Effects of plant hormones and light or dark culture conditions on the regeneration system of Lilium lancifolium Thunb

【Objective】In order to lay a foundation for germplasm resources development and large area popularization of Lilium lancifolium Thunb, investigated the effects of plant hormones and light and dark culture conditions on the regeneration system of lily.【Method】Using lily scales as explants, analyzing the effects on callus induction, proliferation and adventitious bud regeneration in lily scales affected by the ratio of different plant hormonesNAA, 6-BA, 2, 4-D, thidiazuron(TDZ) and 4-amino-3, 5, 6-trichloropicolinic acid(PIC)in the medium and light(illumination time:14 h/d) and dark(dark all day) culture conditions, to establish an efficient regeneration system for lily tissue culture.【Result】Compared with the control that adding no hormones (CK), mediea with different hormone combinations could significantly improve the callus induction rate of L. lancifolium (P<0.05). The combination of TDZ 0.4 mg/L+NAA 0.2 mg/Lshowed the best induction effectiveness, and the callus induction rate reached 65.57% under dark culture conditions. The scales of L. lancifolium was firstly cultured in TDZ 0.4 mg/L+2, 4-D 0.05 mg/Lfor 20 d in the dark, and then cultured in TDZ 0.4 mg/L+NAA 0.2 mg/L for 40 d in dark condition. In this case, the proliferation rate of callus was the highest, up to 2.45 times. The combination of 6-BA and NAA was more favorable to the induction of adventitious buds than the combination of 6-BA and PIC. The medium with the highest regeneration multiple was 6-BA 0.6 mg/L+NAA 0.1 mg/L, and its regeneration multiple was up to 6.08 times in dark condition. Compared with light culture, the dark culture was more conducive to callus induction and proliferation, but in the adventitious bud stage of the callus, the long-time dark culture was adverse to the growth of the bud. After incubating for 20 d in dark condition, the scales of L. lancifolium were transferred to the light condition and continue to cultivating for 40 d, the generated adventitious buds were bright green in colour, and its leaves were spreading and growing vigorously. Such adventitious buds were helpful to strong seedling and rooting.【Conclusion】Different stages of tissue culture of L. lancifolium are affected by plant. Combination of different kinds and concentrations. Dark culture is more favorable to callus induction and proliferation, the combination of dark culture and light culture is the most suitable for the regeneration and differentiation of adventitious buds.