Rooting Response of Foliage Plants Affected by Rooting Stimulator, Shading, and Root Pruning During Transplanting to Hydroball for Hydroculture

Maintaining foliage plants by hydroculture system using hydroball provides several advantages such as the convenience in watering and clean image. To maintain foliage plants using hydroculture system, the plants should be transplanted to hydroball after removing commercial medium. In the present experiment, rooting response of nine foliage plants to IBA concentration, shading degree (light intensity), root cutting degree were investigated to improve the rooting of the plants when transplanted to hydroball for hydroculture. The foliage plants used for this experiment were Aglaonema brevispatha 'Thai Snowflakes', Ardisia pusilla, Codiaeum variegatum 'Punctatum Aureum', Dracaena sanderiana 'Victoria', Podocarpus macrophyllus var. maki, Schefflera arboricola 'Hongkong', Epipremnum aureum 'Enjoy', and Epipremnum aureus Engl. Plant species used were changed according to each experiment. Four plants (Ardisia, Codiaeum, Dracaena, and Schefflera) among 6 foliage plants showed 4 times more number of roots compared with that of control when dipped into IBA 1,000-2,000 mgㆍL-¹. In P. macrophyllus, IBA showed no improving effect in rooting, but Rootone (a commercial rooting promoter) 3 times higher more number of roots than that of control. To investigate the rooting response of foliage plants to shading degree, cutting bed were shaded at 3 shading levels of 50 (160 micromoleㆍm-²ㆍs-¹), 70 (96 micromoleㆍm-²ㆍs-¹), and 90% (32 micromoleㆍm-²ㆍs-¹) with shading net. Six plants (Ardisia, Codiaeum, Dracaena, Podocarpus, Schefflera, E. aureus 'Enjoy', and S. aureum) showed higher root number as the shading degree decreased. However, Aglaonema showed no significant difference in rooting between different shading degrees. Aglaonema was only one species showing the best results in rooting when the roots were cut leaving 2-3 cm, resulting in 3 higher more roots than other treatments (cutting all roots or no cutting). Plants showing similar root number regardless of cutting degree were Codiaeum, Dracaena, Schefflera, and Scindapsus 'Enjoy'. Podocarpus and both cultivars of Scindapsus showed more root number when the roots were not pruned at all or 2-3 cm of roots was left.