442 
Journal of Agricultural Research 
Vol. VIII, No. ia 
Table; I .—Crops grown on plots I to 4 from iqio to IQ16, inclusive 
Year. 
Plot 1 (con¬ 
tinuous 
planting). 
Plot 2 (rotation). 
Plot 3 (rotation). 
Plot 4 (rotation). 
1910 
Peanuts.... 
Peanuts. 
Cowpeas, fall pota¬ 
toes. 
Com,crimson clover. 
1911 
Corn, crimson 
clover. 
Peanuts. 
Cowpeas, fall pota¬ 
toes. 
1912 
.do. 
Cowpeas, fall pota¬ 
toes. 
Corn, crimson 
clover. 
Peanuts. 
1913 
Peanuts. 
Cowpeas, fall pota¬ 
toes. 
Com,crimson clover. 
1914 
Corn, crimson 
clover. 
Peanuts. 
Cowpeas, fall pota¬ 
toes. 
1915 
.do. 
Cowpeas, fall pota¬ 
toes. 
Corn, crimson 
clover. 
Peanuts. 
1916 
.do. 
Peanuts. 
Cowpeas, fall pota¬ 
toes. 
Com,crimson clover. 
From Mr. W. R. Beattie, formerly of the Office of Horticultural Inves¬ 
tigations of the United States Department of Agriculture, it was learned 
that peanut leafspot, caused by Cercospora personata , was the only disease 
observed during the years from 1910 to 1912. 
In 1913, a fresh supply of peanut seed of the Valencia variety was 
obtained from a concern in Norfolk which buys peanuts in large quantities 
from various States for making peanut butter and confections. The 
seed for each succeeding year was saved from peanuts grown on the 
experimental plots the previous year. 
It was learned that a few wilted peanut plants were observed in the 
1913 crop and that the number of diseased plants increased each year. 
In 1916, the writer planted in experimental plots 1 and 2 Valencia 
peanuts which were obtained from the Department of Agriculture. 
Some of these seeds were also planted in a plot near by which had not 
grown peanuts for at least several years. Over 15 per cent of the plants 
in the experimental plots wilted, while all of the plants in the plots 
near by remained healthy. These data, together with the observation of 
the wilted plants in 1913 and each succeeding year, lead the writer to 
conclude that the wilt-producing organism was not present in the soil 
previous to 1913, but had been introduced with the fresh supply of seed 
used that year. 
DESCRIPTION OF THE DISEASE 
Under field conditions in Virginia this peanut-wilt begins to show 
when the plants are between 1 and 2 months old and continues to develop 
on new plants, here and there, throughout the season. In some cases 
one or two shoots wilt, while the rest of the shoots appear healthy, but 
in the majority of cases the whole plant eventually wilts, as shown in 
Plate 96, A. Examination of the wilted shoots generally discloses 
coarse white mycelium and small brownish sclerotia about the size of 
