Callus culture from various explants of Gardenia jasminoides Ellis with intent to induce somatic embryogenesis in vitro

Callus was produced from leaves, petals and shoot apices of Gardenia jasminoides Ellis cultured on Murashige and Skoog's nutrient medium supplemented with various concentration combinations of an auxin (2.4-D or a-NAA) and a cytokinin (BA) and incubated either in complete darkness or in 16-h photoperiod. High callus growth rates evaluated on the basis of a visual estimation scale were observed with petal explants on medium supplemented with 2.0-4.0uM 2.4-D plus 0.1uM BA. Maximum callus growth of leaf explants was obtained in treatments containing 2.0-4.0uM 2.4-D plus 0.1uM BA in 16 hours photoperiod or 3.2uM NAA plus 0.8-1.6uM BA, 6.4uM NAA plus 0.83.2uM BA and 12.8uM NAA plus 0.2-0.4uM BA in complete darkness. The best combinations of growth regulators for callus formation on shoot apes explants were 2.0uM 2.4-D plus 0.1uM BA, 8.0uM 2.4-D plus 1.0uM BA, 4.0-8.0uM 2.4-D plus 0.1uM kinetin and 2.0uM 2.4-D plus 0.1uM 2iP. Rhizogenesis was very common with leaf explants during primary culture, particularly on treatments containing low BA concentrations (0.0-0.4mM). Callus derived from leaf explants produced globular somatic embryos within ten weeks following transfer from conditioning medium supplemented with 0.2-0.8uM NAA plus 3.2-12.8uM BA in all possible combinations in 16 hours photoperiod to half strength MS induction medium supplemented with 0.1uM NAA plus 1.0uM BA in 16 hours photoperiod. Differentiation of nodule-like outgrowths was induced in shoot apex explants either from the epidermal cells or indirectly via intervening callus. Callus derived from petal explants differentiated organised green globular structures within six weeks following transfer from MS nutrient medium with various combinations of 2.4-D and BA incomplete dark, to half strength MS nutrient medium supplemented with either 1.0 or 5.0uM BA in 16 hours photoperiod. Addition of 0.4g/l L-glutamine to the basal medium, favoured differentiation of green globular structures. Growth into whole plants did not occur