Enhancement of adenine sulfate and growth promoting substances on multiple shoot induction of Sangmon 'Nuan Rajinee' bamboo (Dendrocalamus sericeus Munro)

Multiple shoot induction of Sangmon 'Nuan Rajinee' bamboo was induced from a clump of 3-5 small shoots using MS medium with 1.0 mg L^‑1 BA and 0.1 mg L^‑1 TDZ supplemented with various concentrations of adenine sulfate (AdSO₄) or plant growth promoting substances, namely L-proline (LP), L-glutamine (LG), polyvinylpyrrolidone-40 (PVP-40), and ascorbic acid (AA). Our results in the first experiment showed that all concentrations of AdSO₄ were able to induce shoot multiplication ranging from 3.0 to 8.3 new shoots with no statistical difference. However, AdSO₄ at the concentration of 40 mg L^‑1 was the most appropriated for multiplying shoots growth in terms of maximum averaged shoot height (3.58 cm), as well as induced uniform shoot size with healthy green color without excreted phenolic compound. The second experiment induced multiple shoots from a clump of 3-4 small shoots using MS medium with 1.0 mg L^‑1 BA and 0.1 mg L^‑1 TDZ supplemented with 500 mg L^‑1 LP alone or combined with 500 mg L^‑1 LG or supplemented with 200 mg L^‑1 PVP-40 alone or combined with 100 mg L^‑1 AA in liquid or semi-solid medium. The results indicated that multiple shoots cultured in liquid medium supplemented either with 500 mg L^‑1 LP alone or 200 mg L^‑1 PVP-40 alone gave the averages of 4.3-5.9 healthy uniform green shoots with maximum shoot length.