Initiation and Multiplication of Petunia Explants (Petunia hybrida L.) in Vitro Propagation

This experiment was carried out in the Laboratory of Plant Cells and Tissue Culture of the Horticulture and Landscaping Design Department/College of Agriculture/University of Kirkuk-Iraq, to study micropropagation of Petunia plant ( Petunia hybrida L.), different plant parts (Explants) were used (shoot tips and nodes) from petunia plants grown in the Agricultural Research and Experiments Station Al-Sayada. The explants were cultured on MS medium supplemented with Benzyl adenine at (0.0, 0.5, 1.0, 1.5, and 2.0) mg.l -1 and Kinetin at (0.0, 2.0, 4.0, 6.0, and 8.0) mg.l -1 at initiation and multiplication stages, Data refers highest response (100%) were obtained from all treatments of BA and Kin under study at initiation stage. highest number of branches, Length of the longest branch, total leaves number,(3.00 branches.part -1 , 3.15cm, 31.40 leaves.plantlet -1 ) respectively obtained from culture on MS medium supplemented with BA at 1.0 mg.l -1 , while the best rate of leaves number/longest branch 14.87 leaves.branch. -1 at 1.5 mg.l -1 . While in multiplication stage after 8 weeks, number of branches and number of leaves/longest branch (8.25 branches.part -1 , and 31.37 leaves.branch -1 ) respectively were obtained from culture on medium supplemented with BA at 1.5 mg.L -1 . Length of the longest branch and total leaves number (5.27cm and 52.90 leaves.plantlet -1 ) respectively were obtained from culture on medium at 1.0 mg.L -1 . Moreover, the highest number of branches, Length of the longest branch, total leaves number, and number of leaves/longest branch (3.25 branches.part -1 , 23.00 leaves.plantlet -1 , and 15.75 leaves.branch -1 ) respectively obtained from culture on MS medium supplemented with Kin at (6.0) mg.L -1 at initiation stage, while Length of the longest branch 3.11 cm were obtained by Kin at 4.0 mg.L -1 . For the multiplication stage, the rates were (4.00 branches.part -1 , 34.33 leaves.plantlet -1 , and 19.66 leaves. branch -1 ) respectively obtained from Kin at 4.0 mg.L -1 , while Length of the longest branch (4.12cm were obtained from culture on medium supplemented with Kin at 2.0 mg.L -1 .