The DNA of the transgenic
plants and un-transformed plant was digested with EcoRI, which
has a unique cleavage site in the T-DNA region in the vector and
hybridized with the OCI gene probe. The resistant, middle resistant
and susceptible transgenic plants displayed different integration
patterns and the copy number of integrated OCI gene varied from
1 to 3, but there was no clear relationship between stem nematode
resistance and copy number of integrated OCI gene (Fig. 3)