123 
Jan, 13,1923 
Respiration of Apple Seeds 
external conditions. They are also greater for C0 2 production than for 
oxygen consumption, greater when changingfrom 19 0 to 30° C., than when 
the reverse change is made, and greater at low temperatures than at 
higher temperatures. The differences in temperature coefficients, when 
the reciprocal changes 19 0 to 30° and 30° to 19 0 are made, suggest a stim¬ 
ulating effect of the higher temperature, which is not entirely lost upon 
return to the lower temperature. 
Upon removal of the inner coats and the onset of rapid germination, 
with vigorous respiration, the temperature coefficients remained about 
the same as for the same temperature interval with dormant seeds. 
Table III .—Temperature coefficients (Q 10 ) for the respiration of dormant apple seeds 
with outer coats removed 
Temperature interval. 
Qi# for oxygen 
consumption. 
Qit for CO2 
production. 
°C, 
A 1 
B 3 
A 1 
B* 
19 to 30. 
2.08 
i -73 
2.20 
I.90 
30 to 19... 
1.43 
1.03 
1.71 
1.14 
19 to 30. 
I.89 
i -43 
2.12 
i *35 
30 to 19. 
I.32 
1.07 
1.09 
19 to 10 . 
2.32 
i *35 
2.46 
i -53 
10 to O . 
3-63 
2.53 
11.04 
3.60 
0 to 13. 
3-03 
2.21 
7.66 
3* I 5 
13 to 30.... 
1,70 
i -59 
1.85 
2.07 
30 to 19 naked germinating embryos. 
i *95 
1.78 
2.07 
1.76 
1 Lot A was previously incubated under germination conditions at 2o°C., 50 days in intact condition, then 
68 days with outer coats removed. 
* Lot B was previously incubated under germination conditions, 5° days at 3o°C. in intact condition, then 
68 days at 20 0 to 30 0 with outer coats removed. 
Third experiment.— Newtown Pippin seeds. Fruit stored at o° C. 
to May 7, seeds removed during next few days and incubated under 
germination conditions at 5 0 to io° for 13 to 18 days. Many seeds had 
germinated. Only those not germinated were used for the respiration 
experiment. Fifty seeds in each lot at beginning of experiment. Some 
discarded from time to time on account of advancing germination or to 
keep a convenient number in a given condition for a given apparatus. 
(Table IV.) 
The principal points to be noted regarding this experiment are: 
1. The respiratory intensity which was about the same at the beginning 
of the experiment as shown in Table I, rose sharply with the onset of germi¬ 
nation, but fell somewhat after germination, with the second period at 
the excessively high temperature of 30° C. 
2. The respiratory quotient was high, as in the previous experiments, 
during incipient germination. The value of the respiratory quotient in 
this case reached 1.2, recalling Gerber’s observations. 5 
3. The respiratory quotient fell in value as respiratory intensity 
increased with advancing germination. The lowest value of the respira¬ 
tory quotient, as well as the figures expressing respiratory intensity during 
the same period, are here almost identical with those for the period of 
greatest respiratory intensity in Table I. 
6 See discussion on page 119 
