Auxins are main promoters of rooting. Cytokinins are considered as auxin antagonists in adventitious root formation, but their role in this process depends on a number of factors, such as concentration and the phase of treatment. Regardless of their role in rhizogenesis, cytokinins stimulate lateral shoot development. The aim of the experiment was to determine the effect of BA applied in different time of rooting and its cooperation with NAA on Portulaca cuttings and subsequent growth of plants. Stem cuttings of Portulaca umbraticola were treated with BA or BA and NAA in different concentrations and time of BA application (0; 2 and 5 days after placing in medium). BA, administered at the beginning of rooting, negatively influenced percentage of rooted cuttings, while applied two days later stimulated rooting. BA positively determined lateral shoot length and number on cuttings. Application of BA with NAA stimulated root development, but negatively affected the axillary shoot outgrowth. Considering the effect of BA treatment on rooting and branching of Portulaca cuttings the most advantages combinations occurred to be BA applied after 2 days of rooting.

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