Effects of a new light source (cold cathode fluorescent lamps) on the growth of tree peony plantlets in vitro

The effect of a new light source, cold cathode fluorescent lamps (CCFLs), on the growth of peony (Paeonia suffruticosa cv. ‘Wu Long Peng Sheng’) plantlets in vitro was examined in six different light quality ratios: 100% red (R), 80% R + 20% blue (B), 70% R + 30% B, 60% R + 40% B, 100% B and white CCFLs. Control illumination was provided by conventional heat-generating plant growth fluorescent lamps (PGFLs). All plantlet growth parameters were as effective under 70% R + 30% B (the best performing CCFL ratio) as they were under PGFLs. Chlorophyll content (a, b and total) was greater in the range of 60–80% R + 20–40% B, although in general there were no significant differences between the best performing R:B ratio and PGFLs. This study indicates that CCFLs can be used as effectively – if not better – than conventional PGFLs to micropropagate this woody ornamental.