The UE-imposed restrictions on the manufacture and use of plant protection chemicals impose on the nurseryman the need to screen for new substances that are environmentally friendly and yet effective in the production of plant material. Biopreparations may constitute such a group as they contain substances that have little environmental impact. This study evaluated biopreparation AlgaminoPlant for its effect on rooting of stem cuttings in Physocarpus opulifolius ‘Dart’s Gold’ and ‘Red Baron’ during the vegetative seasons 2010 and 2011. During rooting, cuttings were sprayed once, twice or three times with the water solutions of the biopreparation AlgaminoPlant (0.2%). To evaluate its effectiveness relative to the current treatments routinely used in the nursery production, some cuttings were treated with a rooting powder containing a synthetic auxin IBA or sprayed with a water solution of IBA. The best results were obtained with the IBA solution, however, biopreparation also positively affected rhizogenesis in ninebark. Biopreparation also affected the chlorophyll a+b, reducing sugars, free amino acids and polyphenolic acids contents in leaves of cuttings but its effects varied depending on a cultivar.

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