-L 
N 
N 
0 
P 
7 
8 
9 
10 
15 
18 
45 
50 
50 
120 
315 
8 yrs. 
Found temp 
89.2 
87.7 
87.5 
87.5 
84.4 
84.4 
78.9 
79.1 
78.5 
75.8 
71.3 
20 ± 
88.9 
88.2 
87.6 
87.1 
85.0 
84.1 
79.4 
78.9 
78.9 
74.4 
69.5 
20.9 
from the found values of T and Z, and from these calculating T for the 
various values of Z. 
The rather close agreement between calculated and found values 
indicate that the time-temperature formula for the coagulation of 
proteins can be applied as a temperature-life duration formula for 
seeds, at least under the condition of these experiments. Much more 
work is needed to estabhsh the general appHcation of this principle. 
Several more life durations should be determined for wheat as a meso- 
biotic seed. The life duration with 12 percent moisture should be run 
at several temperatures ranging from 5O-70°C. A large number of 
determinations should also be made with some moisture content between 
16-20%. Such seeds will show much shorter life durations. Deter- 
minations should also be run for 2-3% moisture which will give greater 
life durations. Similar determinations should be made for a macrobiotic 
seed, such as sweet clover for which we have rehable records of longevity, 
as well as a microbiotic form. There are several matters that may limit 
the application of this formula: 
