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.
Read more about this topic: Genetically Modified Crops
Famous quotes containing the words flow and/or plants:
“But even suppose blood should flow. Is there not a sort of blood shed when the conscience is wounded? Through this wound a man’s real manhood and immortality flow out, and he bleeds to an everlasting death. I see this blood flowing now.”
—Henry David Thoreau (1817–1862)
“... feminism is a political term and it must be recognized as such: it is political in women’s terms. What are these terms? Essentially it means making connections: between personal power and economic power, between domestic oppression and labor exploitation, between plants and chemicals, feelings and theories; it means making connections between our inside worlds and the outside world.”
—Anica Vesel Mander, U.S. author and feminist, and Anne Kent Rush (b. 1945)