Optimization of an improved, efficient and rapid in vitro micropropagation protocol for Petunia hybrida Vilm. Cv....

An efficient protocol for in-vitro propagation of an important ornamental crop, Petunia hybrida Vilm. Cv. "Bravo" was developed. The explants that were used to carry out the experiment were Leaf segments, nodal segments and shoot tips. Nodal segments recorded highest per cent asepsis followed by shoot tips and leaf segments. Asepsis was found to be highest when the explants were sterilized with Fungicide (Carbendazim) 0.02% for the duration of 30 min followed by 0.1% HgCl₂ for duration of 10 min and then ethanol 70% for 10 s. Longer duration of the sterilant treatment showed more necrotic effects on the explants, thus mercuric chloride treatment when given for 5 min proved to be more effective in terms of survival of the explants. Maximum establishment per cent was recorded in Murashige and Skoog (MS) media fortified with BAP (1.5 mg L^-1) and IBA (0.5 mg L^-1) in shoot tips and nodal segments, i.e. 97.90 and 95.74% respectively. Callus was efficiently induced and developed when PGR amalgamation of BAP (0.1 mg L^-1) and 2,4-D (1.5mg L^-1) was used. Kinetin at the concentration of 2.0 mg L^-1 along with IBA at 0.5mg L^-1 recorded highest callus regeneration in both leaf and internodal segment derived callus. Maximum proliferation percent of shoots (97.90%), highest number of shoots (20.50 explant^-1) and maximum length of shoot (2.70 cm) was recorded in PGR combination of IBA and BAP both at 0.5 mg L^-1 concentration level. Rhizogenesis was recorded to be highest in the MS media containing IBA 1.00 mg L^-1. Best hardening media which recorded maximum survival per cent 92.50% was noticed on the media formulation comprised of equal ratio of perlite and vermiculite mix, under poly house conditions.