506 
Journal of Agricultural Research 
Vol. XXIII, No. 7 
A study of diseased kernels in cross section has shown the fungus well 
established between the aleurone layer and integuments. Immature 
pycnidia have been observed in this region. The mycelium ramifies 
through the endosperm tissue. The starch grains appear corroded, as 
reported by Heald, Wilcox, and Pool (16). Rotted kernels present the 
same physical condition as that described for Fusarium moniliforme. 
Kernels which appear normal but show infection during germination 
often produce black streaks at the germ end. This appearance results 
from developing and progressing of the fungus under the pericarp. An 
interlaced mass of brown mycelium is often found developing under the 
pericarp. The most conspicuous sign is found during germination with 
the effused growth of white, cottony mycelium at the germ end. Germi¬ 
nation is greatly retarded and often inhibited as a result of infection. A 
summary of extensive germination tests shows that this fungus is more 
inhibitive to germination than the other parasites described. 
The white, cottony effused growth of this fungus in agar cultures 
is easily determined. The mycelium on the substratum takes on a 
brownish appearance with age. On rice agar it fruits abundantly. The 
conidia (pycnospores) are 2-celled and brown in color. Measurements 
of conidia from infected roots and cultures are the same. Conidia from 
rice media measure 16.5 to 31.5 ^ by 5 to 6 
PREVALENCE 
In making a survey of fungi internal of corn in Delaware an appeal 
was made to several hundred farmers, including many members of the 
State Corn Growers’ Association, requesting at least four ears of seed 
corn, two of which should represent the best seed com grown and two 
ears much above the average from bin selection; the object of making 
a request of this nature was to secure material from which first-hand 
information could be obtained on the amount of internal infection 
carried in seed com and to learn whether field selection was superior 
to bin selection. In order to make a comparison with other States a 
request for cooperation was sent to pathologists and agronomists of 20 
States of the corn belt. 
A careful review of Table I indicates that there are at least four species 
of fungi commonly found internal of seed com which are widely dis¬ 
tributed. We fully realize that the survey if not extensive enough to 
show the condition prevailing in seed corn in the several districts through¬ 
out the United States. Superficially the survey shows that the organ¬ 
isms vary in prevalence considerably throughout the different sections. 
Cephalosporium sacchari , Fusarium moniliforme, and Diplodia zeae seem 
to have a wide range but are probably more prevalent through the 
middle tier of States and the southern States, whereas Gibberella sau- 
binetii appears more prevalent through the States producing winter 
wheat. 
In North Dakota, from which 25 samples were received out of which 
375 kernels were cultured, no Cephalosporium sacchari or Gibberella 
saubinetii was found and only a trace of Fusarium moniliforme and 
Diplodia zeae . The samples from several or the States were not rep¬ 
resentative farm samples but were sent as special selections from ex¬ 
periment stations. 
