Agrobacterium - Mediated transformation and regeneration of Pharbitis nil

Abstract

A reliable method for the transformation of Pharbitis (Ipomoea) nil is described for the first time. Somatic embryos derived from immature zygotic embryos were used as starting material. These were transformed with Agrobacterium tumefaciens strain GV3101 (pMP90), which harbored the plasmid pIG121Hm that included genes for β- glucuronidase (GUS), kanamycin resistance and hygromycin resistance. Infected embryos were induced to undergo secondary embryogenesis and kanamycin-resistant embryos were selected and allowed to develop into plantlets. All transgenic plants were morphologically normal and fertile. Stable integration and expression of the transgene for GUS were confirmed by histochemical and Southern blotting analysis. Expression of the intron-containing reporter gene for GUS under control of the 35S promoter of cauliflower mosaic virus (CaMV 35S) was detected after staining. Southern hybridization confirmed the stable inheritance of the transgene for GUS.