Abstract:

The transgenic acceptor regeneration system and the genetic transformation system are important in the plant transgenic manipulation. This study explored the optimal medium of embryoid induction and the optimal antibiotic selection concentrations of shoot and root regeneration of Chrysanthemum morifolium cv. ‘Huaihuang’. CmTGA1, a disease- resistant gene, was transformed into ‘Huaihuang’ by using homeosis and regenerated new lines. Explants were cultured for 15 d on MS basal medium supplemented with 1.5 mg·L⁻¹ IAA, 0.5 mg·L⁻¹ 6-BA and 1.0 mg·L⁻¹ 2,4-D, then transferred to the meristematic medium without 2,4-D and cultured for 8−10 weeks, finally the regeneration bud was induced for 2 to 3 weeks on the developed medium. 86% of explants gained regeneration buds from embryoids. The selected concentration of hygromycin B was 5.0 mg·L⁻¹ for shoot regeneration and 4.5 mg·L⁻¹ for rooting. The integration of CmTGA1 into the genome of the transformation lines was confirmed by semi-quantitative PCR and real-time quantitative PCR. Finally, the transgenic acceptor regeneration system with indirect somatic embryogenesis was established successfully for Huaihuang, and this technology may lay the foundation for solving some production problems such as serious disease infection and germplasm degradation by genetic engineering methods.

Key words: Chrysanthemum morifolium cv. ‘Huaihuang’, indirect somatic embryogenesis, regeneration system, transformation