Effect of growth regulators on growth, flowering and yield of Crossandra (Crossandra undulaefolia Salisb)

An investigation was undertaken to study the effect of growth regulators on growth and flowering of crossandra (Crossandra undulaefolia Salisb) genotype Arabhavi crossandra collection-1(ACC-1) at the Department of Floriculture and Landscape Architecture, Kittur Rani Channamma College of Horticulture, Arabhavi, University of Horticultural Sciences, Bagalkot, during kharif and rabi season from June, 2015 to February, 2016. The plants were given treatments of two concentrations of Gibberellic acid (100 and 200 ppm), NAA (100 and 150 ppm), TIBA (100 and 150 ppm), Ethrel (50 and 100 ppm) and one control (water spray). Altogether there were nine treatments and were replicated thrice. The plant growth regulators were sprayed four times viz., 15, 30, 45 and 60 days after transplanting. All the treatments of growth substances registered significant effect on growth, development and flowering of crossandra. However, the plants sprayed with the Gibberellic acid (200 ppm) resulted in maximum plant height (71.10 cm), leaf area (3337.83 cm2), dry matter (88.85g), number of branches (17.63), plant spread (46.19 cm), days taken to flower spike initiation (38.00), days taken to first harvest (53.00), duration of flowering (131.00) and flower yield per plant (82.60g).