200 
Journal of Agricultural Research 
Vol. XXVII, No. 4 
Table XV .—Summary of data presented in Table XIV 
Points of Comparison. 
Control. 
Inoculated. 
Increase or decrease following 
inoculation. 
A. 
stewarti. 
C, acre- 
montum. 
A. stewarti. 
C. acremonium. 
Mean percentage final field 
Per cen /. 
Odds. 
Per cent. 
Odds. 
stand. 
97-9 
97-5 
96.0 
0.4 
I O 
Mean number of suckers 
x • V 
per plat._ _ 
5 -o 
15-8 
33*3 
216.O 
>999:1 
566.0 
>999:1 
Mean number of purple 
stalks per plat. 
2.1 
2. I 
5-3 
I 5 2 .4 
>999:1 
Mean number of prolific 
stalks per plat. 
1.6 
2.1 
3-3 
3 I *3 
15:1 
106.3 
195 :1 
Mean number of barren 
stalks per plat. 
7-4 
9.6 
9.9 
29.7 
554:1 
33*8 
356:1 
Mean number of nubbin 
ears per plat. 
2.6 
3.8 
5*9 
46.2 
78:1 
126.9 
>999:1 
Mean total acre yield 
(bushel) per plat. 
90.0 
84.8 
8s -5 
“ 5.8 
554:1 
“ 5 *° 
199:1 
Mean acre yield of market¬ 
able com (bushel) per plat. 
68.6 
59 -i 
60.7 
-13.8 
>999:1 
“I !.5 
>999:1 
The nearly disease-free control (Table XVI) was a composite of seed 
ears selected from apparently healthy plants and showing no evidence 
of rotting or infection when tested on a limestone-sawdust table germ- 
inator. This strain of Yellow Dent com is the result of several years 
careful plant and germinator selection to avoid seed from plants affected 
with any of the root, stalk, and ear-rot diseases. Com grown from this 
seed was highly resistant to injury following inoculation with Gibberella 
saubinetii, but was damaged to the extent of 12.9 per cent by inoculation 
with Cephalosporium acremonium. Although care had been exercised 
to avoid plants showing purple leaves and multiple ears, it is probable 
that many ears were included from year to year that had grown on 
plants more or less infected with C. acremonium. This fact may account 
for the greater susceptibility of this com to C. acremonium than to 
G. saubinetii. It is also interesting to note that the nearly disease-free 
control com was not equally susceptible to the two vascular diseases 
induced by C . acremonium and A. steward, respectively, being rather 
susceptible to the former, but highly resistant to the latter. 
The other lots of seed referred to in Table XVI were furnished by three 
representative farmers from three different counties in central Illinois. 
From these lots of seed, two selections of approximately 300 ears each 
were chosen on the basis of physical appearance. Ears included in the 
“good seed” selection had been grown on plants apparently not much 
affected by any of the root, stalk, and ear-rot diseases, while the ears 
included in the “susceptible seed” selection bore evidence of having 
been produced on diseased plants. No dead or weak-germinating ears 
were included. Data presented in Table XVI show that the corn grown 
from the susceptible seed selection was affected to a much greater extent, 
as expressed in terms of acre yield, by the inoculations with both C. 
acremonium and A . steward than was the corn grown from the good 
seed selection. Com grown from the susceptible seed selection also was 
more susceptible to injury following inoculation with G. saubinetii. 
