[In vitro selection and characterization of methionine-resistant variant in Astragalus melilotoides Pall]

A variant cell line of Astragalus melilotoides Pall. resistant to 14 mmol/L methionine was selected from calluses via mutagenesis with sodium azide. The plantlets were induced from the variant calluses. The regenerated variant plants were transplanted in soil and had set seeds. After the variant calluses had been cultured for 25 days in the medium containing 15 mmol/L methionine, the relative growth rate was 10.2 folds of the control's. Free amino acids of the aspartate family in the variant cell line increased obviously in comparison with the control. Analyses of SDS-PAGE pattern and isozyme pattern of peroxidase revealed the differences between the variant plants and the control's.