Submitted to: HortScience
Publication Type: Peer reviewed journal
Publication Acceptance Date: 4/12/2009
Publication Date: 8/1/2009
Citation: Sakhanokho, H.F., Rajasekaran, K., Kelley, R.Y. 2009. Somatic embryogenesis in Hedychium bousigonianum. HortScience Vol. 44:1487-1490. Interpretive Summary: Several factors affect the in vitro regeneration response in different plant species. Among these factors is ethylene, which is known to negatively affect growth and differentiation of plants under in vitro conditions, depending on the plant species and culture stage. One way to reduce or eliminate this negative effect of ethylene is to use compounds (ethylene inhibitors) that prevent ethylene production in in vitro cultures. The objective of this study was to establish a micropropagation (based on somatic embryo production) system for the ornamental ginger Hedychium bousigonianum and determine the effect of two ethylene inhibitors, salicylic acid and silver nitrate, on in vitro tissue culture of this species. An efficient regeneration system for this ornamental ginger was established. The results showed that including salicylic acid and silver nitrate in the culture media improved somatic embryo production 4- and 3-fold, respectively.
Technical Abstract: An efficient primary somatic embryo (SE) and secondary somatic embryo (SSE) production system was developed for the ornamental ginger Hedychium bousigonianum Pierre ex Gagnepain. Addition of two ethylene inhibitors, salicylic acid (SA) and silver nitrate (AgNO3), to the culture media improved the system. Callus was initiated and proliferated on a medium containing MS basal salts supplemented with 9.05 µM 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.6 µM kinetin. Friable callus was transferred to a liquid medium containing MS basal salts, B5 vitamins, 0.6 µM thidiazuron (TDZ), and 8.9 µM 6-benzylaminopurine (BA) to induce somatic embryogenesis. The effects of various concentrations of SA (0, 25, 50, 75, 100, 125, 150 µM) and AgNO3 (0, 10, 20, 30, 40, 50, 60 µM) on callus growth, SE, and SSE development was further evaluated. The rate of callus growth decreased as the concentrations of SA or AgNO3 increased. AgNO3 and SA at all concentrations stimulated SE and SSE development better than the control even though a decrease in embryo production was observed at higher concentrations of both SA and AgNO3. The best concentrations for SA were 75 and 100 µ, while for AgNO3 they were 30 to 50 µM for both SE and SSE production.