Fig. 7.

Number (a) and total length (b) of adventitious roots formed by cuttings of ‘Rosa progress’ (RP) and ‘Natal briar’ (NB) in dependence of cutting position (top, bottom) and concentration of applied indole-3-butyric acid (IBA). Columns and bars represent mean values and SE per cultivar (n = 3, each with 20 cuttings). Numbers in the upper parts represent the mean root number (a) and mean root length in cm (b) of the two cultivars formed by the top cuttings (black letters) versus the bottom cuttings (white letters, black shade). P and C indicate significant effects of position and cultivar, respectively, at the specified level of IBA supply. *, **Significant at P ≤ 0.05, 0.01, respectively; ns, neither cultivar nor position was significant