Effects of Cr⁶⁺ on Seed Germination and Seedling Physiological Characteristics of Salvia miltiorrhiza Bunge

To clarify the effects of heavy metal Cr⁶⁺stress on seed germination, seedling growth, and physiological indicators of Salvia miltiorrhiza Bunge. Different concentrations of K₂Cr₂O₇ with 0, 50, 100, 150, 200, 250 mg/L were used to treat Salvia miltiorrhiza Bunge seeds, and measure indicators such as seed germination rate, seedling root length, fresh weight, chlorophyll content, and stress resistant enzyme activity. The results showed that with the increase of chromium concentration, the germination rate of Salvia miltiorrhiza seeds, root length, fresh weight, and chlorophyll content of seedlings decreased, the POD activity of Salvia miltiorrhiza seedlings significantly increased, CAT activity first increased and then decreased, SOD activity gradually decreased, and the content of proline and MDA increased. Cr⁶⁺had significant stress and toxicity effects on the germination of Salvia miltiorrhiza seeds and seedling growth, and the growth of seedling roots was most severely affected by Cr⁶⁺stress.