Inhibition of Abscission of Bean Petiole Explants by Lepidimoide

The effect of lepidimoide on the process leading to abscission was studied in bean (Phaseolus vulgaris L. cv. Masterpiece) petiole explants. The assays, involving observations on the junction of the petiole of primary leaves and the pulvinus, were conducted in the light. Lepidimoide, at concentrations of 1 μm or higher, delayed the abscission process; however, the progression of abscission proceeded at normal rates, and complete abscission resulted. On the other hand indoleacetic acid inhibited the normal senescence resulting in greatly decreased abscission during the observation period. These observations show that lepidimoide only delays abscission, and the kinetics seem to indicate that lepidimoide and indoleacetic acid affect abscission through different mechanisms. Received March 1, 1996; accepted November 4, 1996