Effect of different concentration of indole-3- butyric acid and cutting size on rooting in gmelina (Gmelina Arborea Roxb.)

Gmelina is a multipurpose tree species and naturally found in dry and moist deciduous forest. The success of large-scale plantation program fully depends on the planting of quality plant stock. Clonal propagation of selected genotypes will help to capture the full genetic potential of existing variation. The present experiment was conducted to investigate the effect of different concentration of Indole-3-Butyric Acid and size of cuttings for rooting and sprouting behavior of Gmelina cuttings. Rooting experiment was conducted in a completely randomized block design with four replication. The shoot cuttings were collected from the vegetative multiplication garden and graded based on size into different diameter classes. The four diameter classes viz., 10mm,10-20mm,20-30mm and >30mm were formulated to estimate the potential of shoot/ root regeneration. Shoot cuttings were treated with different concentration of IBA viz., 500, 1000, 2000, 3000 and 4000 ppm to assess the effect of IBA on rooting and survival. The cuttings were planted in the root trainer containing the rooting substrate of vermiculite. The root trainer was placed inside the low-cost polytunnel located inside the 75 per cent shade net. The observation of rooting and sprouting parameters were recorded 75 after planting into a rooting substrate. Among different concentration, IBA@ 2000 ppm and 10-20 mm diameter class of cuttings recorded higher value on rooting, sprouting and survival percentage.