522 
Journal of Agricultural Research 
Vol. XXIII, No. 7 
of its morphological structure, is very capable of offsetting root infec¬ 
tion without conspicuous external symptoms. 
It would hardly seem practical to resort to any means of removing 
the cap and then disinfecting for control of these rots of corn. Careful 
selection in the field and proper care in handling and storage along with 
germination tests should adequately eliminate the possibility of seed 
corn infection. The question of soil conditions, fertilization, rotation, 
and cultural methods should be given particular attention in order to 
reduce infection and secure strong initial growth. 
With further inoculation work duplicated under field conditions it 
is hoped to prove the points which have been discussed theoretically. 
In pointing out these possibilities it is hoped that other investigators 
will assist to determine such proof under their conditions. 
SUMMARY 
(1) Through an extensive survey of field seed corn in Delaware by 
means of cultural and germination studies at least four prevalent fun¬ 
gous parasites were determined. A brief survey of field com from 21 
other States indicates a similar prevalence of these organisms. 
(2) The following four parasites were consistently found in our 
studies: Cephalosporium sacchari Butler; Fusarium moniliforme Sheldon; 
Gibberella saubinetii (Mont.) Sacc. and Diplodia zeae (Schw.) Lev. The 
parasitism of these fungi has been determined by inoculations. 
(3) So far as we have been able to determine the fungus here referred to 
as Cephalosporium sacchari is reported for the first time as a parasite 
of com. Fusarium moniliforme is considered identical with Oospora 
verticilloides described on com in Italy by Saccardo. 
(4) Cultural studies of field com in Delaware show the following 
prevalence for these parasites: Cephalosporium sacchari , 39.54 per 
cent; Fusarium moniliforme , 19.92 per cent; Gibber ella saubinetii, 5.95 
per cent; Diplodia zeae , 5.69 per cent. 
(5) Inhibition of germination as the result of virulence by these 
parasites occurs in the following order under cultural and laboratory 
conditions, Diplodia zeae , Gibber ella saubinetii , Fusarium moniliforme , 
and Cephalosporium sacchari . 
(6) Species of the following genera of fungi have also been found 
established internal of com: Aspergillus, Cladosporium, Penicillium, 
Altemaria, Helminthosporium, Rhizopus, Spicaria, Hormodendrum, 
Torula, Chaetomium, Colletotrichum, and also several bacteria. These 
fungi are not considered in the same degree of importance as the above- 
mentioned parasites. It is probable they have become established as 
the result of unfavorable field and storage conditions. 
(7) The method by which these parasites are carried in the kernel 
was determined through cultural and histological studies. It was 
found that the parasites become established in the tissue of the cap and 
the cavity between the cap and dorsal point of the scutellum. In 
some instances the fungus works upward underneath the pericarp. 
Under certain favorable conditions not yet determined the fungus 
infects and destroys the embryo. 
(8) Seed disinfection has not proved successful because of the manner 
of internal infection. 
(9) No uniform symptoms to associate infection of field corn with 
these parasites can be consistently described. Various discolorations 
of the germ end of the kernel are found. These symptoms are always 
