Standardization of cutting parameters for adventitious rooting in Tectona grandis under protected conditions in new locality of subtropical Himalayan region

The experiment was conducted to promote the rooting in different sized shoot cuttings under protected conditions. Plant characters such as callus formation, rooting %, No. of leaves and shoot length were studied. The cuttings of all diameters under study recorded the callus formation of 70 to 93.25%. The diameter classes <20 mm registered callusing only and failed to root however, all other diameter classes registered the rooting and the highest rooting % was found to be 80% in cuttings having diameter ranging from 30–40 mm. The rooting response significantly varied with the diameter classes. However, diameter class with diameter >40mm recorded the maximum number of leaves and root length. Correlation coefficient among all the characters was positive. Overall, the cuttings having initial diameter of 30–40 mm were found to be the best of raising clonal planting stock.