Abstract: The full-length of intact Zea mays gene for phosphoenolpyruvate carboxylase gene (ZmC₄Ppc) is 6 781 bp. The products of PCR for this gene were not clear with poor repeatability, resulting in that it was difficult for marker-assisted selection (MAS) both in rice and maize. For selecting the markers for MAS, sequences presented only in maize rather than in rice were identified by BLAST, and used for primer design using Primer Premier 5.0. A pair of specific primer termed MRpc (Forward: 5’ AAGCAGGGAAGCGAGACG 3’, Reverse: 5’ GATTGCCGCCAGCAGTAG 3’) was used for selection of transformed rice, and ZmC₄Ppc could be highly and constitutively expressed at each tested developmental stages in the transformed rice selected by using MRpc. Thus, MRpc was used for MAS of progenies carrying ZmC₄Ppc gene in rice and some restorer lines with ZmC₄Ppc (e.g. FPM881) derived from ZmC₄Ppc-transformed Kitaake backcrossed with a restorer line Shuhui 881 were obtained. The analyses on genetic background, PEPCase activity, net photosynthetic rate, general combining ability (GCA) and specific combining ability (SCA) of FPM881 showed that similarity of genetic background reached above 95%, the PEPCase and net photosynthetic rate were higher than those of the control, and some of the progenies carrying ZmC₄Ppc gene had better GCA and SCA for grain yield per plant, number of panicles per plant, and 1000-grain weight than those of the control. This suggested that the introduction of maize ZmC₄Ppc gene via MAS and its stable expression could increase grain yield of rice and would likely provide a pathway for rice varietal improvement.

Key words: rice, Zea mays gene for phosphoenolpyruvate carboxylase, primer design, marker-assisted selection, varietal improvement, phosphoenolpyruvate carboxylase activity, net photosynthetic rate, general combining ability, special combniing ability