According to garden historian Paige Johnson: After WWII, there was a concerted effort to find 'peaceful' uses for atomic energy.
The experiments were mostly conducted in giant gamma gardens on the grounds of national laboratories in the US but also in Europe and countries of the [then-]USSR.
Mutation breeding is commonly used to produce traits in crops such as larger seeds, new colors, or sweeter fruits, that either cannot be found in nature or have been lost during evolution.
Radiation breeding was discovered in the 1920s when Lewis Stadler of the University of Missouri used X-rays on maize and barley.
[18] High rates of chromosome aberrations resulting from ionizing radiation and the accompanied detrimental effects made researchers look for alternate sources for inducing mutations.
Ethyl methanesulfonate (EMS) is the most popular because of its effectiveness and ease of handling, especially its detoxification through hydrolysis for disposal.
Nitroso compounds are the other alkylating agents widely used, but they are light-sensitive and more precautions need to be taken because of their higher volatility.
[citation needed] Interest in the use of bacterial restriction endonucleases (RE) – for example Fok1[2] and CRISPR/Cas9[1][2] – to study double-stranded breaks in plant DNA began in the mid-nineties.
These breaks in DNA, otherwise known as DSBs, were found to be the source of much chromosomal damage in eukaryotes, causing mutations in plant varieties.
Due to restriction endonucleases' ability to facilitate damage in chromosomes and DNA, REs have the capability of being used as a new method of mutagenesis to promote the proliferation of mutated plant varieties.
Other replications of space conditions include irradiation of seeds by a heavy 7 Li-ion beam or mixed high-energy particles.
Ion beams change DNA in a manner that makes it look vastly different than its original makeup, more so than when traditional irradiation techniques are used.
During the process of ion beam radiation, seeds are wedged between two kapton films and irradiated for roughly two minutes.
The broader mutation spectrum was revealed through the largely varied amount of flower phenotypes produced by ion beams.
Ion beam technology has been used in the discovery of new genes responsible for the creation of more robust plants, but its most prevalent use is commercially for producing new flower phenotypes, like striped chrysanthemums.
[25] While the abundance and variation of transgenic organisms in human food systems, and their effect on agricultural biodiversity, ecosystem health and human health is somewhat well documented, mutagenic plants and their role on human food systems is less well known, with one journalist writing "Though poorly known, radiation breeding has produced thousands of useful mutants and a sizable fraction of the world's crops...including varieties of rice, wheat, barley, pears, peas, cotton, peppermint, sunflowers, peanuts, grapefruit, sesame, bananas, cassava and sorghum.
[26][27][28][29] Mutagenic varieties tend to be made freely available for plant breeding, in contrast to many commercial plant varieties or germplasm that increasingly have restrictions on their use[6]: 187 such as terms of use, patents and proposed genetic user restriction technologies and other intellectual property regimes and modes of enforcement.