Regulation of Bud Rest in Tubers of Potato, Solanum tuberosum L

Abstract
Using the electron microscope, we compared the effects of abscisic acid and gibberellin A3 on excised buds from resting potato (Solanum tuberosum L.) tubers. Cells of abscisic acid-treated buds became progressively more vacuolated during a 12-hour time course study as compared with control (water) and gibberellin A3-treated buds. Concentric configurations of endoplasmic reticulum were present in apical cells of freshly excised buds. After about 6 hours these configurations began to open and disperse, and after 12 hours, intact concentric configurations were no longer evident. Both abscisic acid and gibberellin A3 induced opening and dispersal of the concentric configurations, sometimes as early as 0.5 hour after excision and treatment with hormones.