Carnation (Dianthus caryophyllus L.) is the third most important cut flowers in the world. Tissue culture techniques offer an efficient method for micropropagation of this ornamental plant. The object of this study was to evaluate the effect of kinetin (Kin) and benzylaminopurine (BAP), on shoot multiplication of four carnation cultivars (Prado Aquila Kgr, Skimo Mogr, Mondeo Kgr and Innove Orange Bogr). Explants from shoot tips and nodal segments were cultured on MS medium supple mented with different concentrations of BAP (1, 3, 6 and 12 mg/l) or Kin (1, 3, 6 and 12 mg/l) in combination with 0.5 mg/l NAA, 30 g/l sucrose and 9 g/l agar. For rooting of regenerated shoots, the effect of IAA, IBA and NAA (1,3 and 6 mg/l) in the same medium were evaluated. The cultures were maintained at a 16-h photope riod and 25±2ºC. The results indicated that there is a significant difference among cultivars in shoot regeneration, Mondeo Kgr and Eskimo with 6 and 4 shoots re spectively were better than other cultivars (Prado Aquila Kgr and Innove Orange Bogr with 3 and 2 regenerated shoots, respectively). Effect of hormones indicated that high concentration of cytokinin increased the regenerated shoot number and hyperhydricity of them, but it decreased shoot lenght from 90 mm in medium containing 1 mg/l Kin to 30 mm in medium containing 12 mg/l BAP. Based on hyperhydricity percentage of regenerated shoots, there was a significant difference between cytokinins and cultivars. Mondeo Kgr and Prado Aquila Kgr had highest (70%) and lowest (20%) hyperhydricity, respectively and BAP caused more (80%) hyperhydricity than Kin (30%). In this investigation, the best medium for shoot multiplication and their rooting were MS medium containing 1 mg/l BAP in com bination with 0.5 mg/l NAA and MS medium containing 3 mg/l IBA, respectively.

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