The Physiology of Growth in Apple Fruits V. Soluble Nitrogen Constituents

Abstract

The ninhydrin-reacting compounds of the apple fruit were studied during development on the tree. The compounds present show little variation, but glutamine, conspicuous in very young and in over-mature apples, disappears at intermediate stages. The increase in soluble nitrogenous compounds occurring in over-mature apples left on the tree (Pearson and Robertson 1953) is confirmed qualitatively. An account is given of the chromatographic behavior of several unidentified ninhydrin-reacting substances found in extracts of apple fruits, leaves and stems.