Department of Botany, University of California, Davis, California 95616.
Plant Physiol. 1968 Sep;43(9):1380-8. doi: 10.1104/pp.43.9.1380.
(14)C-assimilates were accumulated by the veins in the blades and transported basipetally into the petioles of detached leaves of Red Kidney bean (Phaseolus vulgaris L.). Neither process was greatly affected by mild moisture stress, age of fully enlarged leaves, or period in the dark prior to exposure to (14)CO(2). However, both vein loading and transport into petioles were greatly reduced by oxygen deficiency. The basipetal transport of (32)PO(4) also did not appear to be greatly reduced by 6 or 8 days of darkness prior to the application of phosphate-(32)P, followed by a transport period of 1 day in the dark. Endothall at 5 x 10(-3)m was effective in stopping basipetal flow of (32)P. It is considered that transport in leaves may be powered by forces in the plasmodesmata of the cell walls between the border parenchyma and phloem.
（14）C 同化产物在叶片的维管束中积累，并被逆着浓度梯度运输到脱落的菜豆（Phaseolus vulgaris L.）叶柄中。轻度水分胁迫、叶片充分展开后的年龄或暴露于（14）CO2 之前的黑暗期都不会对这两个过程产生很大影响。然而，缺氧会大大减少叶脉的装载和向叶柄的运输。在应用磷酸盐-（32）P 之前先进行 6 或 8 天的黑暗处理，然后在黑暗中进行 1 天的运输期，（32）PO4 的向基运输似乎也不会大大减少。5 x 10（-3）m 的端噻吩有效地阻止了（32）P 的向基流动。可以认为，叶片中的运输可能是由细胞壁中的胞间连丝中的力驱动的，胞间连丝位于边缘薄壁组织和韧皮部之间。
