A simple system for determining the phloem mobility of compounds using excised pods of lupin (Lupinus albus L.)

Lupin pods were isolated from the plant and the pedicels placed in solutions of either radiolabeled sucrose, glucose, abscisic acid, or gibberellin A₉ (GA₉). Phloem exudate was collected from the cut stylar ends of the pods and both quantitative and qualitative data were obtained on the activity in the sap. Fed sucrose, abscisic acid, and GA₉ were found in phloem exudate, but labeled glucose was immobile as the monosaccharide and activity in exudate appeared in sucrose.Abbreviations GA gibberellic acid - ABA abscisic acid - TLC thin layer chromatography