Rapid in vitro propagation of grapevine cv. Crimson Seedless-Influence of basal media and plant growth regulators

Abstract: Grapevine genotypes differ in tissue culture requirements and thus require optimized culture conditions for in vitro propagation. Single node segments of Crimson Seedless cultured on six different basal media i.e. Murashige and Skoog (MS), Eriksson (ER), Gamborg (B5), Nitsch and Nitsch (NN), Woody plant medium (WPM) and Chee and Pool (C₂d) showed different percentage of shoot initiation and morphogenetic responses. The maximum shoot initiation (90.0%) was observed in MS medium. Except ER, all other media induced rooting at the base of nodal segments in varying percentages though number and quality of roots and their establishment on transfer to pots varied greatly. WPM induced the maximum rooting in nodal segments (69.1%) with establishment rate of 100.0%. Induction of multiple shoots in nodal segments was achieved on inclusion of 6-benzyl adenine (BA) (8.87 uM) and indole-3-butyric acid (IBA) (1.48 uM) in the MS medium. In second sub-culture i.e., at 90 days, shoot bud proliferation could be increased many fold on transfer of these initial shoot clumps to glass bottles instead of culture tubes. The maximum average number of primary shoots (19.5 per explant) was achieved on MS with BA (8.87 uM) and IBA (1.48 uM). Elongation of shoots was achieved on MS with BA (2.22 uM) + a-naphthalene acetic acid (NAA) (0.54 uM). Induction of ex vitro rooting and establishment of rooted shoots after transfer to pots was achieved in different efficiencies when shoots were given pulse treatment of indole-3-acetic acid (IAA) or IBA or NAA at 57.08, 49.0 and 53.71 uM, respectively, for 5 or 10 min. Survival of in vitro and ex vitro-rooted shoots on potting was 90.0 and 100.0%, respectively.