Genetically Modified Crops - Gene Flow in Plants

Gene Flow in Plants

Scientists first discovered that DNA naturally transfers between organisms in 1946. It is now known that there are several natural mechanisms for flow of genes, or (horizontal gene transfer), and that these occur in nature on a large scale - for example, it is a major mechanism for antibiotic resistance in pathogenic bacteria, and it occurs between plant species. This is facilitated by transposons, retrotransposons, proviruses and other mobile genetic elements that naturally translocate to new sites in a genome. They often move to new species over an evolutionary time scale and play a major role in dynamic changes to chromosomes during evolution.

The introduction of foreign germplasm into crops has been achieved by traditional crop breeders by artificially overcoming fertility barriers. A hybrid cereal was created in 1875, by crossing wheat and rye. Since then important traits have been introduced into wheat, including dwarfing genes and rust resistance. Plant tissue culture and the induction of mutations have also enabled humans to artificially alter the makeup of plant genomes.