Plant biology in reduced gravity on the Moon and Mars
Article first published online: 25 JUL 2013
© 2013 German Botanical Society and The Royal Botanical Society of the Netherlands
Special Issue: Plant Biology in Space. Guest Editors: V. Legué & K. Palme. The German Botanical Society, the Royal Botanical Society of the Netherlands and Wiley have published this supplement without financial support.
Volume 16, Issue Supplement s1, pages 12–17, January 2014
How to Cite
Kiss, J. Z. (2014), Plant biology in reduced gravity on the Moon and Mars. Plant Biology, 16: 12–17. doi: 10.1111/plb.12031
- Issue published online: 23 DEC 2013
- Article first published online: 25 JUL 2013
- Manuscript Accepted: 28 FEB 2013
- Manuscript Received: 4 JAN 2013
- NASA. Grant Numbers: NNX10AM86G, NNX12AO65G
- Fractional gravity;
- International Space Station;
- reduced gravity;
While there have been numerous studies on the effects of microgravity on plant biology since the beginning of the Space Age, our knowledge of the effects of reduced gravity (less than the Earth nominal 1 g) on plant physiology and development is very limited. Since international space agencies have cited manned exploration of Moon/Mars as long-term goals, it is important to understand plant biology at the lunar (0.17 g) and Martian levels of gravity (0.38 g), as plants are likely to be part of bioregenerative life-support systems on these missions. First, the methods to obtain microgravity and reduced gravity such as drop towers, parabolic flights, sounding rockets and orbiting spacecraft are reviewed. Studies on gravitaxis and gravitropism in algae have suggested that the threshold level of gravity sensing is around 0.3 g or less. Recent experiments on the International Space Station (ISS) showed attenuation of phototropism in higher plants occurs at levels ranging from 0.l g to 0.3 g. Taken together, these studies suggest that the reduced gravity level on Mars of 0.38 g may be enough so that the gravity level per se would not be a major problem for plant development. Studies that have directly considered the impact of reduced gravity and microgravity on bioregenerative life-support systems have identified important biophysical changes in the reduced gravity environments that impact the design of these systems. The author suggests that the current ISS laboratory facilities with on-board centrifuges should be used as a test bed in which to explore the effects of reduced gravity on plant biology, including those factors that are directly related to developing life-support systems necessary for Moon and Mars exploration.