444 
Journal of Agricultural Research 
Vol. VIII, No. 12 
some plated sections of wilted shoots, but none of these had white 
mycelium, and all failed to produce the brownish sclerotia. 
Healthy peanut plants of various ages were inoculated by placing pure 
cultures of the various fungi in contact with normal and with wounded 
stems just below the surface of the soil. Similar plants were labeled to 
serve as checks. The plants inoculated with the white mycelium and 
sclerotia began to wilt within a period varying from 15 days to 2 months 
after inoculation, while the control plants remained healthy. White 
mycelium and brownish sclerotia developed at the base of artificially 
infected plants. The causal organism was reisolated from the wilted 
stems and found to be the same as the original isolations. Plants inocu¬ 
lated with various other fungi isolated from diseased peanut shoots 
remained healthy. 
Isolations of the causal organism were made from time to time dur¬ 
ing the seasons of 1915 and 1916, and the fungus producing the coarse 
white mycelium and brownish sclerotia was found to be constantly 
associated with the wilted peanut shoots. 
The appearance of the peanut-wilt fungus corresponded so closely 
to descriptions of 5 . Rolfsii that the writer tentatively identified the 
fungus as this organism, although he had not seen any report of this 
fungus being found in Virginia. The fact that Wolf 1 had, in 1914, 
reported 5 . Rolfsii as being the cause of a fruitrot of peanuts in Ala¬ 
bama added weight to the writer's suspicion that the peanut-wilt 
organism found in Virginia is 5 . Rolfsii. During the winter of 1915-16 
cultures of the peanut-wilt organism were compared with stock cultures 
of 5 . Rolfsii from two authentic sources, and the organisms were found 
to be identical as regards mycelial development, and the size, shape, 
and color of the sclerotia, thus indicating that this peanut-wilt fungus 
is 5 . Rolfsii. In January, 1916, the opportunity was afforded the 
writer to examine specimens of peanut stems infected with S. Rolfsii 
which had been collected at Lykesland, S. C., in 1909 by Dr. W. A. 
Orton, of the United States Department of Agriculture. They were 
similar to specimens collected in Virginia by the writer during the season 
of 1915 and convinced him that the Virginia peanut-wilt is caused by 
5 . Rolfsii. 
IMPORTANCE OF SEED AS A MEANS OF SPREADING SCLEROTIUM 
ROLFSII 
Having observed that peanut pods from diseased plants bore myce¬ 
lium and sclerotia of 5 . Rolfsii both externally and internally, the writer 
deemed it advisable to test the importance of seed and its accompany¬ 
ing trash as a means of transmitting the peanut-wilt fungus. 
Seed for the bulk of the 1916 planting was hand-shelled from the 1915 
crop by laborers who made no attempt to discriminate between good 
1 Wolf, F. A. Op.cit. 
