Genetic Improvement of Calendula officinal through Mutation Induction using Gamma Irradiation and Chemical Mutagens

Calendulais one of the basic plants of ornamentals. It is used in various purposes as cut flowers and in gardens. They are rich with active compounds such as chlorophyll a and b, phenols, flavonoid, and carotenoids. The present study focused on mutation induction in order to improve the morphology of the plant which can increase the turnout of its market. In order to examine which mutagen will make the most noticeable and permanent improvement of the plant. For the mutagens, seeds were treated with three doses of gamma ray (2500, 5000, 7000Gy) and two chemical mutagens; colchicine and EMS; which were applied at concentrations of 1000, 3000, and 10000 ppm. With the aim to measure the plant improvement, we measured the plant morphology, its active compounds and protein profiling before and after treatments with both γ-radiation and chemical mutagen to see which one has the most effective imprint on the plant. The morphological parameters data showed the highest plant high by the two doses; gamma dose of 7000 Gy and EMS concentration 10000 ppm, while the lowest dose of colchicine (1000 ppm) made the most impact on the plant height. As for the highest number of leaves/plant, it was obtained at 5000 Gy and 10000 ppm of EMS, while 1000 ppm of colchicine had the same effect. But the number of flowers/plant was not affected by the gamma radiation and colchicine but increased significantly by 10000 ppm of EMS. Surprise, the flower diameter was not affected by EMS while decreased at 2500 Gy and 3000 ppm of colchicine. Considering the importance of flower shape, all treatments either gamma radiation or chemical mutagens showed noticeable changes. Whereas, the biochemical parameters measuring the active compounds, both Chl-a, Chl-b and carotenoids contents increased at 5000 Gy, while flavonoid increased at 2500 Gy. Although, all doses of gamma ray eliminated the phenols content. While the lowest used concentration of colchicine (1000 ppm) increased both of Chl-a, Chl-b, flavonoid and carotenoids, even though the 10000 ppm of colchicine increased the phenol. On the other hand, the highest concentration of EMS (10000 ppm) increased Chl-a and Chl-b while carotenoids, flavonoid and phenol increased at 3000 ppm of EMS. The protein-profile analysis showed fluctuation in the gene expression. The highest performance appeared at 7000 Gy of gamma treatment,1000 -3000 ppm of colchicine, while the same result was obtained by EMS at 3000 ppm.