28 TKANSLOCATIOK OF PLANT FOOD IN WHEAT SEEDLINGS. 



REDUCING SUGAR AND SUCROSE. 



Tables 14 and 15 show how great have been the changes in both 

 the reducing sugars and the hydrolyzable sugar during the 15 days of 

 the hfe of the seedhng. 



Table 14. — Reducing sugars (as de.vtrose) in residual seeds and axes when grown for 15 

 days in solutions containing one nutrient. 



Parts of plant and age. 



Control 

 solution. 



Nitrate 

 solution. 



Phos- 

 Potash I phoric 

 solution. I acid solu- 

 tion. 



Original seed. 



Seeds: 



3 days... 



5 days... 



7 days... 



9 days. . . 

 12 days... 

 15 days. . . 

 Axes: 



3 days. . . 



5 days. . . 



7 days... 



9 days-. . . 



12 days... 



15 days... 



Total plants: 



3 daj's... 



5 days... 



7 daj-s... 



9 days... 

 12 days... 

 15 days... 



Mg. 



192.4 



193.8 



Lost. 



81.0 



22.6 



148.0 

 253.7 

 '267.9 

 262.3 

 180.1 

 91.3 



246.6 

 446.1 

 461.7 



261.1 

 113.9 



J/?. 



117.0 



173.3 



115.6 



72.0 



24.5 



8.3 



136.8 

 267.9 

 265.7 

 324.8 

 157.0 

 105.0 



253.8 

 441.2 

 381.3 

 396.8 

 181.5 

 113.3 



Mg. 



122. 9 

 160.5 

 134.4 

 91.0 

 46.7 

 21.7 



124.8 

 208.8 

 228.3 I 

 244.7 

 118.2 

 79.2 



247.7 

 369.3 

 362.7 

 335.7 

 164.9 

 100.9 



Mg. 



112.5 

 157.0 

 104.4 

 80.5 

 40.3 

 12.8 



130.3 

 257.4 

 246.4 

 298.8 

 167.4 

 121.0 



242.8 

 414.4 

 350.8 

 379.3 

 207.7 

 133.8 



In the original seed there was no reducing sugar; 100 seeds con- 

 tained, however, 0.095 gram of hydrolyzable sugar. During the 

 process of growth the formation of reducing sugar in the seed is rap- 

 idly increased up to the fifth and sixth days. (See Table 14.) This is 

 not only coincident mth the breaking down of the hydrolyzable sugar, 

 but is a result of the hydrolysis of the starch as well, inasmuch as a 

 much larger amount of reducing sugars is found than could be ac- 

 counted for by the original hydrolyzable sugar in the seed. After the 

 fifth and sixth days there was a rapid faUing off in the amount of 

 reducing sugars found in the seed until at the end of the 15th day 

 the residual seed contamed but a trace of this substance. In the axes, 

 however, the reducing sugars increased up to about the ninth day, 

 when they contained about three times as much of these sugars as the 

 original seed did of hydrolyzable sugar. 



After tliis period there is a gradual decrease in reducing sugars, even 

 in the axes, until on the 15th day, the amount present approxi- 

 mated that of the hydrolyzable sugar originally present in the seed, 

 namely, 0.095 gram per 100 plants. 



The amount of reducing sugar found in the residual seed is some- 

 what higher in the control solution than under the influence of nitro- 

 gen, phosphoric acid, or potash. The greatest amount of reducing 

 sugar was found on the ninth day in the axes of plants grown in the 



