Fusarliim Blight of the Soy Bean 23 
MORPHOLOGICAL AND CULTURAL COMPARISON OF THE 
FUSARIUM SP. ON SOY BEAN WITH F. TRACH El PH I LU M 
Since the studies summarized in Table 1 do not succeed in 
distinguishing- the species of Fiisariinn on soy bean and cowpea, 
a more extensive cultural study of these two fungi was made. 
For this purpose three series of cultures were grown, and the 
results have been summarized in Table 2. Each series contained 
10 cultures of each fungus on stem plugs, potato plugs, steamed 
rice, standard nutrient agar (1.8 per cent agar, 1.0 per cent acid), 
string-bean hard glucose agar (3 per cent agar, 1.0 per cent acid, 
and 10 per cent glucose), and oat hard agar (3 per cent agar and 
1.0 per cent acid). The cultures were examined when they were 
8, 15, 30, 50, and 75 days old. 
Table 2. — A inor photo ej leal eomparison of the species of 
Fusarium on soy hean and coiopea. 
F usarium sjy> on soy hean. 
1 
Medium I Macro- 
I conidia 
Sporodochia 
1 
1 Sclerotia 
1 
Color of 
mycelium 
Character 
of mycelium 
Standard 
nutrient 
agar 
No measure- 
ments 
Salmon- 
colored 
None 
White 
Mostly aerial 
and floccose, 
becoming ap- 
pressed in 
old age. 
String-bean 
agar 
do 
Salmon- 
colored; 
generally 
present 
Green 
do 
do 
Oat, hard 
glucose 
agar 
26.6 to 38.6 
by 3.69 to 
4.92 50 
days old 
Flesh- 
colored j 
Dark-green 
1 
Mostly lilac; 
some dark 
purple 
Cottony. 
Steamed rice 
Reds, pinks, 
lilacs, 
purples 
i 
1 
Potato plugs 
Normal 
spores 
absent 
Salmon- 
colored; 
generally 
present on 
sclerotia 
Dark-green 
Green, near 
sclerotia 
Floccose. 
Stem plugs. 
22.5 to 43.6 
by 2.87 to 
4.11 14| 
days old 
Salmon- 
colored; 
1 small 
i 
Green, very 
small; 
numerous 
White, _ 
sometimes 
green near 
sclerotia 
Floccose; 
scant. 
