318 
JAMES GEERE DICKSON 
proteins. Since phosphorus and nitrogen enter into the chemical 
composition of compounds found in both foHage and fruit, a deficiency 
in either of these elements in the culture solution limits the total 
weight of the grain produced as well as the total dry weight of the 
plant. 
7 
CULTUftE SOLUTIONS 
Figure 4. Curves showing the average yield of grain by plants grown in the 
normal solution and in solutions with one nutrient element in each case reduced to 
one tenth normal. 
Table 7 
The Average Ratio of Grain to Straw and the Weight of the Individual Kernels Produced 
hy Plants Grown in Normal Solution and in Solutions with One Nutrient 
Element in Each Case Reduced to One Tenth Normal 
No. Det. 
per Year. 
Solution, Deficient 
Element Given 
Gram -^^ . ,. ^ 
Ratio (in Percentage) 
Straw 
Weights of Individual Kernels 
in Grams. 
1916 
1917 
Ave. 
1916 
1917 
Ave. 
4 
Normal 
75.3 
47.3 
22.7 
48.4 
.0204 
.0181 
.0092 
•0159 
2 
Mg o.i 
19.6 
.0081 
2 
Ca 0.1 
65.5 
38.6 
19-3 
41. 1 
.0198 
.0143 
.0089 
.0143 
2 
K o.i 
84-5 
55-4 
25.8 
55.2 
.0245 
.0175 
.0115 
.0178 
2 
P O.I 
71.9 
46.4 
31-5 
50.0 
.0238 
.0230 
.0101 
.0190 
2 
N 0.1 
79-3 
41.4 
33.1 
51.3 
.0253 
.0200 
.0186 
.0213 
