Studies on the Nitrogen Metabolism of the Barley Plant (Hordeum Sativum)

Abstract

In detached harley leaves held at constant temperature in the dark, thereis an increase in "soluble" and a corresponding decrease in "solid" nitrogen. Inmature leaves, glutamine accumulates in the early stages of starvation and laterdecreases concurrently with an increase in asparagine. In detached seedlingleaves, the glutamine content remains low throughout, the sequence of eventsotherwise resembling that found with mature leaves. Changes in the nitrogenousfractions during autolysis, in sterile conditions, of barley leaf tissuediffer greatly from those found with intact detached leaves. "Soluble" nitrogenincreases, but neither amide nor ammonia accumulates.

Soil Fertility and the Organic Composition of Plants, Lysine, Arginine and Aspartic Acid Variations1

“…Microbiological methods of analysis for amino acids have been shown to give acceptable quantitative results (7,12,18,20,22). All amino acids were determined on whole plant tissue which had been hydrolyzed with 10% hydrochloric acid or 4N sodium hydroxide.…”

“…McKee (12) found that asparagine accumulated in large amounts in "dying" barley leaves and seedlings with a simultaneous decrease in other nitrogen fractions. This suggested an increased rate of proteolysis or a decreased rate of biosynthesis, However, work by Iljin (9) showed that lime-ind~ced chl~rosis caused a d~crease in protein nitrogen and an mcrease m nonprotem mtrogen.…”