84 
Journal of Agricultural Research 
Vol. XXVIII, No. 1 
Table V .—Percentages of normal , abnormal , and total germination of untreated and 
treated seeds of China (C. I. 180) wheat with seed coats unbroken or broken at 
definite locations over the endosperm 
Number of days after sowing 
10 . 
20 . 
30. 
Total germination. 
Percentage and character of germination 
Seed coats 
unbroken 
Seed coats broken over endosperm 
| inch above 
embryo 
On brush end 
On each cheek 
behind embryo 
Un¬ 
treated 
Treated 
Un¬ 
treated 
Treated 
Un¬ 
treated 
Treated 
Un¬ 
treated 
Treated 
Normal 
! 
< 
1 
fc 
1 
1 
13 
1 
525 
1 
& 
< 
■a 
g 
o 
6 
i—i 
I 
< 
13 
g 
o 
fc 
1 
< 
1 
o 
I 
<1 
13 
I 
13 
I 
& 
< 
13 
g 
o 
'a 
1 
< 
97 
97 
97 
0 
0 
0 
93 
96 
96 
0 
0 
0 
99 
99 
99 
0 
0 
0 
15 
15 
15 
40 
49 
51 
95 
95 
95 
0 
0 
0 
9 
9 
9 
15. 
26 
27 
98 
98 
98 
0 
0 
0 
2 
4 
4 
3 
7 
8 
9 
7 
9 
6 
9 
9 
6 
6 
9 
5 
3 
6 
9 
8 
1 
2 
Table V shows that when the seed coats are broken over the endosperm there 
is a severe reduction in normal and total germination (Pl. 3). In the light 
of these data, the original supply of the 33 varieties listed in Table III was 
examined carefully for broken seed coats. It was found that the lots most 
severely injured by treatment invariably showed a high percentage of seed- 
coat breakage. 
During the course of some of the preceding experiments it was observed that 
hand-threshed kernels with unbroken seed coats germinated more slowly when 
the seed was treated. A typical example is shown in Table VI for Leap (C. I. 
4823) wheat. Five hundred hand-threshed kernels were treated on September 
JL, 1922, and dried seven days at room temperature, following which, the treated 
kernels and a like number of untreated from the same lot were sown on Septem¬ 
ber 8, 1922, in soil in greenhouse flats. All of the seed was sown and germinated 
under like conditions. From the date of emergence of the first seedling daily 
records of the number of seedlings which had emerged were taken for one month. 
The results are presented in Table VI. 
Table VI .—Rate of emergence of seedlings from 500 untreated and 500 treated 
kernels of hand-threshed Leap ( C. I. 4823) wheat 
Treatment of seed 
5 
6 
7 
8 
9 
10 
30 
Untreated. 
85 
98 
98 
98 
98 
98 
98 
Treated by the modified hot-water method. 
0 
22 
64 
79 
96 
98 
98 
Percentage of emergence after the 
following number of days 
Table VI shows that the modified hot-water treatment materially affects the 
germination of seeds with unbroken coats, although it may produce no actual 
mortality (PI. 4, A, B, E, and F). Atwood ( 1) has noted the possibility that 
concentrations of formaldehyde which do not materially injure germination 
percentages may materially disturb the physiologic processes related to germi¬ 
nation and subsequent growth. 
