The objectives of this study were to determine if the partitioning of recently fixed carbon between starch and water-soluble compounds could be altered by increasing the pod load in the leaf axil, and if the presence of source leaves acropetal to such a node would influence the partitioning of carbon within the subtending leaf. Soybeans (Glycine max L. Merr. cv Hodgson 78) were grown to full-bloom in a controlled environment chamber, and then deflowered at all nodes except the eighth. This treatment resulted in an 83% increase in the number of pods at the eighth node. At 24 days after flowering, one-half of the treated plants were girdled above the untreated node. Forty-two hours later, the eighth trifoliolate was pulsed with 14CO2 and sampled for radiolabeled starch and water-soluble compounds (WSC) at 0.5, 2, 4, 8, 12, and 24th after labeling.When no girdling was applied above the increased pod load at the eighth node more label was accumulated by the pod walls (+6.9%) and seeds (+6.3%) when compared to the controls. Starch accumulation was not altered in the labeled leaf of the nongirdled plants. When the stem was girdled above the eighth node, significantly less starch was retained in the labeled leaf. Girdling also resulted in an increase in label accumulation by the pod walls (+5.4%) and seeds (+6.6%). These data suggest that the plant will change the distribution patterns of assimilate to supply added sink demand before altering the partitioning of recently fixed carbon in the subtending leaf.
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机译：这项研究的目的是确定是否可以通过增加叶腋中的豆荚负荷来改变淀粉和水溶性化合物之间最近固定的碳的分配，以及是否存在源于这种结节的子叶丙烯醛会影响其分布。碳在对向的叶子内分配。大豆（Glycine max L. Merr。cv Hodgson 78）在受控环境室内生长至全花，然后在除第八个以外的所有节点上脱花。这种处理导致第八个节点处的豆荚数量增加了83％。开花后第24天，一半的处理过的植物环绕在未处理的节点上方。 42小时后，用 14 CO2脉冲第八小叶草酸酯，并在标记后第0.5、2、4、8、12和24天对放射性标记的淀粉和水溶性化合物（WSC）进行采样。与对照相比，当在第八个节点上增加的豆荚负荷不施加环带时，豆荚壁（+ 6.9％）和种子（+ 6.3％）会累积更多的标签。在未环带植物的标记叶中，淀粉积累没有改变。当茎环束在第八节以上时，标记的叶中保留的淀粉明显减少。环剥还导致豆荚壁（+ 5.4％）和种子（+ 6.6％）的标签积累增加。这些数据表明，该植物将改变同化物的分布模式，以提供增加的汇需求，然后再改变对向叶片中最近固定的碳的分配。
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