Efficient calogenesis induction and rapid cell multiplication are fundamental requirements in plant biotechnology. The success of calogenesis is dependent on the growth medium components and the quality of explants. This work is referred to the influence of Dianthus caryophyllus L. nitrogen treatment on calogenesis induction in vitro. Carnation cuts rooted in sand pots were treated with nutrient solutions containing 5 nitrogen levels. Leaves, internodes and node explants were collected and inoculated on callus induction culture media containing Murashige & Skoog (1962) salts and vitamins, supplemented with 1 g L-1 hidrolysed casein, 2 mumol L-1 kinetin and 3 mumol L-1 2,4-D. No plant deficiency and toxicity symptoms were apparent on the treated plants during the 60 day treatment. The nitrogen treatment affected calogenesis in relation to calli fresh and dry weights. Callus fresh weigth yield was proportional to nitrogen concentration up to 267 mg L-1 for leaf explant during 30 days. Longer treatments (45 and 60 days) affected calogenesis negatively which were inversely proportional to the nitrogen concentration of the nutrient solution.
mineral nutrition; tissue culture
