Department of Agronomy, University of Kentucky, Lexington, Kentucky 40506.
Plant Physiol. 1978 Nov;62(5):812-4. doi: 10.1104/pp.62.5.812.
Radioactive photosynthetic assimilates, translocated to a soybean (Glycine max [L.] Merr. ;Fiskeby V') pod can be measured directly by excising the stylar tip of the pod under 20 mm ethylenediaminetetraacetate solution (pH 7.0) and allowing the material to leak into the solution. Pods at the source node received approximately 50% of the (14)C exported from the source leaf to the pod and leaked approximately 1 to 3% of this into the solution. More than 90% of the (14)C that leaked from the pods was found in the neutral fraction and, of this, about 93% was in sucrose. Fifteen amino acids were identified in the leakage including: alanine, arginine, asparagine, gamma-aminobutyric acid, glutamine, glycine, histidine, isoleucine, leucine, lysine, phenylalanine, serine, threonine, tyrosine, and valine. The majority of the (14)C in the basic fraction was found in serine ( approximately 30%) and asparagine ( approximately 23%). The inorganic ions K, Ca, P, Mg, Zn, and Fe were found in the leakage component. Nitrate was not detectable in the collected leakage solution. The absence of NO(3) (-) and the large proportion of the label in sucrose suggest a possible phloem origin for most of the material. The technique provides an uncomplicated, reproducible means of analyzing the material translocated into and through the soybean pod, as well as following the time course of label arrival at the pod.
放射性光合作用产物可被直接测量，方法是在 20mm 乙二胺四乙酸（pH7.0）溶液下切除豆荚的花柱尖端，并让材料渗漏到溶液中。在源节点的豆荚接收了约 50%从源叶输出到豆荚的 (14)C，并将约 1%至 3%渗漏到溶液中。从豆荚中泄漏的 (14)C 超过 90%存在于中性部分，其中约 93%在蔗糖中。在渗漏物中鉴定出了 15 种氨基酸，包括：丙氨酸、精氨酸、天冬酰胺、γ-氨基丁酸、谷氨酰胺、甘氨酸、组氨酸、异亮氨酸、亮氨酸、赖氨酸、苯丙氨酸、丝氨酸、苏氨酸、酪氨酸和缬氨酸。碱性部分中 (14)C 的大部分存在于丝氨酸（约 30%）和天冬酰胺（约 23%）中。在渗漏成分中发现了 K、Ca、P、Mg、Zn 和 Fe 等无机离子。在收集的渗漏溶液中未检测到硝酸盐。NO(3) (-)的不存在和标签在蔗糖中的大比例表明，大部分材料可能来自韧皮部。该技术为分析进入和穿过大豆荚的转移物质以及追踪标签到达豆荚的时间过程提供了一种简单、可重复的方法。
