Did you know that the peppermint flavor in your chewing gum and toothpaste, and the red-ruby grapefruit on your plate, is the result of mutation caused by deliberate irradiation? Apparently, after World War II, there was a concerted effort to find peaceful uses for atomic energy. One of the ideas was to bombard plants with radiation and produce lots of mutations, some of which, it was hoped, would lead to plants that were disease or cold-resistant or just had unusual colors. The experiments were mostly conducted in giant gamma gardens on the grounds of national laboratories in the US, Europe and countries of the former USSR, leading to untold numbers of new plant varieties. The disease resistant peppermint plant and the 'Rio Star' grapefruit, which accounts for 75% of the grapefruit production in Texas, were created in these atomic gardens.
Modern genetic engineering has replaced the need for atomic gardening, but the legacy is still carried forward by the Institute of Radiation Breeding in Japan, which currently owns the largest, and possibly the only surviving gamma garden in the world, at Hitachiōmiya in Ibaraki Prefecture. The circular garden measures 100 meters in radius, and enclosed by an 8-meter high shielding dike wall. Species within are irradiated with gamma rays from a cobalt-60 source placed inside a central pole. The purpose here is to generate new traits such as tolerance to fungus infection or consumer-friendlier fruit colors, and in general, help meet demands for development of crop varieties with new traits.
Nanotechnologist Paige Johnson
Nanotechnologist Paige Johnson of the University of Tulsa, Oklahoma, who researches atomic garden history in her spare time, says: "If you think of genetic modification today as slicing the genome with a scalpel, in the 1960s they were hitting it with a hammer". Indeed, before scientist learned how to modify genes, they induced mutations with radiation and hoped for the best.