Chemical Mutagens and Their Impact in Modifying the Growth of Chrysanthemum (Dendranthema grandiflorum) var. Flirt

The present research was conducted at Experimental Farm, Kharora, Department of Agriculture, Mata Gujri College, Fatehgarh Sahib, Punjab, during autumn of the year 2023-2024. The study was carried out in a randomized block design with seven treatments and three replications. Different doses of the chemical mutagens Ethyl methanesulphonate (E.M.S.) and colchicine were utilized in the experiment, with the specific doses being T1 i.e., E.M.S. 0.75%, T2 i.e., E.M.S. 1.0%, T3 i.e., E.M.S. 1.25%, T4 colchicine 0.02%, T5 i.e., colchicine 0.03%, T6 i.e., colchicine 0.04%, and T7 i.e., control. Applying E.M.S. and colchicine treatments to rooted chrysanthemum cuttings led to significant changes in vegetative and flowering characteristics, creating variability. Both E.M.S. and colchicine treatments resulted in a significant reduction among vegetative parameters (plant height, number of branches, plant spread, diameter of main stem and number of leaves per plant) on the contrary the leaf area (65.34 cm2) increased in response to colchicine treatment and decreased in response to E.M.S. treatment compared to the control group treatment. Notably, an increase in the concentration of E.M.S. (E.M.S 1.25%) and colchicine (colchicine 0.04%) resulted in a decrease in vegetative and flowering parameters. Maximum plant height (52.00 cm), number of branches per plant (13.29), plant spread (29.39 cm2), main stem diameter (8.85 mm), and number of leaves per plant (111.22). These findings suggest that E.M.S. and colchicine can be effectively utilized to induce beneficial mutations in chrysanthemums potentially contributing to develop new dwarf plant varieties with desired traits, breeding program and scientific research to study plant development. This research highlights the importance of optimizing mutagen doses to achieve desired horticultural outcomes. Treated plants exhibit valuable ornamental traits suitable for different purposes for instance, the dwarf plants.