Cucumber transformation methods - the review

Cucumber transformation methods - the review Summary Several aspects of cucumber transformation including the ways of trans- gene introduction, factors influencing the transformation efficiency and the fate of the introduced genes were reviewed. Various transgenes have been intro- duced into the cucumber genome mostly via the Agrobacterium-mediated trans- formation. The frequency of Agrobacterium-mediated transformation ranged from 0.8 to 10% and was influenced by the selection agent, the regeneration effi- ciency, activation of vir genes expression, the explant size, bacteria cell density, the length of exposure and the co-cultivation period. The transgenes were inte- grated mostly as single copy in the Agrobacterium-mediated transformation and as multiple copies in direct transformation. Variable levels of the transgene ex- pression were observed. The transmission of the transgenes as well as the transgenic phenotype follow the Mendelian, and rarely non-Mendelian, ratio. The production of marker-free transgenic cucumber and use of an alternative transformation method are recommended.