On the Poisonous Action of Ammonium 

 Salts upon Plants. 



BY 



S. Takabayashi. 



It has been observed that many plants show better develop- 

 ment with nitrates as a source of nitrogen than with ammonium 

 salts, further that the yield of a crop decreased in certain in- 

 stances, when the ammonium salts were used in too high a con- 

 centration. Moreover, it is a fact that ammonium salts are never 

 found stored up in plants, while nitrates can be stored to a con- 

 siderable extent. Plants manured with ammonium salts contain 

 only very small quantities of ammonia'" while most of the am- 

 monia absorbed in excess is converted into asparaginc, as 3^r. 

 Khioshita and M}-. Suzuki of this College have proved. 



A noxious effect of ammonium salts upon the green plants 

 when administered in excess, would probably induce the 

 plants to transform the ammonia quickly into asparagine, which 

 is a perfectly indifferent substance for them.'^' 



The poisonous action of ammonium salts must naturally be 

 much more rapid and more clearly exhibited on plants, whose 

 store of carbohydrates is insufficient to transform all the absorbed 

 ammonia within a certain time into asparagine. 



A series of preliminary experiments showed that ammonium 

 carbonate in a concentration of 0.5^ easily kills various veget- 



(1) E. Schulzeioxml with lupin shoots that the nitrogen present in the form of ammonia 

 amounted only to 0.085% of the dry, or 0.0046% of the fresh substance. U. StizuM, of 

 this College found in 100 parts of fresli buck-wheat plants, kept for 9 days in 0.1% am- 

 monium chloride solution, only 0.08 parts of ammonia. (This Bulletin II. No 7.) 



(2) Ammonium salts also exert a poisonous action upon animals, that is, if more is 

 administered than can be transformed within a certain time into urea, which, as A'cncH 

 has shown, is prepared in the liver by way of carbamate of ammonia. As soon as the 

 liver is prevented from accomplishing this, ammonia will increase in the blood and lead 

 to poisonous phenomena. {-W-nrki, Pawioiv and Zalt-ski,') 



