74 
Journal of Agricultural Research 
Vol. XXVII, No. z 
Table III .—Data on relation of anchorage to lodging in some closely related inbred strains 
of Yellow Dent corn, as measured by their resistance to a vertical pull, the corn being planted 
May 22, IQ22, near Bloomington, III., in brown silt loam soil, and plants pulled Sep¬ 
tember 27-28 
Pedigree num¬ 
ber. 
B-i-i-i-R- 3 - 
B-1-1-1-R-7. 
B-i-i-i-R-8. 
B-i-i-i-R-io 
B— 1-1-1-1-2.. 
Num¬ 
ber of 
plants 
pulled. 
Mean pulling re¬ 
sistance per plant. 
Difference in mean pulling resistance 
per plant based on B-1-1-1-R-3. 
Mean 
plant 
height. 
Plants 
leaning 30° 
or more. 
Erect 
plants. 
Mean of 
both 
erect and 
leaning 
plants. 
Erect 
plants. 
Differ¬ 
ence/ 
P.E. 
[ 
Both 
erect and 
leaning 
plants. 
Differ¬ 
ence/ 
P. E. 
37 
40 
Inches. 
82. 6± 1.1 
Num¬ 
ber. 
0 
Per 
cent. 
0.0 
Pounds. 
240. o±7.1 
228. o±6.1 
Pounds. 
240. odh 7.1 
224.6±6.0 
Pounds. 
Pounds. 
96. odho. 8 
1 
2*5 
12. o± 9.4 
i -3 
15 - 4 ± 9-3 
1. 6 
36 
95 - 4 ±i -3 
5 
13-9 
183.9 ± 9-4 
173. o±9.0 
56.1 dh ii- 8 
4 - 7 
67. o±n. s 
5-8 
39 ; 87 - 3 ±°- 7 
25j89- 6±i-o 
14 
25 
3 S -9 
! 100.0 
i5S-3±lo-o 
! 
144- 3 ± 7 - S 
120.1 ± 8 .1 
84. 7± 12.2 
6. 9 
.! 
95 - 7 ±10. 3 
119- 9±ic«8 
9-3 
11. 1 
Table IV .—Data on root anchorage of 25 erect plants from each of three closely related 
inbred strains of Yellow Dent corn grown in contiguous rows, the corn being planted 
May 22, IQ22 , near Bloomington, III., in brown silt loam soil, and root anchorage 
data taken September 28 
Pedigree number. 
Num¬ 
ber of 
plants. 
Mean pulling 
resistance per 
plant. 
Difference in mean 
pulling resistance 
per plant based 
on G-4-2. 
r 
Odds. 
1 
j 
Pounds. 
Pounds. 
Per cent. 
Gr—4—2. 
25 
361-5 
G-4-3. 
25 
328.8 
3 2 -7 
9.0 
5 : 1 
C-4-4. 
25 
242.6 
118.9 
32.9 
999 : 1 
EXTENT OF ROOT SYSTEMS 
Root counts on plants grown under field conditions are given in 
Table V. Plants of the strain susceptible to rootrot and also of the 
strain susceptible to leaf firing had a, significantly smaller number of 
main roots than plants of the good strain, 20.0 ± 1.6 roots and 15.4 ±0.7 
roots compared with 33.0 ±0.8 roots, respectively (PI. 2). There was 
no real difference in mean plant height of the three strains. Such data 
not only throw considerable light on the root-anchorage data presented 
in Table I, but suggest a fundamental cause for the initial wilting of 
the leaves of the strain susceptible to leaf firing. In this strain there 
seemed to be an actual deficiency in the root system compared to the 
vegetative growth above ground. During periods of rather low soil 
moisture and high transpiration, such a small root'system could hardly 
be expected to supply the needs of the plant. Differences in the root 
systems of the good strain and the strain susceptible to leaf firing are 
illustrated in Plate 2. 
The results from root examinations made August 17-25 are given in 
Table VI. There was a great increase in growth in all parts of the plant 
during the period between July 18 and August 17-25. The great 
increase in number of roots is in accord with the findings of Weaver, 
Jean, and Crist. 4 
4 Weaver, John E., Jean, Frank C., and Crist, John W. development and activities of roots 
.of crop plants, vi, 117 p., 42 fig., 14 pi. Washington, D. C. 1922. Bibliography, p. 116-117. (Carnegie 
Jnst. Wash. Pub. 316.) 
