Physiology of Pea Fruits IV. Changes in Sugars in the Developing Seed

Paper chromatographic methods were developed for the estimation of sugars in plant tissues and were used to follow changes in some individual sugars during the development of the pea seed. Sucrose was the predominant sugar present in the seeds and there were smaller quantities of fructose, glucose, and galactose. The amounts of fructose and glucose were approximately equal at all stages of develop. ment. The sucrose, fructose, and glucose contents of the seed increased in the early stages of development but decreased during the phase of rapid starch synthesis. The galactose content increased to a maximum at a later state than the other sugars estimated. The concentrations of sucrose, fructose, and glucose in the seeds were compared with the concentrations in the leaves, stems, and hulls. The possible significance of the changes in sugars in relation to the metabolism of the pea seed is discussed.