Biological and Medical Sciences Division, U.S. Naval Radiological Defense Laboratory, San Francisco, California.
Plant Physiol. 1966 Sep;41(7):1145-51. doi: 10.1104/pp.41.7.1145.
A perfusion bridge technique is described which permits the continuous collection of exudations from both ends of corn root segments. By exposing the central portion of the segments to radiocalcium, the amounts and rates of tracer movement in either direction may be determined. Typically, a peak in both acropetal and basipetal transport occurs at about 90 minutes after exposure to tracer. This transport peak is followed by a sharp decline to relatively low transport rates. Thereafter the 2 perfusates from opposite ends of a segment pair show significant differences. The acropetal increments decrease somewhat erratically to 0 at 10 to 12 hours, while the basipetal increments steadily increase to a steady-state value which remains constant from 8 to 24 hours. After a segment pair has reached steady-state polar transport, a fresh cut on the apical ends causes the resumption of acropetal transport. Such response suggests that polar transport in these root segments is at least partially a wound response. A possible explanation of the complex transport behavior is advanced.
描述了一种灌流桥技术，该技术允许从玉米根段的两端连续收集渗出物。通过将段的中心部分暴露于放射性钙，可以确定示踪剂在任一方向上的移动量和速度。通常，在暴露于示踪剂后约 90 分钟，在向顶和向基运输中都会出现一个峰值。此运输峰值之后，运输速度急剧下降至相对较低的水平。此后，来自一对段的相反端的两种灌流液显示出明显的差异。向顶增量有些不稳定地逐渐减少到 10 到 12 小时的 0，而向基增量则稳定增加到 8 到 24 小时保持不变的稳定状态值。在一对段达到稳定的极性运输后，在顶端末端进行新的切割会导致向顶运输的恢复。这种反应表明，这些根段中的极性运输至少部分是一种创伤反应。提出了对这种复杂运输行为的可能解释。
