FUSARIUM BLIGHT OF THE SOY BEAN AND 
THE RELATION OF VARIOUS FACTORS 
TO INFECTION 
BY RICHARD O. CROMWELL 
Extension Plant Pathologist, 
Iowa State College^ 
During the siiinnier of 1915 and each succeeding summer, 
packages of diseased plants of the soy bean Soja max (L.) Piper 
( 20 ) 2 ' 3 were received at the North Carolina Experiment Station 
from several correspondents. A large number of plants in the fields 
from which these specimens were taken had become stunted or 
chlorotic, or were dead. The plants received were still green and 
in good condition for examination. The evidence obtained from 
a preliminary inspection indicated that the diseased condition 
was due to the presence of a fungus belonging to the genus 
Fusarium. Furthermore nearly all of the isolations from this 
material gave apparently pure cultures of a species of Fusarium. 
Because of the importance of legumes in the cropping systems 
of the Piedmont and Coastal Plains sections, and because of the 
seriousness and extent of Fusarium diseases of members of this 
and thirteen other plant families,'^ an investigation was outlined 
(1) to determine the parasitism of this species of Fusarium on 
soy bean, (2) to establish its relationship to Fusaria of the section 
Elegans in so far as a comparison of the cultural characters per- 
mitted, and (3) by means of cross inoculations and field studies 
to determine the relationship of this disease of soy beans to the 
wilt disease of cowpeas (Vigna sinensis Hassk.) caused by 
Fusarium tracheiphilum Smith. 
The results of these investigations up to the close of the sum- 
mer of 1916 have been reported by the writer (6). The studies 
were continued at the North Carolina Experiment Station until 
^Formerly assistant plant pathologist, North Carolina Experiment Station. The 
writer is indebted to the North Carolina Experiment Station for leave of absence in 
order that full time could be given to these studies. Submitted for publication June, 1918. 
^Reference is made by number to “Literature Cited,” pp. 
*Piper (20) gives the following as the full synonomy of the soy bean; 
Phaseolus max L. 
Dolichos soja L. 
Soja hispida Moench 
Soja japonica Savi 
Glycine soja Siebald and Zuccarini 
Soja angustifolia Miguel 
Glycine iissuriensis Regel and Maack 
Soja max (L.) Piper 
‘Wollenweber (31, p. 35) 
