298 
Journal of Agricultural Research 
Vol. XI, No. 7 
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less of the gradation of temperature it had passed through in removal. 
It was evident that the method of removal had little or no effect upon the 
production of the disease, and further proof was obtained of the ability 
of the lower temperatures to inhibit the devel¬ 
opment of the scald phenomena after the diseased 
condition had actually been produced. 
Experiments were also made to determine the 
effect of fluctuating temperatures upon the devel¬ 
opment of scald. Palladine (16) found that 
sudden changes in temperature caused an in¬ 
crease in the amount of carbon dioxid given off 
by seedlings, but Blanc (1), on the other hand, 
has reported that when seedlings and plant parts 
were moved from one temperature to another 
the rate of respiration was a mean between the 
normal rates at the two temperatures. 
Grimes apples of the same lot as reported in 
figure 11 were placed in moist chambers and 
moved from one temperature to another at in¬ 
tervals of two days. In 
one case the apples were 
moved back and forth 
from 5 0 to 20°. The amount of scald devel¬ 
oped at the different times of recording was 
found to be slightly less than on similar apples at 
a constant temperature of 15 0 , and the moved 
apples “stood up” approximately the same length 
of time as those at 15 0 , both being discarded on 
November 6. 
In a similar experiment with apples of the same 
lot the moist chambers were moved back and forth 
from o° to 30°. The higher temperature was 
secured in a warm laboratory and not in a closed 
incubator. The apples developed no scald and 
“stood up” till November 20—as long as similar 
apples at a constant temperature of io°. Two 
reasons can be offered for the absence of scald, 
one that better aeration was secured by leaving 
the moist chambers in the open laboratory a part 
of the time and the other that, as has already been pointed out, storage 
at a temperature of 30° is unfavorable to the development of scald. The 
fact that the apples “stood up” well in storage would emphasize the first 
hypothesis. 
TEMPERATURE CENTIGRADE 
Fig. 14.—Graphs showing the 
effect of temperature on apple- 
scald at the end of 2, 3,4, 5, 6, 
7, 8, 9, 10, 15, and 17 weeks. 
The dotted graphs show the 
amount 3 days after removal 
from storage at the end of 
the given week. The apples 
were Grimes from the same 
orchard as those of figures 1a 
and 13, but were picked on 
September 21 and the exper¬ 
iment was started on Septem¬ 
ber 22. 
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TEMPERATURE CEN776RR0E 
Fig. 15.—Graphs sho'ttfing the 
effect of temperature on ap¬ 
ple-scald at the different 
temperatures at the end of 
4. 5» 6, 7. 9, 10, 13, and 15 
weeks. The dotted graph 
shows the amount of disease 
3 days after removal from 
storage at the end of the 
given week. The apples 
were Grimes of the same lot 
as those of figure n, but had 
been in commercial cold 
storage from September 9 to 
October 16. 
