Mar. ia, 1917 
Fusarium-Blight of the Soybean 
437 
Experiment VII.—On May 25, 1916, two ioo-foot rows of each of 
the soybean varieties Tokio, Haberlandt, Mammoth Yellow, Medium 
Yellow, and Virginia were planted in a field which produced a large per¬ 
centage of wilt In cowpeas in 1914. Two rows of cowpeas were planted 
in the same plot. By September 1, when all the plants had fully ma¬ 
tured, a small percentage of wilted cowpeas had been noted; but no 
blighted soybeans were found. 
Similar data were obtained from observations on cowpeas and soy¬ 
beans grown in the experimental plot devoted to plant breeding. In 
this 4-acre plot, three or four rows of soybeans were alternated with 
three or four rows of cowpeas throughout the field. Some wilt occurred 
in practically every row of cowpeas in the plot, but careful examinations 
during the season failed to reveal a single soybean blighted with Fu- 
sarium sp. among 17 standard varieties and 50 other unnamed selections. 
Experiment VIII.—The field at Red Springs, N. C., in which at 
least 60 per cent of the Mammoth Yellow soybeans were blighted in 1915, 
was again planted with this variety on May 23, 1916. In a portion of 
the field which had been reserved for the purpose, one 54-meter row 
each of Haberlandt, Mammoth Yellow, Pekin, Black Eyebrow, Medium 
Yellow, and Tar Heel Black soybeans and a row of Clay cowpeas were 
planted on June 8. On August 10 the main field and all of the varieties 
in the test, including the cowpeas, showed considerable blight or wilt, 
except the Black Eyebrow and the Virginia varieties of soybeans. On 
August 26 the latter of these varieties was apparently free from disease, 
but the plants had declined with age to such an extent that the exact 
determination was doubtful. The Black Eyebrow variety, however, 
remained free from disease throughout the season. 
SUMMARY 
(1) A disease of soybeans not previously reported has been studied 
during the past two years. 
(2) The disease is characterized by a chlorosis and shedding of the 
leaves or leaflets, followed by the death of plants, and is herein called 
“blight or wilt.” 
(3) Soybean-blight has been observed in several localities within 
North Carolina on soils infected with cowpea-wilt. 
{4) A species of Eusarium belonging to the section Elegans is the 
causal organism. 
(5) Cultural and morphological studies which are regarded as of 
primary importance in distinguishing species of Fusarium show that 
the strain of Fusarium on soybean is identical with the organism pro¬ 
ducing the wilt of cowpeas. 
(6) Reciprocal inoculation experiments with the strains from soy¬ 
beans and cowpeas show that cross-inoculations can be made. These 
experiments were conducted in the greenhouse and under field condi- 
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