140 
AMERICAN JOURNAL OF BOTANY 
IVol. io, 
The results of this experiment were in line with those secured previously, 
and, when considered in connection with the preceding work, make possible 
the following conclusions: 
1. Plants growing very rapidly as a result of optimum moisture con¬ 
ditions for vegetative growth are most susceptible to the wilt. 
2. Moisture shortage that checks the growth of the host plant checks 
the development of the wilt also, and the longer and more severe the period 
of drought, the more the disease is inhibited. 
3. Plants growing in saturated soil are never attacked by the wilt disease. 
The Relation of Soil Moisture to the Growth of 
Uninoculated Plants 
Check series, consisting of plants grown in inoculated soil, were run with 
experiments I, II, and III. The data from check series III only will be con¬ 
sidered here, as they are the fullest. This series consisted of single crocks, 
each containing two plants which were carried at the different soil moistures 
for a period of seven weeks with an air temperature of approximately 28° C. 
The data given in tables 7 and 8 were taken at the conclusion of the 
experiment. 
Table 7 
Soil 
Weight of Tops Produced 
Moisture, 
Percent 
Wet Weight, 
Grams 
Dry Weight, 
Grams 
Percentage Dry 
Weight 
14-16. 
14.7 
2.4 
16.3 
16-18. 
23-5 
3 -i 
I 3 -I 
19-21. 
75 
9-6 
12.8 
23-25.. 
102 
H -37 
11.1 
31-33 ... 
146 
15.6 
10.6 
35 (saturation).. 
157 
2 
12.1 
Table 8 
Microchemical Analysis of Stem 
Soil 
Moisture, 
Percent 
Tip of Plant 
Base of Plant 
Tap Root 
Nitrate 
Sugar 
Starch 
Nitrate 
Sugar 
Starch 
Nitrate 
Sugar 
Starch 
14-16. 
2 
2 
2 
2.0 
2 
2 
2 
2 
1 
16-18. 
2 
3 
2 
2-5 
2 
2 
2 
, 2 
1 
19-21. 
2-5 
5 
2 
3 
5 
2 
2-5 
2 
1 
23-25.. • • • 
3 
5 
2 
5 
5 
i -5 
2-5 
5 
1 
31-33 . 
2 
5 
2 
3 
3 
2 
2-5 
2 
1 
35 (saturation) . . 
1 
3 
i -5 
1 
5 
i -5 
i -5 
2 
1 
1, absent. 2, slight. 3, moderate. 4, abundant. 5, very abundant. 
From these data it can be seen that the disease-resistant low-moisture 
