Development of corn new germplasm with transgenic phyA

【Objective】To construct the vector of phytase gene(phyA) specific expression in roots and to develop transgenic maize with high phosphorus efficiency.【Method】 Using PCR method, the expression cassette ZmGLU1P-phyA-Nos was constructed by amplifying phyA from its expression vector pCAMBIA3301. The expression cassette was inserted into the transitional vector pCAMBIA1301-BADH with salt-tolerance BADH gene, which formed pCAMBIA1301-ZmGLU1P-phyA-Nos，the expression vector of phyA specific expression in roots. The phyA was transformed into maize embryogenic callus via Agrobacterium tumefaciens-mediated method. The regeneration plants were detected by molecular biology techniques. 【Result and conclusion】 The transformed plants were detected by PCR and 9 transgenic lines were obtained. Through salt-resistant selection, PCR, Southern blotting and RT-PCR analysis of T₁ generation plants, the results showed that phyA were successfully integrated into the maize genome and 6 transgenic lines were obtained.The analysis of phytase activity in maize plant root of T₂ generation plants showed that the phytase was able to be expressed highly and secreted from roots. The phytase activity of transformed plants increased 10.9 times on average, with the highest phytase activity being 5.432U/g. The new corn germplasm with transgenic phytase was obtained. Moreover, this study could lay a foundation for creation of new corn germplasm with high phosphorus efficiency and high maize yield.