570 
The Philippine Journal of Science 
1920 
root yields and the Ca/K-ratio values, high yields being obtained 
with the whole range of these values tested. 
The general conclusion which must be reached from these ex- 
periments is similar to that already stated by Gile, 51 by Totting- 
ham, and by Shive. The effect of a certain ratio between any 
two ions in a certain total concentration appears to depend upon 
the relation of these ions to all the other ions in the nutrient 
solution ; that is, upon* the complex balance of ions in the nu- 
trient solution. A certain optimum ratio may be found between 
two ions, as calcium and magnesium, for example, when a cer- 
tain balance exists between all the other ions present. But if 
this balance is altered, the optimum ratio between calcium and 
magnesium, for example, would be altered. 
Table 10. — Cation-ratio values for solutions of series I and II; for the en- 
tire series, and for solutions giving high and low and highest and lowest 
root yields. 
Mg/Ca. 
Mg/K. 
Ca/K. 
Series 
I. 
Series 
II. 
Series 
I. 
Series. 
II. 
Series 
I. 
Series 
II. 
Entire series: 
Minima __ 
0.21 
0.21 
0. 14 
0. 14 
0. 08 
0. 08 
Maxima 
13.43 
13. 43 
4. 68 
4.68 
2. 68 
2. 68 
Range . 
13.22 
13.22 
4. 54 
4.54 
2. 60 
2.60 
Low yields: 
Minima 
0. 64 
1.65 
0. 14 
0.14 
0.08 
0.08 
Maxima ... . 
13.43 
13. 43 
4.68 
4.68 
2.27 
0. 85 
Range 
12.89 
12. 78 
4.54 
4.54 
2. 19 
0.77 
High yields: 
* 
Minima 
0. 31 
0.21 
0. 14 
0. 19 
0.08 
0. 17 
Maxima -- _ 
6.48 
1.75 
0.75 
0. 80 
2.68 
2. 68 
Range. . 
5.17 
1. 54 
0. 61 
0. 61 
2. 60 
2. 61 
Highest yields 
0.53 
0. 45 
0. 19 
0.20 
0.35 
0. 46 
Lowest yields..- 
1.02 
13.43 
1.91 
4.68 
1.88 
0.35 
Water absorption . — Cultures T3R1C5 and T3R3C3 absorbed 
the greatest quantities of water in this series ; the latter culture 
also absorbed the most in series I. This series agrees with se- 
ries I in the culture showing lowest water absorption (T1R1C1) . 
In a general way, also, there is an agreement between the two se- 
ries in the direct relationship shown between dry yields of tops 
and roots, on the one hand, and water absorption on the other. 
Water requirement . — The results of this series disagreed with 
those of the preceding one in the exact proportions giving high- 
61 Gile, P. L., Lime-magnesia ratio as influenced by concentration, Bull. 
Porto Rico Agric. Exp. Sta. 12 (1912). 
