Mini-cuttings technique: a new ex vitro method for clonal propagation of sweetgum

Abstract

An efficient production system, which can quickly produce high quality plants, is shown in this study of Liquidambar styraciflua. The mini-cuttings technique was used for ex vitro clonal propagation of three sweetgum clones. The semi-hydroponics system for production of propagules was also tested, and the concentration of indole-3-butyric acid (IBA) for rooting was evaluated. Three adult clones, produced according to conventional cutting processes, were used as mini-stumps and maintained in semi-hydroponics systems of medium size sand. Ten collections of sprouts were prepared to evaluate the production of semi-hydroponics systems (mini-clonal hedges). Sprouts from collection number six were used at different concentrations of IBA solution (0; 500; 1,000; 3,000 and 6,000 mg l−1) to test the mini-cuttings technique. The high survival rates of mini-stumps after ten collections (96.3%), and high annual production per square meter (~2,953 mini-cuttings) showed that the mini-clonal hedges are viable to conduct sweetgum mini-stumps. The formation of 62.5% of healthy plants after hardening under outdoor conditions showed that sweetgum could be successfully propagated by the mini-cuttings technique.