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SUZUKI ; 



1. Ammonium salts, (and also urea). 



2. Nitrates. 



(2) . Asparagine is formed not only by keeping full-grown 

 plants in the dark, but also can be formed in full daylight under 

 certain conditions. 



(3) . Synthetic formation of asparagine is only possible, 

 when sugar is present in the plant, and at the same time some 

 condition for protein formation is wanting. Excess of sugar 

 prevents the asparagine formation from proteids, but it does 

 not prevent the synthetical formation of asparagine ; it even sti- 

 mulates its formation. 



(4) . Ammonia is never stored upas such in plants ; it disap- 

 pears quickly forming innocuous compounds ; but when the ne- 

 cessary amount of sugar is wanting, the ammonia can not be con- 

 verted and remains as such (experiments with buckwheat) to a 

 small extent in the plant ; a larger amount is noxious. 0 ' 



(5) . Ammonium salts arc generally better than sodium 

 nitrate for asparagine production. 



(6) . Among the several ammonium salts, ammonium chlo- 

 ride is the best, while the ammonium phosphate is always less 

 favourable for the formation of asparagine ; very probably the 

 formation of nuclein and new cells are stimulated very much by 

 phosphates ; the asparagine once formed is thus easily trans- 

 formed into proteids. 



Urea is generally better than ammonium salts for asparagine 

 production (except with barley experiments). 



(7) . For the conversion of nitrates, a high temperature and 

 the presence of sugar are necessary, otherwise they remain as 

 such stored up in the plants for some time. 



(8) . The conversion of asparagine into proteids is only pos- 

 sible when all conditions are fulfilled. One of the most es- 

 sential conditions is of course the presence of sulphates. 



(9) . In etiolated shoots sodium nitrate can not be con- 

 verted into asparagine but urea is capable of yielding it. 



(10). In etiolated shoots the application of sugar increases 

 the amount of asparagine, when sodium nitrate or ammonium 

 salts are offered. 



(1) Mr. Aoyama in our laboratory made some experiments which show very clearly 

 the poisonous action of ammonium salts, when the necessary amount of sugar is not pre- 

 sent to transform them into asparagine. 



