Transformation of alfalfa with smt1 gene mediated by agrobacterium

Selenium is an essential micronutrient for normal functions of alfalfa （Medicago sativa）. The scarcity of selenium would depress growth of alfalfa and decrease nutritional values of alfalfa hay, which is one of the key problems of low quantity and quality of alfalfa hay in China. Development of transgenic plants with the seleniumtolerant genes is a potential pathway to improve selenium level in alfalfa. The gene smt1 cloned from Astragalus bisulcatus was introduced into alfalfa Zhongmu No. 1 plants mediated by agrobacterium. 32 transgenic plants were obtained after the screening of 3 mgL-1 Hygromycin. 18 out of 32 were amplified bands consistent with smt1 gene size by PCR and 2 were positive in the gene expression identified by RTPCR. Results indicated that the smt1 gene had been transformed successfully and expressed normally in alfalfa.