200 
Journal of Agricultural Research 
Vol. V, No. s 
Butler County, and in Dutchess County, N. Y. To judge from corre¬ 
spondence with growers it is a field rot and a storage rot of considerable 
importance. Infected tubers placed in storage rot badly the following 
spring; some of the growers are reported to have lost 50 per cent from 
dry-rot. Whether unaided F. eumarlii produces a wilt and a rot as a 
result of planting infected seed is not known. More likely it is secondary 
to infection by F. oxysporum or Verticillium albo-atrum in such cases. 
INOCULATION OF POTATO TUBERS WITH FUSARIUM EUMARTn 
F. eumartii 2932; isolated on January 3, 1914, from a stem-end dry- 
rotting tuber (Heath's Medium-Late Surprise variety) from Tower City, 
Pa. Culture used, 7-day old pionnotes on cotton stem. 
F. eumartii 2947; isolated as above on January 15, 1914. Culture 
used, 7-day-old pionnotes on potato cylinder. 
F. eumartii 3040; reisolation of 2947, April 23, 1914, from rotting 
Idaho Rural potato, 19 days after inoculation at 23.1 0 C. Cultures 
used, 22-day-old pionnotes on potato cylinder, and in a subsequent trial 
2-months-old cultures on rice, MelUotus alba, and cotton stems. 
F. eumartii 2958; isolated on January 28, 1914, as recorded in Nos. 
2932 and 2947. Culture used, 7-day-old pionnotes on potato cylinder. 
All tubers of the five varieties mentioned which were inoculated with 
the several original and reisolated strains of this species of Fusarium 
showed a progressive rot beginning at the points of inoculation in each 
case; many of the lenticels were invaded, sunken, and with the subjacent 
parenchyma browned. People's variety was the most susceptible, the 
others being affected in the order named—Early Rose, Jersey Peachblow, 
Netted Gem, and Idaho Rural (PI. XIX). However, even in the last- 
mentioned variety there was 100 per cent of infection about the inoculation 
pricks and lenticel invasion of all tubers. Some of the inoculated tubers 
were completely softened; others showed a dark-brown zone about the inoc¬ 
ulation prick, surrounded by an extensive watery zone of softened tissue. 
At low temperatures a typical slow dry-rot was produced. The respec¬ 
tive organisms were recovered in every attempt made: Nos. 2932 and 
2947 from all varieties used; 2958 from the Idaho Rurals; 3040 in first 
trial, one reisolation from the Idaho Rurals, and one from the Netted 
Gems; in a later experiment five reisolations were made from the Idaho 
Rural variety. 
Table V gives the results of the inoculations with F. eumartii . 
