Development of an efficient protocol for plant regeneration from nodal explants of recalcitrant bamboo (Bambusa arundinacea Retz. Willd) and assessment of genetic fidelity by DNA markers

The present study describes an efficient method for in vitro plant regeneration in B. arundinacea through axillary shoot bud proliferation. Nodal explants were excised, cultured on MS medium containing different concentrations of 6-benzylaminopurine (BAP), kinetin (KIN) (0.5–5.0 mg l⁻¹) alone and/or in combinations with KIN/BAP (0.5 mg l⁻¹). The highest frequency (91.5 %) of multiple shoot bud induction with maximum number of shoots (85 shoots/explant) was noticed on MS medium + 3.0 mg l⁻¹ BAP + 0.5 mg l⁻¹ KIN. The regenerated multiple shoots were elongated on MS medium + 4.0 mg l⁻¹ KIN + 2.0 mg l⁻¹ gibberellic acid (GA₃) with maximum shoot length (4.9 cm). The elongated shoots were transferred to MS medium containing indole-3 butyric acid (IBA; 0.5–5.0 mg l⁻¹) alone and/or in combination with 0.5 mg l⁻¹ KIN and BAP. Highest frequency of rooting (75 %) was obtained on half-strength MS medium + 2.0 mg l⁻¹ IBA + 0.5 mg l⁻¹ KIN. After hardening, the plantlets were shifted to the green house and subsequently established in the field conditions with 90 % survival rate. random amplified polymorphic DNA (RAPD) markers were used to evaluate the genetic stability of the regenerants. RAPD profiles generated from the regenerated plants were found to be monomorphic, similar to the control. Results confirmed that the regenerated plants were true-to-type in nature and the developed micropropagation protocol could be used for large scale plant production of B. arundinacea.