STUDIES OF THE METABOLIC RELATIONS OF ALLANTOIN IN WHEAT

Changes in the allantoin and allantoic acid content of germinating seedlings and aging leaves of wheat were followed. The results of experiments on photosynthetic assimilation of C 14 O 2 and the feeding of glycine-C 14 and glyoxylate-C 14 indicate that in wheat seedlings the root is probably an important site of allantoin synthesis. Glycine-C 14 was found to be a better precursor of allantoin-C 14 than glyoxylate-C 14 . Allantoin-C 14 was not synthesized from urea-C 14 . A scheme for allantoin synthesis which is based on these results is outlined.