1916] 
GILMAN—CABBAGE YELLOWS TX 
TABLE XII 
SUMMARY OF RESULTS OF EXPERIMENTS TO SHOW THE RELATION 
TEMPERATURE TO ATTACK OF THE FUNGUS 
Extent of trial 
Approximate 
Incu- average temperature | Condition 
bation Infected soil Uninfected soil іп °С. of control 
„period at incep- 
in days | Higher | Lower | Higher | Lower tion of 
temper- | temper- | temper- | temper- disease 
ature ature ature ature Higher Lower 
13 3 flats.| 1 flat 1 flat 1 flat 22° 16-20° | Healthy.. 
21 1 flat 1 flat 1 pot 1 pot 22° 16-20? | Healthy*. 
30 10 pots.| 12 pots.| 1 pot 1 pot 14-16? | Healthy.. 
4 20 pots.| 20 pots.| 3 pots.| 3 pots.| 22-24? 16° | Healthy”. 
23 3 flat fl lebar. [2 flat... 4-18? | Healthy.. 
12 3 flats.| 1 flat wat...) 2 Gat... 25° 4-18° | Healthy.. 
12 7 pots.| 5 pots.| 2 pots.| 2 pots. 25° 4-18° | Healthy.. 
8 2 flats flat..| 2 pots.| 2 pots. 25^ 4-16? | Healthy.. 
10 З flats.| З flats.| 2 pots.| 2 pots. 30° |4-16° | Healthy*. 
*In these cases the controls in infected soil at the lower temperatures became 
diseased later, due to a rise of temperature above the point at which they were able 
to resist the disease. 
In a further experiment seeds were planted on October 20 
in pots of infected soil and allowed to stay in the green- 
house. The soil temperature was 10-16°С., and while a little 
disease appeared from time to time after December 1, 1914, 
the attack was very light and very few of the plants suf- 
fered. When on February 2, five pots of these plants were 
taken to a greenhouse whose air temperature was 28-30°C., 
yellows appeared in virulent form in three days and all but 
three plants were dead on February 20. Plate 1, fig. 3, shows 
typical pots from this experiment. It was repeated February 
28 with similar results. 
The fact that high temperatures caused the yellowing of the 
cabbage when the plant was attacked by F. conglutinans hav- 
ing been clearly established, the next point was to find, if pos- 
sible, whether the fungus entered the host at the lower temper- 
ature or not. The first experiments were made by plating 
from the plants in the lower temperatures, especially from 
parts of the roots of plants grown in infected soil. Although 
the plates were made in the same manner and with the same 
