This will lead to the production of recombinase enzyme, which will excise the blocking sequence or the spacer which blocked the expression of the terminator gene (e.g. RIP).

Due to excision of the blocking sequence, the promoter will come to lie adjacent to the terminator gene, which will now be expressed and will kill the developing embryos. In actual commercial production and sale of seeds of pure lines as above, the crop for commercial seed production will be grown by the breeder or seed company without chemical treatment.

The harvested seeds from this crop, will be treated with the chemical, before it is sold to the fanner, so that in crops grown by the farmer, the toxic substance is produced at the time of embryo development, and the embryos die or fail to develop.

Genetic Basis of Terminator Technology