Assessment of colchicine sensitivity in African marigold (Tagetes erecta) var. Pusa Narangi Gainda

The present experiment was carried out to determine colchicine sensitivity in African marigold (Tagetes erecta)var. Pusa Narangi Gainda to various levels of colchicine (0.00, 0.02, 0.04, 0.06, 0.08 and 0.1%) at different duration of soaking (0, 1, 2 and 3 hours). The experimental results indicated that the effect of colchicine concentration and duration of treatment has a significant effect on morphological parameters of African marigold. Result showed gradual and significant reduction in germination percentage (40%), survival of seedlings (9%), shoot length (6.1cm), root length (3.2cm), leaf length (3.25cm) and leaf width (1.35cm) with the increase in concentration of colchicineat 0.1% for 3 hours of soaking. The probit curve analysis based on mortality percentage of treated seeds revealed, the LD50 dosage of colchicine to be 0.11% with a soaking duration of one hour for African marigold var. Pusa Narangi Gainda.