504 
Journal of Agricultural Research 
Vol. XXIII, No. 7 
tural condition. He also reports finding a similar color on seed corn 
naturally sick with Oospora. This discoloration of the grains we have 
commonly observed with infected kernels overwintering under field 
conditions. Tiraboschi (35) gives more of a detailed study to this 
fungus, and his results and illustrations are very convincing. The 
confusion in the past regarding the identity of Fusarium moniliforme 
and Oospora verticilloides is no doubt the result of the macronconidia 
being overlooked. 
The symptoms on seed com produced by this fungus are numerous 
and more commonly found than those produced by any of the other 
internal parasites. The first conspicuous symptom is that of the typical 
kernel rot. Such infected kernels appear irregularly distributed in the 
ear as shown in Plate 12, D. This kernel rot in appearance agrees with 
the one described by Burrill and Barret (< 5 ) as caused by their Fusarium 3. 
The condition of such infected kernels is similar to Sheldon’s (29) 
description. The kernels appear slightly shrunken and light brown 
in color. Such kernels are soft and fragile, with the contents powdery, 
except for the embryos, which are discolored and shrunken. In some 
instances a slight development of mycelium and spores is found on the 
surface. Other symptoms of infected kernels are discolorations of the 
seed coat. These discolorations vary from a light brown to pink and 
lavender in color. They may be evident on any part of the kernel but 
are most commonly found near the germ end. This discoloration is the 
result of the development of mycelium between the integuments. These 
symptoms become more pronounced during germination because of the 
activity of the fungus. In some instances the fungus may spread from 
the germ end under the pericarp so as to discolor the lower half of the 
kernel. 
Several samples of bin-selected ears showed cracking of kernels just 
above the cap, as illustrated in Plate 12, B. This cracking would involve 
as many as 8 or ro adjacent kernels in a row. Such symptoms were 
found irregularly distributed throughout the ear. In the majority of 
such cases Fusarium moniliforme was found associated with such injury. 
The primary cause of this condition was not determined. The influence 
of excessive moisture and growth may have been the contributing 
factors. However, it would appear from all evidence that the fungus 
became established subsequent to the cracking. The embryo in these 
cracked kernels is frequently killed by the fungus. However, such 
seeds seldom develop into strong seedlings, owing to the amount of infec¬ 
tion! A series of 20 cracked and 20 normal-appearing kernels from the 
same ear were planted in the greenhouse. Only 9 of the cracked kernels 
developed, whereas perfect germination and development were secured 
with the ones not cracked. During germination, when the plants are 
6 to 8 inches high, it is found on removing the seedling that the seed 
coat is conspicuously discolored. The pericarp takes on a deep lavender 
color. 
On the germinator, infection first appears as a slight effused growth 
around the cap. As a rule, the fungus ramifies between the pericarp 
and epidermis, resulting in pronounced discoloration of the pericarp 
and involving the lower half of the kernel. Often the discoloration will 
appear as irregular streaks, extending from the germ end toward the 
crown. The germination of corn is inhibited by this fungus but not as 
severely as was observed with Gibberella saubinetii and Diplodia zeae. 
