Abstract Efficient plant micropropagation depends upon a number of factors one of which is the type and concentration of exogenously supplied carbon sources in the medium. This study tested several different sugars as carbon source on the efficiency of shoot proliferation and in vitro rooting of common ninebark (Physocarpus opulifolius (L.) Maxim.). Fructose, glucose, maltose and sucrose were tested at concentration ranging from 0–50 g dm^-3. The dry matter content, reducing sugars and sucrose in shoots were related to sugar concentrations in the medium and so was the rate of adventitious root formation. Sucrose did not stimulate shoot proliferation and glucose was completely ineffective in rooting induction. The highest number of shoots was produced on the fructose-containing medium. The concentration of 30 g dm^-3 appeared to be optimal; the rate of proliferation at 30 and 40 g dm^-3 were in fact similar, but the former produced a more favorable shoot length. The number of adventitious roots produced per shoot increased with increasing fructose concentration up to 30 g dm^-3. Fructose can be therefore recommended as the best C-source for the in vitro shoot proliferation and rooting in common ninebark.

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