Establishment of micropropagation system of Dendrocalamus brandisii

As a famous and widely planted shoot-use bamboo species, few researches have been focused on the micropropagation of Dendrocalamus brandisii. This study established an efficient micropropagation system of D. brandisii through seeds and cutoff nodal buds from the multiple shoots in vitro. The orthogonal tests were employed to screen out the optimal disinfection time and hormone combination for multiple shoot induction, proliferation in vitro and root induction in vitro. The results showed that the optimal disinfection time was 10 min. MS medium containing 3 mg L⁻¹ BA, 0.5 mg L⁻¹ KT, 0.10 mg L⁻¹ NAA and 25 g L⁻¹ sucrose showed the highest multiplication rates, and those supplemented with 5 mg L⁻¹ BA, 0.5 mg L⁻¹ KT, 1.0 mg L⁻¹ NAA and 25 g L⁻¹ sucrose were the best for shoot proliferation. 1/2 MS medium supplemented with the hormone combination of 0.1 mg L⁻¹ IBA, and 1.0 mg L⁻¹ NAA was optimal for root induction. For plantlets regeneration from the single nodal buds of multiple shoots, the optimal medium was MS + BA 2.0 mg L⁻¹ + NAA 0.5 mg L⁻¹ for shoot multiplication and 1/2MS + BA 0.1 mg L⁻¹ + NAA 2.0 mg L⁻¹ for root induction. The optimal acclimatization medium was vermiculite + perlite (1:1). This study firstly and systematically established the micropropagation system of D. brandisii by using the seeds and nodal buds of the multiple shoots as explants. Multiple shoots induced from the cutoff nodal buds of the multiple shoots could further expand the micropropagation efficiency.