Biologia Plantarum

, 52:215 | Cite as

Generation of low copy number and stably expressing transgenic creeping bentgrass plants using minimal gene cassette bombardment

  • J. Jayaraj
  • G. H. Liang
  • S. Muthukrishnan
  • Z. K. Punja
Original Papers


A minimal gene cassette comprised of the ubiquitin (Ubi) promoter + green fluorescent protein (Gfp) gene + Nos terminator DNA sequences, derived from the plasmid vector pPZP201-Gfp was utilized for transformation of creeping bentgrass using particle bombardment. Bentgrass calli bombarded individually with equivalent amounts of the cassette or whole plasmid DNA were compared for Gfp expression and the GFP-positive calli were subsequently regenerated into plants. Percentage of GFP expressing calli and the number of GFP spots/calli were significantly higher in calli that were bombarded with the minimal gene cassette when compared to the whole plasmid. The Gfp expression was stable up to the T2 generation in minimal gene cassette transformants and there was a lower degree of gene silencing. Southern blot analysis of transgenic plants derived from minimum gene cassette bombardment revealed the presence of single or few copy of the transgene and fairly simple integration patterns. In comparison, whole plasmid transformants had multiple copies and complex integration patterns of the transgene. These results illustrate the advantages of using simple gene cassette for stable plant transformation in bentgrass with possible applications to other plant species.

Additional key words

gene integration green fluorescent protein expression plant transformation 



calli induction medium


2,4-dichlorophenoxyacetic acid


green fluorescent protein


whole plasmid


minimum gene cassette


Murashige and Skoog’s medium


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Copyright information

© Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Praha 2008

Authors and Affiliations

  • J. Jayaraj
    • 1
  • G. H. Liang
    • 2
  • S. Muthukrishnan
    • 3
  • Z. K. Punja
    • 1
  1. 1.Department of Biological SciencesSimon Fraser UniversityBurnabyCanada
  2. 2.Department of AgronomyKansas State UniversityManhattanUSA
  3. 3.Department of BiochemistryKansas State UniversityManhattanUSA

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