TRANSLOCATION OF PLANT FOOD AND ELABORATION OF 

 INORGANIC PLANT MATERIAL IN WHEAT SEEDLINGS. 



HiTTRODUCTIOF. 



The results on the leaching of inorganic plant constituents from 

 plants, especially at the ripening stage, which were published by 

 the authors in the 1908 Yearbook of the department, as well as 

 their unpublished work on the chemical study of field crops, par- 

 ticularly cereals, throughout the whole growing period, have shown 

 the desirability of studying the chemical and physiological changes 

 which take place during the very early stages of plant growth; 

 that is, during the first two weeks after germination. 



Investigations on the growth of seedlings have, for the most part, 

 been confined to the respiration, the decomposition of the protein 

 of the plant during germination, and the detection and isolation of 

 various compounds formed in the plants as a direct result of the 

 vital processes. Comparatively little work has been undertaken 

 along the lines of the investigation herein reported, namely, the 

 translocation of the inorganic salts from the seed to the aerial por- 

 tion of the plant and to the rootlet, their accumulation in the plu- 

 mule, and the formation of the various organic constituents of the 

 plant. 



In 1874 Kellner ^ made a study of pea seedlings, and was the first 

 to show that the respiration was greater in dilute nitrate solution 

 than in water culture. His analyses of the original and of the 

 steeped pea showed that on steeping an appreciable amount of 

 each of the inorganic constituents was dissolved, and that the amount 

 of soluble organic substances increased, wiiile the actual and total 

 amount of inorganic salts decreased. Iwanow ^ and Zaleski found that 

 in seedlings grown in the dark the relative amount of inorganic phos- 

 phorus increased at th6 expense of the organic phosphorus. On 

 the other hand. Hart and Andrews ^ showed the reverse to be true; 

 in other words, that the inorganic phosphorus did not increase, but 

 that there was an increase in soluble organic phosphorus. 



During the germination of sunflower and hemp seed in the dark 

 Frankfurt ^ found that there was an increased formation of lecithins, 



1 Landw. Versuchs-Stat., 1874, 17: 408. 3 Amer. Chem. J., 1903, 30 : 483. 



2 J. exper. Landw. (Russian), 1902, 3 (1): 53. « Landw. Versuchs-Stat., 1894, 43 : 143. 



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