Jan. 12,1924 
75 
Anchorage and Extent of Corn Root Systems 
Table V.— . Data from a comparative study of the root systems of three unrelated inbred 
strains of Yellow Dent corn planted June 2, IQ22, at Bloomington, III., in brown silt 
loam soil that previously had produced two crops of corn, and excavated July 18, IQ22 
Character of inbred strains. 
Num¬ 
ber of 
plants 
exam¬ 
ined. 
Mean plant 
height. 
Mean num¬ 
ber main 
roots per 
plant. 
Difference in number of 
main roots per plant 
based on good strain. 
Differ¬ 
ence/?.E. 
Good... 
4 
Inches. 
59 -oil-1 
S 9 - 3 ±i-° 
33*odbo.8 
20.0±1.6 
Number. 
Per cent. 
Susceptible to rootrot.. 
Susceptible to leaf 
7 
13.Oil.8 
39-4 
7.2 
firing. 
9 
S 7 - 2 ± 2-4 
i 5 - 4 ±o -7 
I7.6il. 1 
53-3 
16.0 
Table VI. —Data from a comparative study of three unrelated inbred strains of Yellow 
Dent corn planted June 2, IQ22, at Bloomington, III., in brown' silt loam soil that 
previously had produced two crops of corn, and excavated A ugust 17-25 
Mean number of 
Mean total length 
Mean 
lateral roots per 
of all lateral roots 
per¬ 
plant on six 
per plant on six 
Num¬ 
Mean 
Mean 
cent¬ 
6-inch pieces of 
6-inch pieces of 
Character of strain. 
ber of 
, Mean 
* height. 
cir- 
num¬ 
age of 
main roots. 
main roots. 
plants 
cum- 
ber of 
rotted 
exam¬ 
fer- 
main 
roots ic 
> 
ined. 
ence. 
roots. 
inches. 
2-8 
10-16 
2-8 
10-16 
inches 
below 
inches 
inches 
inches 
surface. 
below 
below 
below 
below 
surface. 
surface. 
surface. 
surface. 
Good. 
| Inches. 
Inches, 
Inches. 
Inches. 
OO O 
3-41 
58.5 
9-7 
39 T -° 
244.6 
774-7 
423 - 6 
Susceptible to rootrot. 
Susceptible to leaf 
y 
yy • w 
9 
109.1 
3-45 
5 i -7 
96.7 
293.1 
96.0 
334-4 
103 - 5 
firing. 
9 
102.0 
3-40 
57 -o 
4.0 
391.0 
160.2 
423.7 
A Q 
Difference between 
205.9 
good strain and 
strain susceptible to 
rootrot . 
10.1 
6.8 
87.0 
97-9 
168.6 
330-3 
320.1 
Percentage difference 
between good strain 
and strain suscepti¬ 
ble to rootrot ...... 
10.2 
11.6 
trn *1 
25.0 
i,49 2 :i 
69.0 
348:1 
43 -i 
i,999:i 
75-6 
4 , 544 :i 
Odds. 
0 , qoo:1 
C2C* I 
Difference between 
y>yyy • 1 
oy • 
good strain and 
strain susceptible to 
leaf firing. 
84.4 
2 CT O 
214.7 
Percentage difference 
between good strain 
and strain suscepti¬ 
ble to leaf firing. ... 
■3 a c 
45-3 
81:1 
Crt 
Odds. 
Jr * J 
' 2AA ’ T 
50. u 
1,350:1 
i 
4 - A 
The difference of 6.8 in mean number of main roots between the good 
strain and the strain susceptible to rootrot, although not large, is rather 
significant in view of the odds of 59 to 1. Plants of the strain susceptible 
to leaf firing showed a very large gain in number of main roots during 
the period between July 18 and August 25. The number of rotted roots 
in the strain susceptible to rootrot was very pronounced. There was 
little evidence of rootrot in the strain susceptible to leaf firing. 
