Influence of nitrogen and phosphorus on flowering, N and P content of African marigold, Tagetes erecta L var Cracker Jack

A field investigation was conducted to study the influence of nitrogen and phosphorus on flowering, N and P content of African marigold. The results revealed that among four levels of nitrogen highest level of nitrogen (200 kg N/ha) took significantly minimum days to complete flowering (50.66 days) and the treatment of 150 kg N/ha recorded significantly higher number of flower heads per plant (28.42), size of the flower head (5.59 cm), fresh weight of the flower heads per plant (71.25 g) and yield (11.11 t/ha). The days to full flowering were earlier (51.41 days) in the treatment without phosphorus. However number of flower heads per plant (28.30), size of flower head (5.74 cm), fresh weight of the flower heads per plant (69.65 g) and yield (10.80 ton/ha) was higher in the treatment of 200 kg P/ha. While studying the interaction effect of nitrogen x phosphorus the combination of highest level of nitrogen (200 kg N/ha) without phosphorus recorded early flowering (50.00 days). Number of flower heads per plant (31.83), fresh weight of the flower heads per plant (75.13 g) and yield (11.65 t/ha) were higher in treatment combination of 200 kg N/ha and 200 kg P/ha. The content of nitrogen and phosphorus and their combinations increased as their levels increased. Significant and positive correlation was observed between yield and other parameters.