Transformation technology as a research or breeding tool to improve maize is routinely used in most industrial and some specialized public laboratories. However, transformation of many inbred lines remains a challenging task, especially when using
Agrobacterium tumefaciens as the delivery method. Here we report success in generating transgenic plants and progeny from three maize inbred lines using an
Agrobacterium-mediated standard binary vector system to target maize immature embryos. Eleven maize inbred lines were pre-screened for transformation frequency using N6 salts. A subset of three maize inbred lines was then systematically evaluated for frequency of post-infection embryogenic callus induction and transformation on four media regimes: N6 or MS salts in each of two distinct media backgrounds. Transgenic plants recovered from inbred lines B104, B114, and Ky21 were analyzed for transgene integration, expression, and transmission. Average transformation frequencies of 6.4% (for B104), 2.8% (for B114), and 8% (for Ky21) were achieved using MS salts. Availability of
Agrobacterium-mediated maize inbred line transformation will improve future opportunities for maize genetic and functional genomic studies.
Keywords
Agrobacterium tumefaciens
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Zea mays
- Inbred maize - MS salts - N6 salts - Type I callus
Communicated by J. C. Register