Factors Affecting the Regeneration and Growth of Bulblets in Bulb-scale Cultures of Lilium rubellum Baker

Lilium rubellum Baker bulb-scales excised from bulbs growing in vitro were cultured at different temperatures, in various lengths of light period, or in a medium containing different concentrations of α-naphthaleneacetic acid (NAA) and 6-benzylaminopurine (BA).Temperature affected the percentage of regenerating bulb-scales, the number of bulblets per scale, and the growth of bulblets. The optimum temperature for each of the parameters was 25°C.The percentage of regenerating bulb-scales and the number of bulblets per scale were stimulated in a lighted environment, but the fresh weight of bulblets formed in this environment was lower than the weight of those formed in darkness.NAA at concentrations of 0.05 and 0.1mg/l gave a stimulatory effect on each of the parameters, but the higher concentrations suppressed bulblet formation. BA scarcely affected any of the parameters, except in the combination of 0.1mg/l BA with 1.0mg/l NAA, which enhanced the fresh weight of the bulblets.