Life Cycles of Higher Plants Under Microgravity Conditions (SpaceSeed) - 08.20.14
ISS Science for Everyone
Science Objectives for Everyone
Life Cycles of Higher Plants Under Microgravity Conditions (SpaceSeed) cultivates Arabidopsis thaliana (a small flowering plant) in microgravity to improve the productivity of crops in space as well as for understanding the role of gravity in regulating the life cycle of higher plants.
Science Results for Everyone
Eating and breathing. These are both important in space, and plants can help with both. The Space Seed experiment grows plants in microgravity to find out the role gravity plays in regulating the seed-to-seed life cycle. Results show seeds grow and develope leaves, flowers, and fruit regardless of the amount of gravity. Leaves under microgravity remained dark green longer, though, indicating that microgravity delays leaf aging. One gene involved in supporting flower stalks is suppressed, while four other genes are enhanced. This indicates that microgravity changes the way some genes behave in cell growth in plants.
Sponsoring Space Agency
Japan Aerospace Exploration Agency (JAXA)
ISS Expedition Duration
March 2009 - March 2010
Previous ISS Missions
SpaceSeed first began operations on ISS Increment 19/20.
- Since gravity strongly influences developmental processes throughout the life cycle of higher plants on Earth, this research is undertaken to cultivate Arabidopsis thaliana on the JEM, whereby the life cycle is relatively short.
- The controlling mechanism of developmental processes in Arabidopsis has been physiologically and genetically studied with various mutants and transgenic plants on Earth. The experiments with Arabidopsis under the microgravity environment on JEM will provide an abundance of important and useful information necessary for improving the productivity of crops in space, as well as for understanding the role of gravity in regulating the life cycle of higher plants.
Downlinked images from the Kibo laboratory demonstrated that seeds started to germinate 3 days after initial watering, followed by the development of rosette leaves, flower stalks, flowers and siliques. Fruit formation was also observed regardless of the magnitude of gravity. The rosette leaves under microgravity remained dark green for longer as compared to plants grown in the 1G centrifuge, indicating that leaf senescence is delayed under microgravity. Microarray analysis of genes involved in supporting flower stalks revealed that under microgravity conditions, one gene was downregulated, while four genes were upregulated, indicating that microgravity conditions modify the pattern of gene expression involved in secondary cell formation.
Ground Based Results Publications
Yano S, Kasahara H, Masuda D, Tanigaki F, Shimazu T, Suzuki H, Karahara I, Soga K, Hoson T, Tayama I, Tsuchiya Y, Kamisaka S. Improvements in and actual performance of the Plant Experiment Unit onboard Kibo, the Japanese Experiment Module on the International Space Station. Advances in Space Research. 2012.
NASA Image: ISS021-E-006267 NASA astronaut Nicole Stott, Expedition 21 flight engineer, works with the Cell Biology Experiment Facility (CBEF) SPACE SEED experiment in the Kibo laboratory of the International Space Station.
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NASA Image: ISS021-E-006274 A close-up view of the Cell Biology Experiment Facility (CBEF) SPACE SEED experiment is featured in this image photographed by an Expedition 21 crew member in the Kibo laboratory on the International Space Station.
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NASA Image: ISS027E008229 - NASA astronaut Cady Coleman and European Space Agency astronaut Paolo Nespoli, both Expedition 27 flight engineers, are pictured near a bag of space seeds floating freely in the Kibo laboratory of the International Space Station.
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