Objective  Appropriate methods for efficient tissue disinfection, explant induction, and culture medium formulation were established for a high-performance program to propagate pyrethrum.

  Method  Unopened flower buds of white flower pyrethrum were sterilized and used as explants on an MS solid medium for the experiment. Effects of various plant growth regulators on bud induction, proliferation, and rooting of the seedlings were monitored.

  Result  The optimum conditions for disinfecting the explants were found to be a treatment of 75% alcohol for 30 s followed by one of 0.10% mercuric chloride solution for 10 min and another of 15% hypochlorite for 15 min. For bud induction, the choice medium was formulated with MS + 2.0 mg·L⁻¹ 6-BA + 0.5 mg·L⁻¹ TDZ+ 0.2 mg·L⁻¹ IBA; for bud proliferation, MS + 1.0 mg·L⁻¹ 6-BA + 0.1 mg·L⁻¹TDZ + 0.1 mg·L⁻¹ IBA; for rooting, MS + 0.1 mg·L⁻¹ IAA + 0.1 mg·L⁻¹ IBA; and for transplanting seedlings, peat:perlite at 6:1. A survival rate greater than 90% as well as adequate transplanting was achieved.

  Conclusion  The newly developed in vitro regeneration system materially lessened the pressure of the recently encountered white flower pyrethrum germplasm degradation. In addition, a supply of high-quality seedlings could be assured with the proposed propagation program.