This study was conducted in Plant Tissue Culture Laboratory, Agriculture
Collage, Basrah University, Basrah Governorate, Iraq during the period 23/ October/ 2013 to
23/ May / 2014. The aims of this study can be summarized to effect the source of explants
and different concentrations of Cytokinins (TDZ), Auxins (IBA) on initiation, multiplication
and rooting explants in micropropagation of dwarf gardenia (Gardenia jasminoides Ellis.)
cultivar 'Radicans', Maximum successful response of shoot tips in vitro (100%) was noticed in
MS medium enriched with different concentrations of TDZ (0.5, 1, 1.5 and 2 mg.L) in the
presence of NAA and GA3 0.2mg.L each, but the high rate of shoot number(1.8) and length
(1.18 cm) obtained on MS medium containing 1 mg.L TDZ. Where, the rate value of leaf
width and numbers were increased only on MS medium fortified with low concentrations of
TDZ (0.5 and 1mg.L). On the contrary, nodal explants cultured on same medium failed to
responding, except the ones cultured on MS medium containing 1mg.L TDZ , showed
moderate rate value of average growth responding(66. 06%). Highest shoot and leaf numbers
and leaf width recorded on MS medium containing 1 mg. L TDZ in the presence of NAA and
GA3 0.2mg.L each (4.33 shoots. explant, 6.00 leaves. explant and 1.30 cm respectively).
Whereas, highest shoot length (1.50 cm) recorded on MS medium fortified with 0.5 mg. L
TDZ. However, small amount of white brownish callus raised around the nodes grown on
medium containing 0.5 mg. L TDZ, while big amount of the same callus was recognized
around the nodes grown on MS medium containing 1.5 mg. L TDZ. Maximum root formation
rate (100%) with high number of roots (7.33/plantlet), root length (7.33cm) and number of
secondary roots (8.00. main root), were obtained within a short period (13.33 days) when the
multiplied shoots transferred to½ MS medium enriched with 4mg.L IBA compared with
another treatments (0, 1, 2, 3, 4) mg. L. Also, it was found that the length of shoots and
number of leaves were increased to (12 cm and 11.33 leaves. plantlet, respectively). |