THE INFLUENCE OF PHYTIN ON THE GROWTH 



OF LUPIN SEEDLINGS 



A. R. ROSE 



(Laboratory of Biological Cliemistry of Columbia University, at the College of 

 Physicians and Surgeons, New York) 



I. INTRODUCTION 



Inosite, a cyclic Compound, is a very important constituent of 

 all seeds, where it is chemically combined as phytin with 

 phosphate of the alkaline earths. Because this Compound (phytin) 

 is stored in seeds and contains more than half of the phosphorus 

 that is availa'ble at the beginning of plant growth, we may justly 

 assume that its function in the physiology of plants is highly sig- 

 nificant ; though as to just what röle in phyto-mechanism, phytin may 

 play, we have as yet no knowledge. The presence in the seed of a 

 phytase would suggest the correctness of Postenak's inference that 

 phytin is a reserve material designed to supply phosphorus for the 

 process of germination and subsequent growth. 



It is now a matter of common knowledge that growing plants 

 require phosphate. In agricultural practice, phosphate is supplied 

 to the soil incidentally, by plowing under many kinds of organic 

 refuse; or intentionally, by adding inorganic phosphates from min- 

 eral beds, or the organic fertilizer, guano. Nagaoka^ investigated 

 the relative values of organic phosphates from animal and from 

 plant sources, and found that the animal products gave better 

 results than the vegetable. His associates, Aso and Yoshida,^ later 

 studied the comparative fertilizing values of different vegetable 

 substances containing phosphorus, and demonstrated that phos- 

 phoric acid of inosite-hexaphosphate (phytin) is more available for 

 plants than protein-phosphate (nucleoprotein), but less available 

 than fat-phosphate (lecithan). The results of their experiments 



* Nagaoka : Bull. Coli. Agr., Tokyo, vi, no. 3. 



* Aso and Yoshida : Jour. Coli. Agr., Tokyo, i, 1909, pp. 153-161. 



428 



