Molecular Breeding

, Volume 4, Issue 2, pp 111–117

Analysis of mannose selection used for transformation of sugar beet


  • Morten Joersbo
    • Danisco Biotechnology
  • Iain Donaldson
    • Danisco Biotechnology
  • Jette Kreiberg
    • Danisco Biotechnology
  • Steen Guldager Petersen
    • Danisco Biotechnology
  • Janne Brunstedt
    • Danisco Biotechnology
  • Finn T. Okkels
    • DLF-Trifolium A/S, Højerupvej 31

DOI: 10.1023/A:1009633809610

Cite this article as:
Joersbo, M., Donaldson, I., Kreiberg, J. et al. Molecular Breeding (1998) 4: 111. doi:10.1023/A:1009633809610


Various factors affecting mannose selection for the production of transgenic plants were studied using Agrobacterium tumefaciens-mediated transformation of sugar beet (Beta vulgaris L.) cotyledonary explants. The selection system is based on the Escherichia coli phosphomannose isomerase (PMI) gene as selectable gene and mannose as selective agent. Transformation frequencies were about 10-fold higher than for kanamycin selection but were only obtained at low selection pressures (1.0–1.5 g/l mannose) where 20–30% of the explants produced shoots. The non-transgenic shoots were eliminated during the selection procedure by a stepwise increase in the mannose concentration up to 10 g/l. Analysis of the transformed shoots showed that the PMI activity varied from 2.4 mU/mg to 350 mU/mg but the expression level was independent of the selection pressure. Complete resistance to mannose of transformed shoots was observed already at low PMI activities (7.5 mU/mg). Genomic DNA blot analysis confirmed the presence of the PMI gene in all transformants analysed. The possible mode of action of mannose selection compared to other selection methods is discussed.

Beta vulgarismannose selectionphosphomannose isomerasetransformation

Copyright information

© Kluwer Academic Publishers 1998