Title: Effect of nitrogen and phosphorus on growth, flowering and flower yield of China aster (Callistephus chinensis L. Nees) cv. POORNIMA
Abstract: The experiment was laid out in Factorial Randomized Block Design.The treatments comprised of two factors (1) nitrogen with four level viz., 150 kg N ha -1 (N 1 ), 200 kg N ha -1 (N 2 ), 250 kg N ha -1 (N 3 ), 300 kg N ha -1 (N 4 ) and three levels of phosphorus i.e. 100 kg P 2 O 5 ha -1 (P 1 ), 150 kg P 2 O 5 ha -1 (P 2 ), 200 kg P 2 O 5 ha -1 (P 3 ) with three replications.Both the highest levels of N and P significantly improved growth parameters i.e. plant height (51.56 cm), plant spread (328.67 cm 2 ), secondary branches per plant (17.67), fresh weight (137.22 g) and dry weight (69.78 g) in treatment N 4 (300 kg N ha -1 ) whereas, in case of phosphorus the plant height (47.08 cm), plant spread (316.00 cm 2 ), number of branches per plant (16.92), fresh weight (132.00 g) and dry weight (72 g) was noted in treatment P 3 (200 kg P 2 O 5 kg ha -1 ).Maximum flowering span (79.11 days), number of flowers per plant (24.78) and yield of flowers (22.67 t ha -1 ) were registered in 300 kg N ha -1 treatment.Similarly, maximum flowering span (71.58 days), number of flowers per plant (23.58) and yield of flowers (22.08 t ha -1 ) were registered in P 3 (200 kg P ha -1 ).Thus, cultivation of China aster in medium black soil, the fertilizer application at the rate of 300 kg N ha -1 in two splits (first half as basal application and remaining half at 30 days after transplanting) and 200 kg P 2 O 5 ha -1 as basal dose has been found the best.