MICROPROPAGATION OF ZANTEDESCHIA AETHIOPICA (L.) SPRENG.: TOWARDS ITS COMMERCIAL USE IN THE CUT FLOWER INDUSTRY

摘要

Commercial application of micropropagation techniques has predominantly been limited by factors such as high production costs as a result of undesirable growth rates in vitro and high labour costs. The present study aimed to establish a rapid, efficient and cost-effective micropropagation protocol for Z. aethiopica. Both rhizome and leaf explants were evaluated for in vitro propagation. Despite its toxicity, the most effective decontamination sterilant was mercuric chloride (HgCl2). The decontamination frequency recorded in the rhizome explants was generally low (28%), using 0.2% (w/v) HgCl2. Leaf explants exhibited a higher decontamination frequency (78.3%) when using 0.1% (w/v) HgCl2 for 30 min. After four weeks, regenerated axillary shoots from rhizome explants were cultured on Murashige and Skoog (MS) multiplication media. The media contained a combination of different concentrations of N-6-benzyladenine (BA) and a single concentration of indole-3-butyric acid (IBA). MS medium supplemented with 4 mg 1.1 BA and 1 mg l(-1) IBA produced the highest mean number of axillary shoots (2.8 +/- 0.5), and significantly higher shoot length (5.9 +/- 0.8 cm) and fresh weight (0.7 +/- 0.1 g) after four weeks. A 94% survival rate was recorded when in vitro-derived shoots were rooted and acclimatized ex vitro on a soil mixture containing 1 : 1 (v/v) vermiculite : sand. Rooting occurred spontaneously during acclimatization.