Ammonia?An Early Stable Product of Nitrogen Fixation by Soybean Root Nodules F. J. Bergersen

Abstract

Experiments with detached soybean root nodules exposed to atmospheres containing very high enrichments of 15N 2 for short periods of time have shown that at about 1 min from the commencement of fixation more than 90% of the soluble fixed nitrogen could be accounted for as ammonia. The proportion of the newly fixed nitrogen in this form then rapidly diminished as the ammonia was rapidly converted to amino and other compounds. After fixation for 10 min, only about 20 % of the newly fixed nitrogen was ammonia. Fixed nitrogen in amides rose steadily for 1 hr and after that time was equal in concentration to the fixed nitrogen in the form of ammonia.