Evolution of Nitrogen Compounds From Soybean (Acetaldehyde Oxime, Nitrous Oxide, N-15)
Soybean seedlings {Glycine max (L.) Merr. cv. Williams, 24 days after planting, grown on nutrient solution containing 15 mM NO(,3)('-)} evolved substantial amounts of N compounds in an open gas exchange system. Air exiting the shoot compartment was passed through a chemical trapping system. Traps I, II, and III contained 0.1 N H(,2)SO(,4), 1 N KOH, and 1 N KOH:0.1 M KMnO(,4), respectively. The N content of the trapping solutions was determined by steam distillation methods. Over a 24 h period, the shoots evolved 840 (mu)g N(.)plant('-1)(.)d('-1). Maximum evolution rates occurred near the end of the light period. Trap II retained 62.1% of the N evolved, whereas traps I and III retained 18.7% and 19.2%, respectively, suggesting that the bulk of the N compounds evolved were acidic. Ammonia plus amines (trap I) comprised less than 105 of the N evolved. Substantial amounts of oxidized inorganic N were detected in the traps, indicating that part of the N evolved was more oxidized than NH(,3). Evolution of N compounds detected as NO(,x) was also observed (mean rate for 24 h was 0.57 (mu)g N(.)plant('-1)(.)h('-1)). The results of hydrolysis experiments (acidic and alkaline conditions) indicate that part of the N evolved was organic.
University of Illinois - Urbana-Champaign
Networked Digital Library of Theses and Dissertations
University of Illinois at Urbana-Champaign