EFFECT OF THE BIOPREPARATION "GOTEO" ON ROOTING OF HYDRANGEA STEM CUTTINGS (HYDRANGEA PANICULATA SIEBOLD 'LIMELIGHT' AND VANILLE FREISE® 'RENHY')

The aim of this work was to compare the effects of biostimulator "Goteo", indole-3-butyric acid (IBA), and commercial rooting powder "Rhizopon AA" on rooting of stem cuttings of Hydrangea paniculata 'Limelight' and VANILLE FREISE (R) 'Renhy' as well as to study some biochemical aspects of their action. "Rhizopon AA" as well as the water IBA solution effectively stimulated rooting. The results of application of 0.2% water solution of "Goteo" were comparable to those of the synthetic auxin. The use of "Goteo" resulted in an increased content of chlorophyll, indole-3-acatic acid (IAA) and total soluble sugars in cuttings while the levels of free amino acids and polyphenolic acids were reduced relative to untreated controls in both hydrangea cultivars. A treatment with "Rhizopon AA" also resulted in an increased IAA content and a reduction in free amino acids in both cultivars. The increase in chlorophyll content was observed in VANILLE FREISE (R) 'Renhy', while the decrease in polyphenolacids in the 'Limelight'. Total soluble sugars did not change. The use of the water solution of IBA contributed to an increase in chlorophyll and IAA and a decrease in free amino acids in both cultivars. The decrease in polyphenolacids occurred in the 'Limelight', while the increase in the total sugars in VANILLE FREISE (R) 'Renhy'. The above results show that the auxin-based preparations and biostimulators generally act in a comparable way during rhizogenesis in hydrangea and may be used interchangeably for rooting of stem cuttings in woody plants.