Mung bean (Vigna radiata L.) is one of the economically important crops in Southeastern Asia and also grows in USA. Genetic transformation of mung bean has been achieved using an Agrobacterium -mediated transformation system. Two transformation methods were used in this study. With the leaf-disk transformation method, freshly cut leaf strips from young seedlings of mungbean were co-cultivated for 72 hours with either a wild-type A. rhizogenes strain 11325 or the strain containing an additional binary vector carrying the npt gene. In another method, agrobacteria were applied to wounded hypocotyls of aseptically germinated seedlings. After infection, the explants were placed on shoot induction medium. Within 3-4 weeks, shoots developed from the edges of leaf disks as well as from the inoculated sites on hypocotyls. Putatively transformed shoots were selected in vitro based on their ability to root in the kanamycin-containing medium. The npt gene fragment and a-few of T-DNA fragments from the wild-type Ri plasmid were detected in regenerated mungbean plants by Southern blot analysis. These results suggested that foreign DNAs from both the Ri plasmid and the binary vector had integrated into the genome of mung bean. These transformation systems for mung bean can now be used to introduce agronomically desirable traits into this crop for its genetic improvement.
472 PB 364 GENETIC TRANSFORMATION AND REGENERATION OF MUNG BEAN USING AGROBACTERIUM RHIZOGENES
