Effects of Paclobutrazol Applications on Rooting Performance of Black Mulberry (Morus nigra L.) Hardwood Cuttings

Abstract

Cutting reproduction is the cheapest and most practical method for plants capable of clonal regeneration. However, the difficulties in adventitious root formation in black mulberry cuttings create a disadvantage for mulberry growers. This study aimed to investigate the effect of IBA and Paclobutrazol applications on the rooting ability of black mulberry hardwood cuttings. The experiment was carried out in the polyethylene greenhouse of Tokat Gaziosmanpaşa University Agricultural Research and Application Center in February 2022. As a material, hardwood cuttings prepared from one-year-old branches of breeding black mulberry trees within the body of the directorate were used. The study was set up in a randomized plot design with 3 replications and 15 cuttings in each replication. In the study, pure water as a control group, 6000 ppm IBA and doses of 1000 ppm, 2000 ppm and 3000 ppm Paclobutrazol respectively were applied to black mulberry wood cuttings separately and together. After the application, the cuttings were planted in perlite medium. The cuttings were kept in the rooting medium for 90 days and then removed; rooting rate, root number, root length and root diameter values were recorded. As a result of the study, the effect of the applications on the root number of the cuttings was not observed while the rooting rate, root length and root diameter parameters were observed. In terms of rooting rate, the best result was obtained from IBA+PBZ 1000 application (40.00%) compared to the control group (0.0%). The highest root length was determined in IBA 6000 application, and the thickest root diameter values were determined in PBZ 1000 application.