According to NASA, five major hazards appear during long spaceflights: space radiation, isolation and confinement, distance from Earth, low gravity, and the hostile and closed environment of a spacecraft. Living plants and freshly grown food could play a major role in supporting three of these: nutrition, medical needs and crew psychology.
Genes involved in plants’ stress responses have been identified but to reduce or mitigate those effects scientists need to modify the expression of existing genes or add space-adaptation genes into the genomes. This can be achieved using gene editing and some candidate genes have already been specifically identified and studied. For example, ARG1 (Altered Response to Gravity 1), a gene known to affect gravity responses in plants on Earth, is involved in the expression of 127 genes related to spaceflight adaptation.
…
Other genes, called space-adaptation genes, such as genes related to radiation, perchlorate, dwarfism and cold temperature, are potentially worth studying as they would help plants resist the harsh conditions of space. For example, microorganisms adapted to hypersaline environments possess genes for UV resistance and perchlorate resistance. Many dwarf varieties (e.g. of wheat) have already been cultivated on the ISS and the dwarf cherry tomato ‘Red Robin’ might be grown in the ISS as part of NASA’s Veg-05 experiment.