Effect of nitrogen on growth, flowering and quality of China aster (Callistephus chinensis) cv. Kamini

The experiment was conducted to find out the optimum dose of nitrogen required for growth, flowering and quality of flowers in China aster (Callistephus chiensis L. Nees) cv. Kamini. The experiment was laid out with nine levels of nitrogen (N): 50 kg/ha, 75 kg/ha, 100 kg/ha, 125 kg/ha, 150 kg/ha, 175 kg/ha, 200 kg/ha, 225 kg/ha and 250 kg/ha individually and in all combination with the control (N₀P₀K₀), in a randomized completely block design with three replications. Recommended dose of phosphorous (60 kg/ha) and potassium (60 kg/ha) in the form of single superphosphate (SSP) and muriate of potash (MOP), respectively, were incorporated into the soil before transplanting. Nitrogen was applied in the form of urea in two equal split doses, i.e. at the time of transplanting and 30 days after transplanting. Significant response in vegetative growth, flowering characters and quality parameters was observed in all the treatments over the control. The growth characters, viz. plant height, plant spread, stem girth and number of secondary branches showed positive response with N 150 kg/ha over all other treatments. The commencement of flowering was enhanced by higher dose of nitrogen. The days to flower initiation significantly reduced with treatment of N 150 kg/ha followed by N 225 kg/ha. Treatment of N 150 kg/ha, also showed earliness in flowering, increased flower stalk length, flower diameter, ray florets, number of flower buds/plant, duration of flower as well as field-life. However, maximum dry weight of single flower was noticed with treatment, N 175 kg/ha. The lower doses of nitrogen did not show much influence on growth, flowering characters and quality. Thus, application of N 150 kg/ha was more beneficial to get higher yield and quality flowers.