Abstract:

【Objective】 Isolated from the cDNA library of millet immature seed, the gene pf40 (or its homolog ) is ubiquitously distributed in cereal’s crop genome. Preliminary studies indicate that the gene pf40 plays a role in promoting tillering (branching). This study aimed to clarify whether the function of gene pf40 (or its homolog) is related to the tillering in maize. 【Method】 Two plant expression vectors with sense and knock-out (RNAi) gene pf40 promoted by 35S promoter were introduced into the embryogenic callus of maize hybrids(Z3, Z31, Q31) through particle bombardment. Regenerated plants were verified to be transgenic by PCR amplification, Southern blot and tRNA dot blot. The observation about the phenotype of the tillers on the base of the transgenic plants stems could determine the effect of the gene pf40 on the tillers. 【Result】 After the hygromycin B selection and PCR screening, 53 transgenic plants were obtained. According to the results of PCR test, Southern blot and tRNA dot blot on T1 and T2 generation, the foreign gene pf40 had been integrated into the maize genome, also it could express and pass generation to generation. After investigated into the phenotypes of both the tiller nodes on the base of stems, unfortunately, no distinct difference was observed between the transgenic plants and the untransgenic plants. 【Conclusion】 The phenotype of the maize without tillers will not be changed by merely altering the expression of the gene pf40 or its homolog. And the exact functions of the gene pf40 or its homolog in maize need further to be investigated.

Key words: pf40')">pf40, maize, transgenic plants, tillering (branching)