Abstract: In order to improve the S. androgynus cold tolerance, genetic transformation system of S. androgynus was established in this study. The cDNA Mpafp149 of Microdera punctipennis dzungarica was used as target gene to obtain the cold tolerant transgenic S. androgynus plants. The stems of S. androgynus were transformed with Agrobacterium tumefaciens EHA105 strain which harbors plasmid pCAMBIA-1302-Mpafp149.The transformation parameters of Agrobacterium concentration, pre-culture period, co-culture period, immersion time and concentrations of antibiotics(hygromycin) were optimized selectively. The results showed that the better physiological and transforming condition was pre-cultured and co-cultured for 2 days respectively, immersed in OD₆₀₀ 0.2~0.25 liquid bacterium for 8 min. It was primarily proved by PCR that the Mpafp149 was integrated into the Sauropus androgynus and the T₀ transgenic S. androgynus plants were obtained successfully.

Key words: Sauropus androgynus, insect antifreeze protein gene, agrobacterium mediated, genetic transformation