Abstract: Construction of expression vector is the basis of gene transformation, and a high frequency of callus induction and regeneration is crucial for successfully obtaining transplant. In the present study, a highly efficient expression vector (pFUPaPb) that harbors the fused fragment of Pina ＆Pinb flanked with regulation sequences of Ω and poly(A) was constructed, employing ubiqutin as a promoter and bar gene as a selective marker. Common wheat variety Jing 411 is the donor of Pina and Pinb genes. pFUPaPb was transferred into durum wheat by biolistic method. After screening with bialophos and PCR amplification with gene specific primers, 35 transplants were obtained, and the expression of fused genes was detected in 2 of 16 transplants examined. Results indicated that SD2 is the comparatively efficient medium for callus induction of durum immature embryo, and MS+8 mg.L-1 zeatin is good for callus regeneration. The results provide a high expression vector for wheat grain harness modification, and useful information for understanding the functions of Pina and Pinb genes.

Key words: Pina ＆Pinb fused expression vector, durum wheat, immature embryo culture, transformation