Effect of Peroxydisulfate on Vigna radiata Abscission

K₂S₂O₈, applied to the basal end of cuttings of Vigna radiatastimulated leaf abscission in the light or dark. Because inhibitionof leaf sbscission in the dark by IAA was completely abolishedby K₂S₂O₈, and IAA decreased stimulation of abscission by K₂S₂O₈,destruction of IAA in the cuttings by K₂S₂O₈ is indicated. K₂S₂O₈had no effect on leaf abscission when applied as a foliar sprayor when roots of undisturbed seedlings were treated. When appliedproximally or distally to leafless explants, K₂S₂O₈ inhibitedpetiole abscission, and neither IAA nor ethylene had an effecton the inhibition. Although K₂S₂O₈ destroyed IAA in vitro, ithad no effect on abscission inhibitors in macerates of Vignaleaves and corn roots, nor did it destroy the biological activityof IAA added to such macerates. Substances liberated by macerationmay interfere with the ability of K₂S₂O₈ to destroy IAA. (Received May 2, 1981; Accepted August 24, 1981)