The effect of Cutting texture type and hormonal treatment with combination rooting cofactors on rooting of yew (Taxus baccata L.)

Taxus baccata L. is one of the native and valuable species of Hyrcanian forest which is used in large scale in landscaping. In order to investigate the type of tissue cuttings (softwood, semi-hardwood and hardwood) and indole butyric acid hormones (four levels 5000, 2500, 500.0 mg L-1) in combination with rooting-cofactors (hydrogen peroxide 3% and putrescine 1 MM), a factorial experiment was conducted in a completely randomized design with four replicates. After five months from the time of cuttings, rooting percentage, root number, length of the largest root, leaf number, total chlorophyll, total phenol and number of callus cuttings were investigated. According to the results, the effect of tissue type, hormonal treatments and their interaction on the studied traits was significant. Treatment with Indole Buteric Acid (IBA) at a concentration of 5000 mg L-1 hydrogen peroxide 3% was the best treatment in increasing the rooting rate, number of roots, root length and leaflet production in semi-hardwood cuttings. The total phenol content in the hardened cuttings was less than that of soft cuttings. In the control (distilled water) treatment, cuttings produced calluses, but rooting did not take place. Among the rooting promoter materials, hydrogen peroxide was better than putrescine. The highest percentage of rooting and number of roots were related to semi-hardwood cuttings. Therefore, according to the results, the use of indole butyric acid in high concentrations and the use of hydrogen peroxide to facilitate the rooting of semi-hardwood cuttings of yew are recommended because of superiority to the control.