The effect of explant types and led-lights on the shoot regeneration of chrysanthemum (Chrysanthemum morifoliumRamat. cv. “Jimba”) in vitro

Abstract

Light is the key factor influencing on the plant growth. Plants react to light mainly via  photosynthetic, photomorphogenetic, and phototropicresponses. In this study, the effects of  different light sources on the shoot regeneration ability of leaves and stem longitudinal thin cell

layers from the three-week-old  in vitroChrysanthemum (Chrysanthemum morifoliumRamat.

cv. "Jimba") were studied. The leaves were cut intoround discs of 0.8 cm diameter. Longitudinal thin cell layer explants, 10 mm long and 0.5 - 0.6 mm thick, were excised from the stem. These explants were cultured on MS medium supplemented with 30 g/l sucrose, 8 g/l agar, 0,5 mg/l NAA and 2 mg/l BA and cultured under different 16-h photoperiod lighting conditions of 100 % red LED (Light-Emitting Diode), 100 % blueLED, 50 % red LED + 50 % blue LED, 70 % red LED + 30 % blue LED, 80 % red LED + 20% blue LED, 90 % red LED + 10 % blue LED, fluorescent lamps, and under darkness. 70 % ofthe red LED-light combined with 30 % blue LED-light is the most suitable lighting condition for shoot regeneration directly from leaf discs and indirectly from stem longitudinal thin cell layers. The present study suggested that the shoots regenerated under light-emitting diode system could be a promising source of explants for the process of Chrysanthemum propagation.