APPENDIX F. 



THE PHYSIOLOGICAL FUNCTIONS OF THE NITRATES AND PHOSPHATES 



IN THE SUGAR-BEET. 



The following remarks made by Herr Strohmer, at a late meeting of the Austro- 

 Hungarian Association of Sugar Manufacturers, constitute so succinct a resume" of 

 the present knowledge of the position and value of the phosphates and nitrates of the 

 alkalies in their relation to the physiological functions of the sugar-beet, that we 

 consider it of value to transcribe them here in full : 



Among the conditions of the growth of the sugar-beet, nutrition occupies the high- 

 est rank. Numerous tests of manures have been made to resolve this question, but in 

 spite of the trouble and care bestowed, it has been impossible to deduce from them a 

 general rule. From these experiments I may cite those made by Gilbert in later days, 

 showing that by the mineral manures alone or with slight doses of nitrogen constant 

 crops may be obtained, and that the mode of action of nitrogenous manures is rather 

 indirect than direct, and consists in rendering the assimilation of other nutritive ma- 

 terials more ready. In general we may say that tests of manures possess a purely 

 local value ; for one and the same place this may, however, render great service and 

 be of the greatest importance. 



The classical work of Hanaman on the soil of the neighborhood of Lobositz gives 

 proof of this. But the real question can only be determined by cultural experiments, 

 and the true significance of the results deduced by a knowledge of the laws of nutri- 

 tion. These laws can be defined only by experiments executed in a truly scientific 

 manner and with the aid of chemistry in alliance with physiology. Experiments with 

 manures have heretofore been as numerous as the experiments in vegetation, under- 

 taken in later years, have been few. The special literature of the subject could not 

 have said less of this work. 



It is but a few years since Dr. Kohlrausch and myself published a notice upon 

 experiments in nutrition. It followed from them that an augmentation of the con- 

 tent of sugar in the beet does not correspond with an increasing manuring with nitrate 

 of potash, and that with regard to the total sugar produced in the plants no deter- 

 mined relation is attached to increasing doses of nitrate of potash. It is therefore 

 probable that potassium and nitric acid paralyze each other in part in their physio- 

 logical action in the production of sugar in the beet. The experiments also enable us 

 to recognize that in all probability the content of nitric acid in the dry matter of the 

 beet is augmented by increasing doses of nitrates. We would not positively declare 

 at this time that nitrates interfere with the formation of sugar, because beets which 

 we ourselves have procured, though having a normal appearance, showed only 5 to 

 10 per cent, of sugar, while the beets of a preceding experiment made at Prilep by Dr. 

 Kohlrausch, had always given 10 to 16 per cent. It might therefore happen that the 

 lower richness was the consequence of local influences. Hanaman has shown in a 

 brilliant work that the Jess free (moins de'gage'e) situation of a soil has a powerful 

 influence upon the quality of the beet. 



In order to clear up this question we made other experiments in 1876 and 1877 with 

 nitrate of soda and phosphate of potash. Beets manured with the first fertilizer were 

 in both years much less rich in sugar than roots manured with the phosphate. On 

 the other hand they showed a higher content of nitric acid and potien with a quo- 

 tient of purity much lower than the other roots. The principle we expressed as 



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