Fiisarium in Tuber Rot and Wilt of Potato 
29 
these were added at the rate of 10 gm. per Hter. Potato extract 
medium was made up by extracting 500 gm. ground potato tuber 
with 500 cc. H./J, and then adding 500 cc. of the foregoing solution 
to the extract. 
A series of cultures (table II) was run at 12° C. and the amount 
of dry weight formed determined at 2 day intervals for 10 days. In 
this series the medium was at 12° C. at the time of inoculation. 
TABLE II 
Dry weight (in milligrams) in potato extract medium; temperature 12° C. 
Fusarium oxysporum 
Fusarium trichothecioides 
Number of days 
Number of days 
2 
4 
6 
8 
10 
2 
4 
6 
8 1 10 
I 
0.2 
0.6 
0.4 
0.4 
0.4 
0.4 
5.2 
5.6 
5.4 
13.2 
13.0 
13.1 
1.4 
1.8 
1.6 
4.0 
4.4 
4.2 
9.4 
12.2 
10.8 
27.0 
II 
' 44.6 
Average 

35.8 
Table III shows the growth by day intervals made for 10 days 
when levulose was used as the carbon source. The solutions 
were at the temperatures indicated at the time of inoculation. 
TABLE III 
Dry weight (in milligrams) formed by day intervals 
Fusarium trichothecioides at 25° C. 
Number of days 
1 
2 
3 
4 
t 
5 I 6 
7 
8 
9 ! 10 
I 
II 
Average 
0.2 
0.2 
0.2 
0.6 
2.4 
1.5 
4.2 
18.0 
11.1 
12.8 
31.6 
22.2 
29.0 
32.4 
30.7 
19.2 
34.2 
26.7 
25.4 
27.2 
26.3 
19.4 
41.9 
30.6 
34.0 i 43.6 
47.7 50.8 
40.8 ! 47.2 
Fusarium oxysporum at 25° C. 
Number of days 
1 
2 
3 
4 
5 
6 
7 
8 
9 j 10 
I 
II 
Average 
0.4 
0.8 
0.6 
1.8 
3.2 
2.5 
9.2 
10.8 
10.0 
16.0 
29.2 
22.6 
23.6 
33.4 
28.5 
19.6 
21.2 
20.4 
24.0 
27.5 
25.7 
24.1 
26.0 
25.0 
30.9 ; 37.0 
34.8 ; 38.8 
32.8 1 37.9 
