Elicitation is based on signal (elicitor)-induced expression of genes, which subsequently results in increased synthesis of secondary metabolities in plants and in vitro cultures. Elicitors do not usually influence gene activity directly but by means of transmitters of the signal, which include primarily calcium ions. The paper examined the effect of four concentrations of calcium ions on the production of anthracene derivatives by means of the callus and suspension cultures of Rheum palmatum L. (Polygonaceae), which was elicited by an abiotic elicitor – a 20 µM solution of lead dichloride. The culture was cultivated on a Murashige-Skoog medium with an addition of 10 mg.l-1 of α-naphthylacetic acid. It follows from the results that the maximal content of anthracene derivatives, determined by the photometric determination according to PhBs 4, was demonstrated in the suspension culture after 24-hr administration of the elicitor and a 10 mM calcium chloride solution. In comparison with the control and elicited groups, the production was stimulated by 44 % and 17 %, respectively. After an addition of calcium ions to the elicited callus culture, no positive influence on the production was observed.

        Key words: Rheum palmatum L. in vitro – anthracene derivatives – abiotic elicitation – calcium ions