Figure 1
Schematic for substrate washing tank modified from original design of Robert Morrow, ORBITEC.
Figure 2
Custom substrate washer built at the Kennedy Space Center, FL.
Table 1
Percentages of germination and microbial contamination in preliminary lettuce seed tests of fuming surface sterilization methods. Tests were conducted with ‘Waldmann's Green’ lettuce seeds that had microbial contamination. Germination was tested immediately and following 1 month of storage for promising treatments.
| Fuming Treatment | Germination | Contamination | Stored Germination |
|---|---|---|---|
| Bleach alone-12 h | 96% | 100% | - |
| Bleach+1 mL HCL-20 h | 0% | 0% | - |
| Bleach+0.5 mL HCL-1h | 100% | 0% | 92% |
| Bleach+1 mL HCL-1h | 100% | 0% | 4% |
| Untreated | 96% – 100 % | 100% | 95% |
Figure 3
A. Schematic side view of a plant pillow. B. Schematic end cross sectional view of plant pillow. C. Schematic cut away side view of plant pillow showing seed placement. D. Photo of a planted pillow prepared for flight.
Table 2
Percentages of germination (G) and contamination (C) observed for Veggie candidate flight seeds tested with different surface sterilization treatments. Dashes indicate that these tests were not performed. Values in bold indicate methods selected for flight seeds.
| Treatment | ‘Profusion’ Zinnia | ‘Durango’ French Marigold | ‘Outredgeous’ Lettuce | ‘Tokyo Bekana’ Chinese cabbage | ||||
|---|---|---|---|---|---|---|---|---|
| G | C | G | C | G | C | G | C | |
| Bleach + 0.5 mL HCL - 1h | 80–100% | 0% | 70% | 40% | 100% | 0% | 100% | 0% |
| Bleach + 1 mL HCL - 1h | 80% | 0% | 70% | 60% | - | - | 100% | 0% |
| Bleach + 0.5 mL HCL - 5h | 30% | 0% | 10% | 0% | - | - | - | - |
| 70% EtOH – 5 min | 90–100% | 0% | 30% | 60% | 80–100% | 20–40% | 100% | 100% |
| 70% EtOH – 10 min | - | - | - | - | - | - | 92% | 20% |
| Untreated | 67–100% | 20–40% | 60–100% | 100% | 90–100% | 20–80% | 100% | 100% |
Table 3
Percentages of seeds germinating in the VEG-01 and VEG-03 tests. Each value represents a percentage of the 12 seeds planted in 6 pillows.