Tissue Culture for Propagating ‘Jinfenghuang’ Tea Plants

Objective A tissue culture and rapid propagation program was established to preserve and promote the famed ‘Jinfenghuang’ Tea that widely cultivated in Wuyishan, Fujian.

Method Aseptically treated mature seeds of ‘Jinfenghuang’ Tea plants were used as the explant to evaluate various combinations and concentration of plant growth regulators (i.e., 6-BA, NAA, IBA, and GA₃) on embryo induction, axillary bud emergence, adventitious bud proliferation, and root development for optimal propagation to promote and preserve the valuable germplasm.

Result (1) The optimized medium for the embryo induction was formulated with MS + 2.0 mg 6-BA·L⁻¹ + 0.2 mg NAA·L⁻¹ to achieve a seed germination rate of 77.50%. (2) The choice medium for the emerging of axillary buds contained MS + 1.0 mg 6-BA·L⁻¹ + 0.10 mg IBA·L⁻¹ + 2.0 mg GA₃·L⁻¹ to deliver a budding rate of 82.22%. (3) The best medium for the adventitious bud proliferation consisted of MS + 2.0 mg 6-BA·L⁻¹ + 0.1 mg IBA·L⁻¹ to yield a top average bud count of 8.41. (4) For the root development, seedlings were soaked in a 100 mg·L⁻¹ sterile IBA solution for 5 min prior to transplantation onto a 1/2MS + 2.0 mg IBA·L⁻¹ medium to achieve a rooting rate of 65.55%. The regenerated plants were molecularly verified in vitro by the inter-simple sequence repeat (ISSR) techniques by showing no significant variations in two consecutive generations.

Conclusion Select plant growth regulators were included in the media for different stages of the seedling development. In the newly established rapid propagation program for ‘Jinfenghuang’ Tea, NAA was found to particularly benefit the seed germination, GA₃ the axillary bud emergence, and IBA the root induction.