Nitrogenous compounds and nitrogen metabolism in the Liliaceae. 6. Changes in nitrogenous composition during the growth of Convallaria and Polygonatum.

Azetidine-2-carboxylic acid has been recognized as an important constituent of the 70% ethanolsoluble-nitrogen fraction of many liliaceous plants (Fowden, 1956; Fowden & Steward, 1957). ConvaUaria majali8 (lily of the valley) and Polygonatum multiflorum (a Solomon's seal) are two common representatives of these plants im Britain, and part 6 of this series (Fowden & Bryant, 1959) described experiments in which various 14Clabelled substances were supplied to tissues of these two plants to obtain information about the manner of biogenesis of azetidine-2-carboxylic acid. In this paper variations in the major nitrogenous fractions present in different organs of the plants during growth have been investigated to ascertain in another way where azetidine-2-carboxylic acid is synthesized and at what stage of the plant's development synthesis occurred. The importance of the imino acid in the general nitrogen economy of the plants is discussed.