Soybean plants (Glycine max'Harasoy') were cultured in a controlled environment room and studied at seven ages ranging from 16 to 40 days after flowering. Fruits from each age group were labeled by translocation of organic compounds from leaves which had photosynthetically incorporated14CO2. Leaf blades, petioles, and seeds were extracted in boiling ethanol at the termination of labeling experiments. Seeds were also harvested and extracted 1, 2, and 8 days after labeling. Distribution of label in leaf blades and petioles was essentially the same in all age groups with more than 90 of the activity in petioles being found in carbohydrates. Little or no translocation of amino acids and organic acids was occurring. In seeds, most of the label appeared in the carbohydrate fraction immediately after labeling; however, at 2 and 8 days after labeling the label seemed to be transferred to lipids and the ethanol-insoluble residue. The rate of transfer decreased as a function of seed age. Levels of activity in the amino acid and organic acid fractions were low in all samples.
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