You might not have heard of it, but you’ve probably eaten a fruit or vegetable that’s been created through radiation breeding. This technique exposes seeds to radiation in order to create mutations in the plant’s DNA. Often, the mutated plants are useless. But occasionally, the genetic mutations give the plants useful new properties, like resistance to drought or disease, or higher yields.
Radiation breeding was first used in the 1920s, when X-rays were used to alter the properties of maize and barley. Today, it is carried out by firing beams of electrons, neutrons or charged particles (ions) at the seeds, or exposing them to radioactive sources like cobalt-60.
The Mutant Variety Database, which collects information on plant varieties created through radiation breeding and other similar ‘mutation breeding’ techniques, logs over 3,000 improved varieties, including grapefruit, rice, wheat and barley. In Vietnam, around half the soya beans planted are mutant varieties.
Radiation breeding is different from genetic modification in that it only alters existing DNA – no new genetic material is introduced. The crops themselves are not radioactive, and given that billions of people have eaten them with no ill effects, it’s unlikely they’re harmful.
Radiation breeding technology is also relatively cheap, so as the climate warms, the technique might provide a way for developing countries with limited resources to create drought-resistant crops.