Fusariiim in Tuber Rot and Wilt of Potato 
15 
tardy in coming up. Fiisariiim spp. were isolated from such les- 
ions. These lesions are identical in appearance with lesions found 
on potato stems and roots in the field which often are designated as 
"foot disease" and ascribed to the activity of Rhizoctonia. Late 
in Mav other series were started and the soil was infected with rice 
and spore suspensions. Xo infections resulted at all. even though 
the inoculum was derived from the same source as that used m 
earlier experiments. 
On [March 12, sprouts that were just breaking through the 
o^round were uncovered and smeared with rice infected either with 
p. osxspontm or with P. trichothecioidcs, 6 sprouts being used in 
each set. The plants were wounded no more than was inevitable 
in removing the soil. The soil was then replaced. The soil in the 
controls was remo\ ed in the same way, but no inoculum was r.pplied. 
The 12 sprouts to which inoculum had been applied were killed, 
while the controls remained healthy. There was no spreading 
of the disease to other sprouts, even where an abundance of 
inoculum was applied. 
The afi:ected sprouts reminded one forcibly of affected sprouts 
in potato fields in the spring. Here and there in the fields one 
finds sprouts that look sickly and small, which usually wilt and die 
or remain sickly and small. Upon examination of such sprouts, 
prominent brownish, watery lesions are found. At times such 
sprouts overcome the trouble and make a fair growth, at least 
until transpiration becomes excessive. These lesions also account 
for many of the "poor stands'" or failures of potatoes to come 
up evenly. If one digs in where a sprout ought to have come up, 
one can often find a tuber that has sprouted, but whose sprouts 
have been cut off entirely by such lesions. Often lateral buds 
develop into branches on such decapitated sprouts, only to be cut 
off again. If such a tuber finally manages to get a shoot above the 
ground, the shoot is sickly and backward. In 1912, 1913, and 1914 
the writer plated the inner tissue of many such sprouts and almost 
invariably obtained cultures of various Piisariiim spp., although 
often associated with Rhizoctonia and bacteria. Infection experi- 
ments conducted with Rhizoctonia in 1912-1913 gave almost uni- 
formly negative results. The writer was at first inclined to refer 
