
BRIECLR ARTICLES: 
NITRATES AS A SOURCE OF NITROGEN FOR SAPRO- 
PHYTIC FUNGI 
The readiness with which different classes of plants make use of 
nitrogenous inorganic material has been variously demonstrated. It 
is well understood that salts of nitric acid, and to a less extent ammo- 
nia, serve as nutrient material for the higher plants, and that free nitro- 
gen and salts of nitrous acid are worked upon by certain bacteria in 
such a way as to make them available as a nitrogen food supply. But 
Pfeffer* states that phanerogams and saprophytic fungi are unable to 
assimilate nitrites. 
With a view of testing this latter point certain fungi were grown in 
culture solutions containing ammonium chlorid, potassium nitrate, 
potassium nitrite, hexamethylenetetramine, and peptone. The cul- 
ture was prepared with 200% chemically pure water obtained by redis- 
tilling from a solution of potassium permanganate until free from 
every trace of ammonia, 10% cane sugar, 0.5 magnesium sulphate, 
o.1™ acid potassium phosphate, and a trace of ferric chlorid. To 10 
of the sterilized solution was added 0.1 of one of the nitrogen con- 
taining substances. One drop of this preparation placed on a cover 
glass was inoculated with the fungus and the cover glass inverted 
over the cell and placed in the thermostat for cultivation at 28° C. 
The fungi used for inoculation were Aspergillus flavus and Botrytis 
vulgaris. Throughout the experiment care was taken to have the 
solutions and apparatus thoroughly sterilized, and all of the salts used 
were chemically pure. 
Duplicates of each were prepared, also checks using the solution 
without the nitrogen containing compound. The cultures were exam- 
ined at intervals for from one to three days. At the expiration of the 
time unquestionable results were obtained. In potassium nitrate and 
potassium nitrite thé fungi grew with apparently equal vigor, Aspet- 
gillus developing well formed fruit bodies. Hexamethylenetetramine 
showed itself an excellent source of food, since both fungi grew an 
* Physiology of Plants, translated by Ewart, 406. 1899. 
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