Apr 7,1923 Nutrition of Plants as an Electrical Phenomenon 
45 
It will be seen by referring to Table II and figure 3 that the absorp¬ 
tion of plant food for i hour per day, and other fractional parts, is out 
of proportion to what might be expected if time alone governed absorp¬ 
tion. For example, subtracting the amount of potash in the original 
seed, or in the control, from the analysis of the plants grown i hour a 
day in the nutrient solution, we get 0.0520 gm. of potash actually 
absorbed by the plants during that time. In the same way by subtract¬ 
ing the control from those grown 24 hours a day in the nutrient solution. 
Fig. 3. —Graph illustrating the absorption of plant foods by wheat seedlings when grown for fractional 
parts of the day for lo days in nutrient solutions. 
we get only 0.2157 gm. of potash actually absorbed in 24 hours. If 
the rate of absorption of the plants kept in the nutrient solution i hour 
a day had been maintained in the plants kept in 24 hours a day, we 
would have had an absorption of 1.248 gm. instead of 0.2157 gm. In 
other words, we get over five times as much potash absorbed in the 
I-hour periods as might be exjpected if time alone governed absorption. 
This phenomenon is true with other plant foods; the curves rise very 
abruptly from the start and flatten out as the time increases.. The 
demand or desire for food seems to accumulate until the food becomes 
available; then an abnormal rate of absorption takes place. The figures, 
when plotted, are represented in figure 3. 
