Enhanced Rooting of Wounded Mung Bean Cuttings by Wounding and Ethephon1

Rooting of light-grown cuttings of mung bean [ Vigna radiata (L.) R. Wilcz.] was stimulated by wounding and by the ethylene-releasing compound (2-chloroethyl)phosphonic acid (ethephon) at 0.1, 1.0, and 10.0 mg/liter with a maximum response at 1 mg/liter. The inhibitor of ethylene synthesis, aminoethoxyvinylglycine (AVG), at 10 µ m , significantly decreased root number in wounded cuttings, but ethephon overcame this inhibition. Rooting in wounded cuttings was stimulated by indolebutyric acid (IBA) at a concentration of 5 × 10 −6 m but root numbers decreased by 56% with AVG + IBA. Application of ethephon or IBA, and extensive wounding, caused an upward redistribution of roots away from the base of the cuttings.