bo 
the same worker (1926). Massey classt- 
fied the organism as Fusarium oxysporum 
Schlecht. emend. Wr. var. gladioli n. var. 
McCulloch (1944) considered the Fu- 
sarium she found associated with the vas- 
cular form of the disease to be sufficiently 
distinct from Fusarium oxysporum var. 
gladioli, described by Massey, to warrant 
putting it in another species. She classified 
it as Fusarium orthoceras App. et Wr. var. 
gladioli. In comparing the two organisms 
she stated, “In culture the bulb-rot organ- 
ism has. in most tests and examinations, 
shown less abundant aerial growth, less 
pigment, and wider macrospores than the 
.. The most distinctive 
characteristics of these two Fusaria of 
g'adiolus are the effects on the host.” 
Other workers have been inconsistent in 
yellows organism. . 
ILttiNors NATURAL History SURVEY BULLETIN 
Vol. 26, Art. 6 
their use of names for the causal agents of 
the different forms of the disease. Me- 
Clellan (1945) used the name Fusarium 
orthoceras App. & Wr. var. gladioli Mc- 
Culloch for the vascular Fusarium of glad- 
iolus. In a later article the same writer 
(1947) listed F. oxysporum f. gladioli 
Sny. & Hans. as the causal agent for yel- 
lows and rot. He described the other 
forms of the disease but did not name the 
causal agents. McClellan & Stuart (1947) 
used the name F. oxysporum f. gladioli 
(Massey) Sny. & Hans. for the causal 
agent of gladiolus ‘‘yellows, or corm rot.” 
McClellan (1948) used both names, F. 
oxysporum var. gladioli Massey and F. or- 
thoceras var. gladioli McCulloch. Nelson 
(1948) listed F. orthoceras Woll. var. 
gladioli McCull. as the cause of yellows, 
Fig. 4.—Sectioned corms of gladiolus variety Dieppe, in upper two rows, and Golden 
Arrow, in lower two rows, showing symptoms of all three forms of the Fusarium disease. The 
second corm from the left in the top row shows core rot and vascular discoloration. The first 
and third corms in the second row and the fourth corm in the top row show symptoms interme- 
diate between basal dry rot and core rot. The first corms in the third and fourth rows have 
basal dry rot. The other corms show the brown rot form of the Fusarium disease. 
