Effect of time and concentrations of gibberellic acid application on growth and flowering of african marigold (Tagetes erecta l.) CV. Pusa Narangi

An experiment was carried out to assess the effect of time and concentrations of gibberellic acid application on growth, flowering and yield of African marigold. The foliar application of gibberellic acid was applied in five concentrations (0 ppm, 100 ppm, 200 ppm, 250 ppm, 300 ppm) at two stages of growth i.e. (20 DAT and 40 DAT). Among the treatments, maximum plant height (68.19 cm), plant spread east to west (40.53 cm) and plant spread north to south (41.07 cm), number of branches per plant (32.28), duration of flowering (71.99 days), maximum weight of flower (9.30 g), number of flowers per plant (45.04), yield of flowers per plant (427.87 g), yield of flowers per plot (6002.45 g) and yield of flowers per hectare (234.47 q/ha) were recorded with T9 (GA3 300 ppm at 40 DAT) and minimum values of these parameters exhibited by control (T₁). However, earlier flower bud initiation (38.76 days), days taken to opening of first flower (48.14 days) and days taken to opening of 50% of flowering (56.17 days) were recorded in treatment T₅ (GA₃ 300 ppm at 20 DAT) while, maximum values of these parameters were noted under control (T₁).