Changes in nitrogen metabolism in the wheat root tip following growth and vernalization

Sequential changes in the alcohol-soluble amino acid fraction of vernalized and control root tips of Triticum aestivum var. Marquis (spring) and Rideau (winter) wheats have been followed. Substantial changes in this fraction could be related to developmental changes in the root tip, with protein synthesis occurring most rapidly in the region of elongation. Vernalization superimposed additional, consistent changes mainly in the content of asparagine, glutamine, glycine, and glutamic acid. Incorporation studies using 14 C-glutamic acid and aspartic acid served to emphasize the distinct metabolic differences between the mitotic and elongating regions of the root tips. The activity of glutamic acid – alanine transaminase was also studied.