Abstract

                                The experiment on the effect of nitrogen and gibberellic acid on growth, flowering and yield of China aster (Callistephus chinensis L. Nees) was carried out at Department of Horticulture, Faculty of Agriculture, Annamalai University during January to May 2001 Four levels of nitrogen (100, 200, 300 and 400 kg ha) and five levels of gibberellic acid (No spray, 100, 200, 300 and 400 ppm) were studied in factorial completely randomized design: Significant interactions were observed for plant height at final harvest stage, number of branches per plant, number of leaves per plant, flower diameter flower stem length and single plant yield, The investigation revealed that China aster crop applied with 200 kg N ha along with two sprays of 300 ppm gibberellic acid at fortnightly interval commencing from 30 DAT (N200 GA300) produced the highest yield per plant (37.85 g). The response to both nitrogen and gibberellic acid was found to be non linear.

Key words : China aster, Nitrogen, Gibberellic acid, Flower yield