was activated on February 12, 2002. The growth chamber contains Arabadopsis
seeds produced during ADVASC's first flight (ADVASC-GC-01). "This will
be second-generation Arabadopsis plants produced from the seeds produced
by those first-generation space-grown plants," described Dr. Weijia
Zhou, principal investigator for ADVASC and director of the Wisconsin Center
for Space Automation and Robotics (WCSAR) at the University of Wisconsin,
Madison. "Additionally, we are going to sample the plant tissue and
preserve it for RNA and DNA analysis after returning to the ground. Hopefully
it will provide important information regarding the impact of low gravity
on the plant gene expression."
ADVASC-GC-01, activated on May 10, 2001, was the first experiment on Station to return data to ground centers via video. By the week of May 28, the seeds had sprouted. The research team reported that the seedlings appeared on the video to be slightly larger than expected. The plants began to flower during the week of June 11 and had produced seeds within two weeks. During the first week of July, Increment 2 Flight Engineer Jim Voss had raised the heat and removed nutrients, fluids, and gases from ADVASC unit in order to dry out the plants and preserve them for their return to Earth.
The unit, plants, and samples were returned to Earth by STS-104 on July 24, and sent to WCSAR. Approximately 90 percent of the seeds sent into space germinated. Of those, about 70 percent grew siliques (elongated, two-sided seed capsules characteristic of the mustard family), with an average of 24 siliques containing 36 seeds per plant. WCSAR researchers are also comparing the space-grown plants to a control group grown under similar conditions on the ground. Part of the analysis also includes determining cell wall and chemical composition. Differences between the ADVASC plants and the ground-control plants will likely be due to the microgravity environment. The overall health and vigor of the space-grown plants will tell researchers whether the growing conditions—temperature, moisture, and fertilizer concentrations—were optimal. Some of the seeds are currently being grown in ADVASC-GC-02, but most of the seeds were turned over to Space Explorers, Inc., for use in their educational kits and other commercial endeavors.
Only two other space-based plant-growth experiments have yielded a whole life cycle. An earlier, long-duration experiment on Mir using wheat yielded a complete life cycle, but produced only empty seed heads (due to a significantly elevated ambient ethylene concentration). The brassica rapa plant experiment successfully produced multigeneration seeds on Mir.Applications
Long-term plant research may allow crews on long-duration space flights to successfully grow and nourish their own crops in space. Plants also provide a natural air and water filtration system. From the humble beginnings represented by ADVASC may come advanced, large-scale plant growth systems for spacecraft. Space horticulture is the cornerstone of a healthy, enclosed life support system for future human space exploration. Furthermore, plant growth systems provide a little piece of Earth that helps make the spacecraft environment feel more like home.
Finding the key to growing crops in space— - a challenging growing environment—may also improve crop yields on Earth by helping scientists to genetically tailor plants that will withstand disease and inhospitable conditions, and will require less growing space.
Researchers have also found that the light used for photosynthesis in ADVASC heals wounds and improves the effectiveness of cancer-fighting drugs. The light-emitting diodes developed for WCSAR by Quantum Devices, Inc., have been successfully used in surgical devices that remove tumors.
Additionally, ADVASC provides an active link between science conducted onboard the ISS and the education community. Space Explorers, Inc., commercial partner on the ADVASC experiment, has developed Orbital Laboratory, an Internet-based, multimedia educational tool that allows students (grades K-12) to conduct experiments on the ISS and to analyze returned data. Students will be able to access ADVASC plant data and discuss data gathered by other participating schools worldwide. Space Explorers, Inc., and InnerLink, Inc., have developed the Orbital Laboratory Payload 002 Innerlinkit, a commercially available kit that contains supplies necessary to participate in the ADVASC experiment and a one-year subscription to the Orbital Laboratory Web site.Related Publications
D.M. Porterfield, D.J. Barta, D.W. Ming, R.C. Morrow, and M.E. Musgrave. 2000. ASTROCULTURE (TM) root metabolism and cytochemical analysis. Adv Space Res. 26(2): 315-318.
R.J. Bula and W. Zhou . 2000. First flight of the ASTROCULTURE (TM) experiment as a part of the U.S. Shuttle/MIR program. Adv Space Res. 26(2): 247-252.
Current Space Flight Missions (WCSAR)
ISS Increment 2, 6A to 7A (WCSAR)
NASA Life Sciences Research Highlights: Researchers achieve breakthrough by growing plants from seed-to-seed in space (Spaceline; PDF file)
WCSAR reaps first crop of seeds from International Space Station (University of Wisconsin-Madison College of Engineering)