Aug. 18, 1923 
Inheritance of Dwarfing in Maize 
3 QI 
When grown under more favorable conditions in greenhouse flats, the 
percentage of dwarf seedlings, which are recognized easily by their short 
broad leaves, is found to approximate closely the expected 25. Thus 
three progenies involving 823 plants gave, respectively, 31.4 ±2.4, 
25.1 ± 1.74, and 21.3 ± 1.43, with a percentage of 24.7 ± 1.02 for the com¬ 
bined totals. 
Measurements were made of five characters of 924 plants of the second 
generation progeny grown at Arlington in 1922. These plants also were 
classified arbitrarily into the three groups of normal, dwarf, and brachy- 
tic stature. In addition, the plants were classed for pericarp color, 
anthers in the ear, and staminate spikes on the ear. These latter might 
better have been measured, since they varied greatly in length and in 
the ratio of the staminate to pistillate portions. The hybrids also 
involved liguleless leaves and were classed with respect to this character. 
The biometrical constants of these characters are given in Table III and 
the percentages of individuals showing them in the three groups and 
in the total population are given in Table IV. 
Table III .—Biometrical constants for the second generation of the dwarf-brachytic hybrid 
grown at Arlington, Va., ig 22 
Stature. 
Total population. 
Normal. 
Dwarf. 
Brachytic. 
Mean. 
<r 
PE. 
Mean. 
V 
PE. 
Mean. 
a 
PE. 
Mean. 
PE. 
Height. 
23-3 
4.00 
O. X 2 
4.87 
0.99 
0.05 
8*55 
1.97 
0.10 
16. 70 
8.86 
0.20 
Length fifth leaf. 
77*0 
10.30 
•30 
40.06 
8.30 
.42 
67.66 
I- 12 
.08 
72.60 
17.90 
.42 
Width fifth leaf. 
9.9 
1.96 
.06 
11.20 
2.19 
. 11 
8.89 
2.04 
.13 
10.10 
2.10 
•os 
Number tassel branches 
18.3 
10.50 
•30 
.69 
i* 3 o 
.06 
20.19 
11.40 
•6s 
14.80 
12.10 
.28 
Total number leaves... 
22. 5 
1.60 
•05 
24. 70 
2.00 
.27 
25.04 
2. 02 
1-57 
22.96 
1.99 
.06 
Leaf index. 
12. 2 
3 *io 
.09 
25*17 
3*90 
. 20 
12.66 
4*51 
.29 
15* 10 
6.38 
•15 
Table IV. —Percentage of plants in the three stature groups having the characters listed 
in column 1 
Characters. 
Stature. 
Total 
population. 
Normal. 
Dwarf. 
Brachytic. 
Brachvtic. 
Per cent. 
PE. 
P#r cent. 
PE. 
Per cent. 
PE. 
Percent. 
18.7 
20.8 
25.8 
22.95 
40.9 
24. 1 
16. 2 
PE. 
0.87 
.91 
•97 
.98 
1.14 
1.49 
.84 
Dwarf.. .. 
Liguleless. 1 
Perfect flowered ears. i 
Staminate spikes.| 
White pericarp. j 
Tassels without branches.| 
j 
27.0 
•6 
26. 2 
20. 9 
2. 2 
1.26 
. 22 
1.28 
1. 65 
•42 
20.3 
100.00 
99.9 
22. 7 
67.8 
1.94 
4. 2 
2.3 
27.9 
4 * 55 
18. 2 
40.3 
2.9 
2.3 
1.21 
1*45 
4 * 36 
.58 
INHERITANCE of size characters 
As was to be expected, the height of the plants as measured in deci¬ 
meters showed a trimodal distribution, the dwarf and brachytic plants 
forming a group at the low end of the scale. The frequency distribution 
for this character is shown in figure 1 and their relative heights are 
shown in Plate 5. 
In the cross between dwarf and anther ear, reported by the Emersons, 
where normal stature also was restored in the F v the distribution with 
respect to height shows the anther ear and normal segregates to be more 
54485—23 - 2 
