Figure 6: Effect of PA degradation products on root abscission in A. pinnata. The uppermost panel is the schematic representation of higher PAs oxidation by the enzyme polyamine oxidase (PAO) to yield 1,3-diaminopropane (Dap), β-alanine (Ala), and hydrogen peroxide (H2O2). Experiments in the presence of (a) 2 mM Dap () or 2 mM Ala () and (b) 2, 4, 6 and 10 mM H2O2 (). Standard error bars are only shown where larger than the symbols used. The experimental conditions were similar to those in Figure 2.