[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 pCAM-BIA3301 .The expression cassette was inserted into the transitional vector pCAMBIA 1301-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 Agrobacte-rium tumefaciens-mediated method .The regeneration plants were detected by molecular biology tech-niques .[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 gen-eration 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 T 2 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 founda-tion for creation of new corn germplasm with high phosphorus efficiency and high maize yield .%[目的]构建植酸酶基因（ phyA）根部特异表达的重组植物表达载体，并利用其创制磷高效利用的玉米新种质．[方法]通过PCR方法从携带phyA的表达载体pCAMBIA3301中扩增出phyA表达元件ZmGLU1P-phyA-Nos，并将其插入到带有耐盐基因的中间载体pCAMBIA1301-BADH 上，获得phyA根特异表达的植物表达载体：pCAM-BIA1301-ZmGLU1P-phyA-Nos，通过农杆菌介导法转化玉米胚性愈伤组织，并对再生植株进行分子生物学检测分析．[结果和结论]经PCR检测获得了9株T0代阳性植株；T1代植株的抗盐筛选、PCR检测、Southern杂交检测及RT-PCR检测证明了phyA已经整合到玉米基因组中，获得6株T1代阳性植株；T2代植株的RT-PCR及根组织的酶活性测定结果表明，phyA在转基因植株根部大量表达，植酸酶活性平均比对照植株提高了10.9倍，活性最高的达到5.432 U/g．植酸酶基因在转基因植株根部大量特异表达，获得了转phyA的玉米新种质，为创制磷高效利用的玉米新种质、提高玉米的产量奠定了基础．
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