JOURNAL OF MOTTO, RESEARCH 
Vol. VIII Washington, D. C., March 19, 1917 No. 12 
PEANUT-WILT CAUSED BY SCLEROTIUM ROLFSII 
By J. A. McCuntock, 
Plant Pathologist, Virginia Truck Experiment Station 
INTRODUCTION 
Wolf 1 records a fruitrot of peanuts (Arachis hypogaea) caused by 
Sclerotium Rolfsii Sacc., but states (p. 143) that “ usually there is no indica¬ 
tion of the disease in the appearance of the aboveground parts." During 
the summer of 1915 the writer observed wilted peanut plants on two 
plots of peanuts at the Virginia Truck Experiment Station, at Norfolk, 
Va. The associated organism was found to be S. Rolfsii , and its patho¬ 
genicity has been established. 
Observations are here presented on the life history of the causal organ¬ 
ism and experiments on control measures by the use of resistant varieties 
of peanuts during the season of 1915 and 1916. Data relative to the 
relation of 5 . Rolfsii to other crops used on the experimental plots are 
also given. 
HISTORY OF THE DISEASE 
In 1910 an experiment was started at the Virginia Truck Experiment 
Station to determine the value of rotation as compared with the continu¬ 
ous planting of peanuts. This experiment, which is still being conducted, 
occupies four adjoining plots, each about one-third of an acre in size. 
Plots 1 and 2 were planted to peanuts in 1910. The next year plots 
1 and 3 were planted to peanuts, while plots 2 and 4 were planted to the 
other crops used in the rotation. In 1912, plots 1 and 4 were in peanuts, 
the other two being planted to the other rotation crops. In 1913, the 
3-year rotation had been completed, so peanuts again occupied plots T 
and 2. 
The source of the peanut seed used in beginning this experiment was 
not known, but during the years 1911 and 1912 peanuts from the previous 
year's crop were used for seed. 
Table I shows the position of the four plots, with their respective 
crops for the years 1910 to 1916, inclusive. 
1 Wolf, E. A. Leaf spot and some fruit rots of peanut. Ala. Agr. Exp. Sta. Bui. 180, p. 127-150, 5 pi. 
1914. 
(441) 
Journal of Agricultural Research, 
Dept, of Agriculture, Washington, D. C. 
hn 
Vol. VIII, No. 12 
Mar. 19, 1917 
Key No. Va.—2 
