12 
BULLETIN 818, U. S. DEPARTMENT OF AGRICULTURE. 
Table IV. — Soil disinfection tests with tomato and lettuce plants grownin 8-inch pots, 
with hot-water treatment, in May and June, 1918. 
[Two kinds of soil were used: Soil A was nematode and fungus infested; B was uninoculated fresh green- 
house soil.] 
Number 1 Hoot infection on June 12 
Plant notes, May 28. 
of plants 
(end of experiment). 
Kind of plants, soil used, and treatment 
. 
Nematode. 
Rhizoc- 
of soil-filled pots. 
3 
>> 
2 
Height 
a 
,2 
j^ 
>~ -J 
, 
Disease. 
6 
o 
c3 
a 
g 
> 
2 
11 
(inches). 
P4 
o 
o 
m 
3 
u 
Oh 
?! 
pS 03 
Tomato plants: 
Soil A— 
Boiling water poured into pots— 
| 1 
67 
66 

2 
15 
23 
i 
1.5 
4 to 44- 
1 
2,000 c. c 
2 
73 
70 

2 
20 
27 


4 to 44 
yxone. 1 
[3 
64 
65 


35 
54 
3 
4 
4| 
1 
1 
65 
64 






4 to 44. 
] 
3,000 c. c 
2 
70 
66 
o 



o 
o 
o 
44 
4| 
I Do.i 
3 
85 
71 





1 
70 
55 






34 
4,000 c. c 
2 
56 
57 




1 
2 
34 \ Do. 1 
.3 
49 
45 






4 
1 
72 
40 
16 
7 
17 
100 
40 
100 
2 to 3 
( 2 ) ( 3 ) 
Check (soaked with cold water). 
2 
50 
22 
17 
3 
1 
95 
20 
90 
li to 2 
( 4 ) ( 5 ) 
.3 
57 
42 26 
10 
4 
95 
40 
95 
2 to 24 
( 2 ) ( 3 ) 
Soil B— 
■ 
Boiling water poured into pots— 
1 
87 
48 






44 to 5 1 
2,000 c. c 
2 
56 
54 




1 
2 
4 
^None. 1 
3 
60 
52 




1 
2 
34 
1 
1 
60 
68 






5 to 54 
1 
3,000 c. c ; 
2 
60 
63 
73 
61 
o 


o 
o 
o 


6 to 6J 
4 to 44 
I Do. 1 
3 




1 
57 
52 




1 
2 
4§ to 5" 
1 
4,000 c. c 
2 
48 
54 
48 
51 




o 
o 




\ Do. 1 
3 


6 
1 
49 
30 


2 
7 
20 
66 
14 
( 6 ) ( 7 ) 
2 
32 
31 


18 
58 
27 
87 
4 to 5 
( 7 ) ( 8 ) 
Check (soaked with cold water) . 
3 
i 
40 
45 
38 
22 

14 

7 
5 
1 
13 
100 
16 
22 
42 
100 
3 to 4 
4 
( 6 ) ( 7 ) 
( 7 ) ( 3 ) 
5 
43 
44 


22 
50 
15 
34 
4 
( 7 ) ( 8 ) 
, 6 
42 
47 


17 
36 
4 
9 
2 
( 7 ) ( 8 ) 
Lettuce plants: 
Soil ,4— 
Boiling water poured into pots— 
j 1 
77 
60 

1 
13 
23 


3 to 3i } 
2,000 c. c. 
1 2 
63 
73 
o 


13 
18 
o 
o 
3 to 4 
J-Xone. 
l§ 
50 
31 

2 
6 
3 
10 
3 
l i 
45 
47 






3 to 34 
1 
3,000c. c 
2 
66 
52 






. 3 to 34 
y Do. 
■8 
64 
52 






34 
I 1 
40 
48 






24 to 3" 11 
4,000 c. c 
1 2 
43 
38 
o 
o 
o 
o 
1 
2.5 
24 to 3 7 Do. 
I 3 
37 
30 






" 3 | 
| 1 
45 
13 
12 
1 

100 
10 
77 
2 
( 9 ) 
Check (soaked with cold water) . 
2 
30 
22 
20 
1 
1 
100 
1 
4 
1 to 14 
}( 10 ) 
1 3 
43 
26 
21 
4 

95 
12 
46 
2 
Soil B- 
Boiling water poured into pots— 
1 
71 
37 




1 
3 
H 
2,000 c. c 
2 
3 
77 
55 
35 
46 








3 

9 

3 
3 
•None. 
1 
63 
51 






34 
3,000 c. c ! 
2 
3 
66 
49 
62 
47 







I 


4 to 44 
3" 
- Do. 
1 
40 
43 





34 
4,000 c. c 
2 
55 
34 





3£ to 4" 
• Do. 
3 
59 
34 





4 
1 
45 
44 


8 
IS 5 
11 
2 
2 
32 
23 


2 
9 23 
100 
3 
Check (soaked with cold water). 
3 
1 
30 
33 
30 
23 

20 

3 
5 

17 
100 5 

22 
3 
34 
Do. 
5 
16 
13 


7 
54 4 
31 
2 
6 47 
31 


7 
22 

n 
1 Plants vigorous. 3 Nematode stem galls, many. & Nematode stem galls, 'few. 
s Damped-off , few. * Damped-off , many. 6 Damped-off, 1. 
7 Nematode stem galls, none. 9 Several plants damped-off and some with stem galls, 
8 Damped-afij none. 10 No damping-off , but several plants with stem galls. 
