Potassium to Growth in Plants. 
221 
added after three days were very. similar : four nodes had developed, the 
ultimate leaves were unfolding, and the flowers were showing colour. The 
plants growing in the solution to which potassium was added after six 
days were smaller than those growing in the full nutritive solution and their 
inflorescence was less highly developed, otherwise the only symptoms of 
Table XXIX. Effect of delayed additions of potassium on the weight of 
Japanese buckwheat plants grown in water cultzire . 
A T utritive solution 
No. of 
Total weight of plants. 
Dry weight of 
Ratio of 
used. 
plants. 
■ 
Green. 
Dry. 
Tops. 
Roots. 
tops to 
roots. 
Grm. 
Grm. 
Grm. 
Grm. 
Solution F. Potassium 
4 
8.052 
0-8692 
0-8181 
0-0511 
present from the be- 
4 
9.186 
0.9250 
0-8698 
0.0552 
ginning. 
4 
10.665 
1.0609 
0.9941 
0-0668 
4 
11-067 
1-1388 
1*0839 
0.0549 
Mean 
1 
2.436 
0-2496 
0-235^ 
0-0142 
1 6.5 
Solution F, less potas- 
4 
10.213 
0.9306 
0.8771 
0-0535 
sium. Potassium 
4 
7-696 
0.8188 
07667 
0.0521 
added after 3 days. 
4 
9.285 
0.9255 
0-8637 
0-0618 
4 
10-231 
0.9798 
0.9199 
0.0599 
Mean 
1 
2-339 
0.2284 
02142 
0-0142 
15-1 
Solution F, less potas- 
4 
5-653 
0.5179 
0.4781 
0.0398 
sium. Potassium 
4 
5-475 
0.4451 
0-4053 
0.0398 
added after 6 days. 
4 
6-oo6 
0.5686 
0.5252 
0.0434 
4 
3-857 
0-3960 
0.3658 
0-0302 
Mean 
1 
1-312 
0.1205 
0-1109 
0-0096 
n -5 
Solution F. less potas- 
4 
2.560 
0-2555 
0-2350 
0-0205 
sium. Potassium 
4 
3-787 
0.3446 
0.3177 
0-0269 
added after 9 days. 
4 
3-085 
0-3219 
0-2991 
0-0228 
4 
2.270 
0-2331 
0.2054 
0-0277 
Mean 
1 
0-731 
0.0722 
0-0661 
0-0061 
10.8 
Solution F, less potas- 
4 
1 - 77 1 
0.3736 
0-1617 
0-0119 
sium. Potassium 
4 
J -455 
0-1461 
o-i 335 
0-0126 
added after 12 days. 
4 
1.784 
0.1769 
0-1665 
0-0104 
4 
2-545 
0-241 1 
02146 
0-0265 
Mean 
1 
0.472 
0-0461 
0-0423 
0-0038 
1 1. 1 
Solution F, Potas- 
4 
0.986 
0. 1 300 
0 -H 75 
0-0125 
sium absent. 
4 
0.834 
0.1281 
0-1193 
0.0088 
4 
0-682 
0-0869 
0-0824 
0-0045 
4 
0-678 
0-1038 
0.0950 
0-0088 
Mean 
1 
0.199 
0-0281 
0.0259 
0.0020 
12.9 
