Rooting characteristics of stem tip cuttings in Ardisia pusilla as influenced by cutting stage, rooting medium, temperature, and plant growth regulator pretreatment.

To produce commercially acceptable pot plants of Ardisia pusilla, vegetative propagation method such as stem tip cutting has been used in general. Thus, the production of uniform and vigorous rooted cuttings is required. This study was conducted to screen an adequate stem tip cutting stage for rooting, to select an adequate rooting medium, to find its favoring temperature for rooting, and to develop a suitable method for promoting root development. The stages of stem tip cuttings could be divided into five groups by the degree of leaf expansion and chlorophyll contents. Stem tip cutting with green leaves was found to be the best rooting potential among the five types of stem tip cuttings. In rooting medium, roots dry weight showed 152% increase in only vermiculite compared to in a commercial growing medium (perlite:peatmoss=1:1, v/v). Rooted cuttings of A. pusilla showed very sensitive rooting potential according to temperature and optimal rooting temperature was found to be 20-25℃. Although indole-3-butyric acid (IBA) used for rooting increased the number of roots in a concentration-dependent manner regardless of the pretreating methods, dipping treatment into a 1500 ㎎ㆍl?¹ IBA solution for 10 min was the most effective on increasing the number of roots. However, cuttings treated with 0.4% naphthylacetamide (NAA) talc showed the heaviest root dry weight than those with the other treatments. Thus, NAA talc was the most acceptable rooting promotion method for producing rooted cuttings due to simple and practical method used by farmers. In conclusion, rooting characteristics of cuttings in A. pusilla was very dependent on cutting stage, rooting medium, and rooting temperature.