GROWTH AND FLOWERING OF KALANCHOE 'RAKO' AS AFFECTED BY CONCENTRATION OF PACLOBUTRAZOL AND UNICONAZOLE

Effect of concentration of paclobutrazol and uniconazole applied as a foliar spray on the growth and flowering of kalanchoe (Kalanchoe blossfeldiana) ‘Rako’ was examined. In experiment 1 (summer), 240 mL∙m^-2 of 20, 40 or 80 mg∙L^-1 paclobutrazol and of 10, 20 or 40 mg∙L^-1 uniconazole was applied at each application. In experiment 2 (winter), 210 mL∙m^-2 of 10, 15, 20, or 25 mg∙L^-1 paclobutrazol and of 5, 10, 15, or 20 mg∙L^-1 uniconazole was applied at each application. Both materials were applied twice after pinching. For all applied concentrations, plant size, stem internode length, flower stem length, and stem diameter were reduced. Increasing concentration produced smaller plants linearly. However, all concentrations of paclobutrazol and 5 mg∙L^-1 uniconazole increased number of florets. Uniconazole was more effective than paclobutrazol at similar concentrations in reducing stem growth. Plants treated with uniconazole had xylem vessels and phloem cells suppressed in both length and width. Results indicate that the optimum concentration was 10 mg∙L^-1 paclobutrazol and 5 mg∙L^-1 uniconazole.

Download Adobe Acrobat Reader (free software to read PDF files)