Fusarium Blight of the Soy Bean 
39 
determination was doubtful. The fact that these varieties were 
planted so late that hot, dry weather prevailed during a large 
part of their early growth explains why they were so rapidly 
forced to maturity. The Black Eyebrow variety remained free 
from disease thruout the season. An examination of plants in all 
parts of the field showed that the disease was abundantly and 
uniformly distributed. 
Since the Black Eyebrow variety, which was planted late in 
1916, i. e. June 8, remained free from the disease,, it was planted 
again at intervals in 1917 in order to observe the effect of seasonal 
planting on the development of the disease. The first planting 
was made on April 26, another on May 31, and a third on June 
21. The ground was hardly suitable for planting between these 
dates. Plants from the second and third planting were much 
dwarfed because of unfavorable weather, severe nematode infec- 
tion, and a lack of cultivation, and for this reason no certain 
results as to the amount of infection in the different plantings 
were obtained. The most important determination possible from * 
these observations is that some other variety more suitable to 
late planting should be used in future tests for this purpose. 
Since the Black Eyebrow variety remained free from the disease 
in 1916, it is important to note that a few diseased plants of this 
variety were found in the general variety test rows referred to 
below where the seed were planted earlier. However, the variety 
seems to show some evidence of resistance. 
A larger number of varieties were tested in this field in 1917. 
Three rows each of the following varieties were planted on April 
I 26: Brown, Black Eyebrow, Virginia, Mammoth Yellow, Early 
Dwarf Green, Wilson Black, Barchet, Jet, Austin, Arlington, 
Guelph, Chiquita, Auburn, Manchu, Tokio, Peking, Tar Heel 
Black, Haberlandt, and Medium Yellow. Every tenth row was 
planted to Clay cowpeas, and one row of the One Hundred Day 
Speckle velvet bean (Mucuna utilis ) was planted around two sides 
of the field. By July 20 the disease was abundant in all of the 
varieties of soy beans except the Black Eyebrow discussed above. 
The cowpeas were so badly diseased that all died before blooming. 
The velvet beans were entirely free from nematodes or Fusarium. 
The Brown variety, altho as badly infected by the nematode 
and Fusarium as any of the other varieties, deserves special men- 
tion because of its tolerance to these parasites. In spite of the 
presence of a large number of nematode galls, varying in diameter 
from 1 to 15 mm., and the presence of Fusarium thruout the xylem 
area of the roots and for some distance up the stem, there was 
' absolutely no wilting, no chlorosis, nor any external evidence of 
any infection whatsoever. The plants were from four and one- 
