PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

Bambusa vulgaris is an economically important bamboo species valued for its rapid growth and diverse industrial, environmental, biotechnological and ornamental applications. However, for this multipurpose bamboo species, large-scale propagation through conventional methods is constrained by irregular flowering, poor seed availability and low propagation efficiency. Although several studies have reported in vitro propagation protocols, there remains a lack of standardised and reproducible media compositions that consistently achieve high establishment, shoot multiplication, rooting and successful acclimatization. Furthermore, limited information is available regarding the genetic fidelity of tissue culture-derived plants, highlighting the need for molecular validation to ensure clonal uniformity. The present study aims to standardise the culture media for in vitro establishment, optimise media composition for efficient shoot multiplication, rooting, to develop a reliable hardening protocol for regenerated plantlets and to assess the genetic uniformity of regenerated plants using ISSR molecular markers. Nodal explants of Bambusa vulgaris were surface sterilized and cultured on Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of plant growth regulators for shoot induction, multiplication, rooting and hardening. The highest explant survivability (84%) was achieved using 70% ethanol, Tween-20, 1% Bavistin, 0.1% HgCl₂ and antibiotics. Maximum shoot initiation (88%) was obtained on MS medium supplemented with BAP (2.5 mg/L^-1), while the highest shoot multiplication was recorded on solid MS medium containing BAP (2.0 mg/L^-1) and kinetin (0.5 mg/L^-1). Root induction was optimized on MS medium supplemented with NAA (3.0 mg/L^-1) and IBA (0.5 mg/L^-1), resulting in 80% rooting. The highest acclimatization success (80%) was achieved under H2 hardening conditions. Genetic fidelity analysis using ISSR markers showed that 8 of the 16 primers screened produced clear and reproducible monomorphic banding patterns identical to the mother plant, confirming the genetic uniformity of the regenerants. The standardized protocol provides a reliable system for germplasm conservation and the production of quality plant material of Bambusa vulgaris.