74 
Journal of Agricultural Research 
Vol. IX, No. 3 
Frank (2, p. 153) grew corn and peas with roots divided between two 
compartments, one of which contained calcium nitrate and the other of 
which did not. The only result reported was that roots in the compart¬ 
ment with nitrate made a much more luxuriant development of side roots. 
He describes the experiment as being similar to one of Miiller-Thurgau’s. 
Nobbe (9), growing corn in pots with fertilizer applied to different parts 
of the soil, also observed that the development of lateral roots was much 
greater in those zones where fertilizers had been applied. 
Faack (1) grew wheat with part of the roots in a solution lacking one 
element and a few roots in a solution containing the single salt not present 
in the main solution. He found that the plant would grow without marked 
disturbance under these conditions if the proper salt and proper concen¬ 
tration were used in the single salt solution. As only two plants per 
lot were used, his data do not show the extent to which growth and 
absorption were affected. 
METHOD OF EXPERIMENTS 
The experiments were carried out in water cultures, as it is obviously 
difficult to maintain a good separation of roots and localize the distribu¬ 
tion of salts iti sand cultures. Erlenmeyer flasks of “Nonsol” or Jena 
glass joined together at the necks were used as receptacles. The plants 
were grown with their roots divided between the two flasks, one of which 
contained a complete nutrient solution and the other a nutrient solution 
lacking one element. 
Rice seedlings were germinated over distilled water for Experiments I, 
III, and IV, but in tap water for subsequent experiments, as root devel¬ 
opment was better in tap water and there was no need of excluding all 
mineral salts before starting the experiment. Corn (Zea mays) was 
' germinated in sphagnum moss. One corn seedling or two rice seedlings 
were grown in each double flask. 
The compositions of the nutrient solutions used are shown in Table I. 
Table I —Composition of nutrient solutions used 
Solution. 
Complete 
acid 
solution. 
Complete 
neutral 
solution. 
Nitrogen- 
. free 
solution. 
Phos¬ 
phorus- 
free 
solution. 
Potassium nitrate (KN 0 3 ). 
Monopotassium phosphate (KH 2 P 0 4 ).... 
Dipotassium phosphate fK 2 HP 0 4 ). 
Monosodium phosphate (NaH 2 P 0 4 ). 
Gm. 
IO. 71 
7 - 
Gm. 
IO. 71 
3 - 57 
3 - 57 
Gm. 
3 - 57 
3 - 57 
Gm. 
10. 71 
■ 
Sodium nitrate (NaN 0 3 ). 
Sodium sulphate (Na^O^ ioH 2 0 ). 
Calcium chlorid ^CaCl 2 ' 6 H 2 0 )... 
Magnesium chlond (MgCl 2 ‘ 6 H 2 0 ). 
Potassium sulphate (K 2 S 0 4 ). 
21.43 
3-*5 
2. 00 
2. OO 
21. 43 
3*15 
2. OO 
2. OO 
3 * i 5 
37. 60 
35- 60 
12. 40 
21.43 
2 . OO 
2 . OO 
6. 20 
Calcium nitrate (Ca(N0 3 ) 2 "4H 2 0). 
Iron (Fe). 
. 80 
• 2 5 
.80 
. 80 
.80 
Sulphuric acid (H«SD 4 ). 
Distilled water. 
IOO, OOO c. c. 
Potas¬ 
sium- 
free 
solution. 
Gm. 
6. 30 
14. 30 
3 - 15 
2. OO 
21. 86 
. 80 
•25 
