The ornamental trees, shrubs, and climber plants due to the beauty, variety, and successes experienced by researchers in production and marketing are very popular. Bougainvillea plant is a tropical shrub that the blooms with colorful flowers can be exhibited for 11 months around the year. Further, Bougainvillea brasiliensis cv.'Raerry Ice', in addition to the color brackets, has a saffron-green leaf which is very important in landscape beauty and green space. However, the asexsual propagation of this plant due to hardly rooted is a problm. There are various techniques that can be increased the asexual propagation methods effecincy. Among that, the use of the growth stimulants and rooting hormones such as synthetic auxins are critical to overcome this challenge. Therefore, this study was conduted to investigate the effect of two types of cuttings (hard wood and semi-hardwood cuttings) and different concentrations of indole butyric acid (0, 1000, 2000, 3000, 4000 mg / L) on rooting of cuting of bougainvillea cv.'Raerry Ice'. A factorial experiment was carried out in a completely randomized digsin with three replicates. The results of this study showed that IBA treatment increased rooting percentage compares to non-treated cutting, and the maximum rooting percentage was obtained in 1000 mg / L indole butyric acid treatment (86.95%). However, the lowest rooting percentage was observed in 4000 mg/L indole butyric acid treatment in semi-hardwood cuttings (66.7%). The plant growth regulator application also increased the growth parameters such as the fresh and dry weights of shoot, number of lateral branches, number of leaves, root dry weight, and number of roots, as well as physiological traits such as soluble carbohydrate and starch content at 2000 mg / l indole butyric acid. Finaly, the results of this study suggested that the use of moderate concentration of IBA (1000-2000 mg/l) on hard wood cutting enhanced bougainvillea propagation effecincy. Key words Bougainvillea, The Rooting, IBA, Hard Wood Cutting, Semi Hardwood cutting.
