90 
Journal of Agricultural Research 
Vol. XXIII , No. 2 
abnormally upward on account of more rapid growth on the under than 
on the upper side. The possibility of a wound stimulus is therefore not 
eliminated. 
GERMINATION at different TEMPERATURES 
Atterberg ( 6) was perhaps the first to call attention to the favorable 
effect of cool temperatures upon the germination of not after-ripened 
cereals. He considered after-ripening as simply the continuation of the 
normal process of ripening, and recommended that, with cereals too 
unripe to germinate well at from 13 ° to 15 0 C. the germination test be 
preceded by drying for eight days at 40° C. He also found that the 
use of alternating temperatures sometimes increased germination of such 
grain. Kiessling (28) got better germination at 12 0 to 16 0 C, than at 
18 0 to 23 0 C, as late as November and better at io° to 14 0 C. than at 
18° to 22 0 C. until late stages of after-ripening, when the comparison was 
reversed. Recently, Stapledon and Adams (59) stated that from 12 0 
to 15 0 C, gave best results with nearly all samples of fresh cereals. Of 
course at the low temperatures the rate of development is very slow and 
germination therefore has to be counted very “ closely ” or else the 
germination test has to be continued over a longer period. 
An alternative is to transfer the grain to a higher temperature for an 
additional day or two as soon as practically all have begun to germinate. 
Table V summarizes the results of a large number of germination 
tests at different temperatures. 
The very favorable effects of temperatures well below 2o°C. is strikingly 
evident. With oats and barley the highest average total percentages 
of germination in two weeks were secured at 5 0 and 9 0 . There were 
very considerable differences in response to temperature between indi¬ 
vidual samples of each kind of cereal. 
Table V .—Germination at different temperatures 
AVERAGE PERCENTAGE BEGINNING TO GERMINATE AT DIFFERENT TEMPERATURES 
Kind of cereal. 
1 
Number 
of 
samples. 
Number 
of 
days. 
s°C. 
5 -C. 
12 ° C. 
16 0 C. 
19 ° C. 
22* C. 
Wheat. 
! 16 
{ 
5 
54 
8 9- 5 
89 
88 
5 2 
l 5 
94 
99 
99 
99 
95 
85-5 
f 2 
1 
2 
26 
4i 
37 
28 
Oats. 
7 
5 
3 2 
69 
79 
7i 
6 5 
55 
1 n-14 
87 
88 
85 
77 
72 
68 
f 2 
0 
1 
3 
17 
13 
5 
Barley. 
3 
5 
28 
63 
67 
6 3 
45 
24 
l 11-14 
95 
94 
86 
80 
PERCENTAGE OF GERMINATION OF SAMPLES SHOWING MAXIMUM TEMPERATURE EFFECT 
Wheat. 
1 
/ 2 
0 
0 
50 
40 
22 
8 
i 5 
88 
96 
98 
84 
40 
16 
Oats. 
/ 5 
44 
48 
84 
94 
66 
50 
l 5 
82 
94 
92 
68 
52 
48 
Barley. 
1 
5 
20 
80 
86 
80 
56 
20 
