Somatic Embryogenesis and Agrobacterium-mediated Transformation of Epipremnum aureum ‘Jade', Poster Board #127

This study established an efficient system for regeneration and transformation of Epipremnum aureum ‘Jade’. Leaf and petiole explants were cultured on a Murashige and Skoog basal medium supplemented with N-(2-chloro-4-pyridl)-N’-phenylurea (CPPU) or N-phenyl-N’-1,2,3-thiadiazol-5-ylurea (TDZ) in combination with α-naphthalene acetic acid (NAA). Somatic embryos appeared directly from explants after 4-6 weeks of culture; TDZ at 9.08 µM with 1.07 µM NAA was the best medium for somatic embryo induction from both leaf and petiole explants and subsequently embryo conversion. Based on this established regeneration method, an Agrobacterium-mediated transformation procedure was developed. Leaf discs and petiole segments were inoculated and co-cultivated with A. tumefaciens strain EHA105, carrying the binary vector pLC902 which contained the hygromycin phosphotransferase (HPT) selectable gene and the enhanced green fluorescent protein (EGFP) reporter gene. The leaf discs and petiole segments were cultured on MS medium supplemented with 9.08 µM TDZ and 1.07 µM NAA as well as cefotaxime, carbenicillin and hygromycin. Somatic embryos formed from leaf and petiole explants, and embryo conversion resulted in healthy plantlets. A total of 237 putative transgenic plants were obtained, and all of them expressed EGFP fluorescence throughout the entire plant, including roots. Results also showed that the co-cultivation period significantly affected transformation efficiency. Five-day co-cultivation led to100% of leaf explants showing transient EGFP fluorescence and 23.8% of leaf explants producing somatic embryos expressing stable EGFP fluorescence. Seven-day co-cultivation resulted in100% of petiole explants showing transient EGFP fluorescence and 14.3% of petiole explants producing somatic embryos expressing stable EGFP fluorescence.