Effect of plant growth regulators on growth and flowering characters of African marigold (Tagetes erecta)

A field experiment was carried out during rabi (winter) season of 2012–13 at Faizabad (Uttar Pradesh), India to find out the effect of various growth regulators on growth and flowering behaviour of African marigold (Tagetes erecta L.) cv. ‘Pusa Narangi Gainda’. The experiment was conducted in randomized block design with ten treatments comprising of three levels each of Gibberellic acid, GA₃ (100, 200 and 300 ppm), ethrel (200, 300 and 400 ppm) and maleic hydrazide (200, 300 and 400 ppm) replicated three times. All the vegetative and flowering characters of marigold influenced significantly due to various plant growth regulators irrespective of their doses. Among growth regulators, GA₃ 300ppm recorded maximum plant height (75.93 cm), plant spread (50.07cm), and early flower bud initiation (48 days), opening of first flower (89.87 days), duration of flowering (50.47 days), flower stalk length (8.95 cm), flowers plant⁻¹ (60.33), closely followed by GA₃ 200 ppm over other growth regulators. However, ethrel 400 ppm gave maximum branches plant⁻¹(44.73) in marigold.