Establishment of a tissue culture system with adventitious bud regeneration for the new raspberry germplasm 'autumn–winter yellow raspberry'

To establish and improve the tissue culture system of 'Autumn–Winter Yellow Raspberry', this study optimized the combinations of plant growth regulators for shoot proliferation and rooting, compared transplanting performance of plantlets under different culture durations, and preliminarily established an adventitious bud regeneration system. The optimal proliferation medium was Murashige and Skoog (MS) with 0.6 mg L⁻¹ 6-benzylaminopurine (6-BA), 0.3 mg L⁻¹ indole-3-butyric acid (IBA) and 30.0 g L⁻¹ sucrose, pH = 5.9. The optimal rooting medium was modified 1/2MS with 0.8 mg L⁻¹ IBA and 30.0 g L⁻¹ sucrose, pH = 5.9, and the best transplant survival rate was obtained after 30 d of culture in this rooting medium. When leaf explants were cultured on MS with 1.0 mg L⁻¹ thidiazuron (TDZ) and 30.0 g L⁻¹ sucrose, pH = 5.9 with the adaxial side down in darkness for 21 d, and then transferred to light, the induction rate exceeded 90% after 20 d. These results provide a basis for further breeding and functional research of this germplasm.