Effects of ⁶⁰Co-γ Irradiation on Seed Germination of Four Medicinal Plants

In this study, different doses of ⁶⁰Co-γ rays were used to radiate the seeds of Leonurus heterophyllus, Taraxacum mongolicum, Asiatic plantain and Perilla frutescens and the germination rate, germination potential, germination index and other indicators were also determined. The above results for further investigating the effects of ⁶⁰Co-γ irradiation on seed germination provided reference for the breeding of new varieties of these four medicinal plants. The effects of ⁶⁰Co-γ rays on the seed germination were studied, and the new varieties of the four medicinal plants were selected for reference. The results showed that ⁶⁰Co-γ radiation had a strong ability to induce mutation in the seeds of four medicinal plants, and the radiation dose was negatively correlated with the germination rate, germination potential, germination index, vigor index, seedling height and fresh weight of seeds. Among them, the negative correlation with seedling height was extremely significant（p＜0.01）. The semi-lethal dose for L. heterophyllus and T. mongolicum seeds was greater than 400 Gy, while the semi-lethal dose for A. plantain seeds was between 300—400 Gy and the semi-lethal dose for P. frutescens seeds was between 50—100 Gy.