Effect of chemical mutagens (Ethyl methane sulphonate and colchicine) on African marigold (<i>Tagetes erecta</i>)

Tegetas errecta, commonly known as African marigold, is an annual or perennial herbaceous plant that belongs to the family Asteraceae. There is a need for mutation breeding, which allows for the development of novel cultivars that could be more valuable and highly demanding in the market. The present study aimed to find the effect of chemical mutagens on the growth and flowering of marigold cv. African marigold. The trial was statistically laid out in RBD with 3 replications and 3 replications. The treatment comprised of EMS (0.2%, 0.4%, 0.6%), (EMS 0.2% + Distilled Water 100ml), Colchicine (0.001%, 0.002%, 0.005%), (Colchicine 0.001% + Distilled Water 100ml), (EMS 0.2% + Colchicine 0.005%) and (EMS 0.6% + Colchicine 0.001%) and control. Results revealed that among all the chemical mutagens, maximum changes were in vegetative parameters like plant height, plant spread, number of leaflets, stem diameter and number of branches for the treatment T6 (Colchicine 0.002%) and T8 (Colchicine 0.001% + Distilled Water 100ml) and in flowering parameters like flower yield. The maximum changes were recorded in treatment T5 (Colchicine 0.001%). It can be concluded that chemical mutagens can enhance a plant’s vegetative growth and flowering, leading to the sustainable production of marigold. The study also revealed that colchicine and EMS might affect plant development characteristics and showed positive results in enhancing marigold's vegetative and floral parameters.