One of the most important milestones in spaceflight exploration will surely be the creation of the first fully bioregenerative life support system: a habitat that can fully sustain humans with proper gas exchange, plant growth and cultivation, water cycling, etc. Depending on how you look at it, biodomes can be a model for bioregenerative life support systems or the end goal product.
The preferred term for a spaceflight focused biodome is a “controlled ecological life support system.” Various organizations have their own experimental biodomes: the Mars Desert Research Station, Biosphere 2, or Yuegong-1.
Plant growth is always critical in biodomes. In the context of astrobotany, biodomes should support crops that are optimized for spaceflight.