Abstract:
The effect of sampling time and plant growth regulators on the induction of callus, somatic embryo and adventitious bud were investigated with immature embryos of Iris lacteal var. chinensis as explants. The results showed that the most feasible sampling time for immature embryos was 35-45 d after pollination, the young embryos were fully developed, but the endosperm was not completely hardened, and the young embryo was easy to dissect. The optimum medium for callus induction was MS+1.0 mg·L
-1 2,4-D+0.2 mg·L
-1 6-BA with the induction rate of 83.33%. The appropriate medium for somatic cell induction was MS+0.25 mg·L
-1 2,4-D+0.05 mg·L
-1 6-BA with the induction rate of 71.67%. The most suitable medium for adventitious bud induction and proliferation was MS+0.2 mg·L
-1 TDZ+0.05 mg·L
-1 NAA with the induction rate of 78.33% and proliferation coefficient 3.65 in this experiment. The rooting rate was more than 95% after four weeks cultivation on MS medium supplemented with 0.1 mg·L
-1 NAA. Then, the medium was washed off and explants were transplanted to sterilized vermiculite, and the survival rate was more than 95%. This study has established an efficient regeneration system of I. lacteal var. chinensis embryos, which can lay a foundation for genetic transformation and gene function analysis of I. lacteal var. chinensis.