Search NASA⌕ Search

SEARCH · Search NASA

Results for “Space Crop Production”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12

Robotics in a controlled, ecological life support system

Controlled, Ecological Life Support Systems (CELSS) that utilize plants to provide food, water and oxygen could consume considerable amounts of labor unless crop production, recovery and processing are automated. Robotic manipulators equipped with special end-effectors and programmed to perform the sensing and materials handling tasks would minimize the amount of astronaut labor required. The Human Rated Test Facility (HRTF) planned for Johnson Space Center could discover and demonstrate techniques of crop production which can be reliably integrated with machinery to minimize labor requirements. Before the physical components (shelves, lighting fixtures, etc.) can be selected, a systems analysis must be performed to determine which alternative processes should be followed and how the materials handling tasks should be automated. Given that the current procedures used to grow crops in a CELSS may not be the best methods to automate, then what are the alternatives? How may plants be grown, harvested, processed for food, and the inedible components recycled? What commercial technologies current exist? What research efforts are underway to develop new technologies which might satisfy the need for automation in a CELSS? The answers to these questions should prove enlightening and provide some of the information necessary to perform the systems analysis. The planting, culturing, gathering, threshing and separation, food processing, and recovery of inedible portions of wheat were studied. The basic biological and materials handling processes of each task are defined and discussed. Current practices at Johnson Space Center and other NASA centers are described and compared to common production practices in the plant production industry. Technologies currently being researched which might be applicable are identified and illustrated. Finally, based on this knowledge, several scenarios are proposed for automating the tasks for wheat.

Miles, Gaines E.↗

Demonstration of in-Situ Resource Utilization of Lunar Regolith for Plant Growing Systems Through Scaled Capillary Models

The development of reliable and bioregenerative crop growth production systems is vital for human exploration into deep space. As the National Aeronautics and Space Administration (NASA) prepares for the Artemis missions, scientists need to find a way to provide consistent and sufficient water delivery for all stages of a plant’s life cycle. NASA has been able to successfully model passive flow through felt material, to mimic the water uptake and transport through a plant, in microgravity. However, more studies need to be conducted to adapt the model for a substrate-based system and incorporate how flow will change during each stage of plant growth. For future missions, payload requirements to support crop production systems will need to be limited, leading to the use of available resources, such as lunar regolith. Although numerous lunar regolith simulants are commercially available, few have been evaluated for their suitability in agricultural applications. First, a base regolith simulant will need to be identified based on its physical and chemical properties. Then, additional amendments to improve the properties of the simulants to support plant growth will be identified. The design and composition of the substrate will be based on water transport requirements for different stages of plant growth. Scaled capillary models can be utilized to study surface-tension driven flows through various designer substrates to modify the physical properties of the selected regolith simulant. These models can accurately represent how flow will act in a reduced gravity environment, which can be used to design a full-scale facility for surface missions. This project will aid space researchers in the design of future crop production systems for surface missions by creating a refined model that can be used at all stages of plant growth and utilize in situ resources.

Fluids↗

Plant Productivity and Characterization of Zeoponic Substrates after Three Successive Crops of Radish (Raphanus sativus L.)

The National Aeronautics and Space Administration (NASA) has developed a zeolite-based synthetic substrate, termed zeoponics. The zeoponic substrate (consisting of NH4(-) and K-exchanged clinoptilolite, synthetic apatite, and dolomite) provides all of the plant-essential nutrients through mineral dissolution and ion exchange, with only the addition of water. Previous studies have shown high productivity of wheat in zeoponic substrates; however, no experiments have been conducted on other crops. The objective of this study was to determine the productivity and nutrient uptake of radish (Raphanus sativus L.) grown in zeoponic substrates with three successive crops in the same substrate. Radish was chosen because of its sensitivities to NH4(+). Average fresh weights of edible roots were similar for radish grown in zeoponic substrates watered with deionized H2O (10.97 g/plant) and in potting mix control substrate irrigated with nutrient solution (10.92 g/plant). Average fresh weight production of edible roots for radish grown in same zeoponic substrate increased in yield over time with the lowest yield in the first crop (7.10 g/plant) and highest in the third crop (13.90 g/plant). The Ca plant tissue levels in radishes (1.8-2.9 wt. %) grown in zeoponic substrates are lower than the suggested sufficient range of 3.0-4.5 wt. % Ca; however, the Ca level is highest (2.9 wt. %) in radishes grown in the third crop in the same zeoponic substrates. The higher radish yield in the third crop was attributed to a reduction in an NH4(-) induced Ca deficiency that has been previously described for wheat grown in zeoponic substrates. The P levels in plant tissues of radish grown in the zeoponic substrates ranged from 0.94-1.15 wt. %; which is slightly higher than the sufficient levels of 0.3-0.7 wt. %. With the exception of Ca and P, other macronutrient and micronutrient levels in radish grown in zeoponic substrates were well within the recommended sufficient ranges. After three successive crops of radish growth, the zeoponic substrates had 52% of the original NH4(-)N and 78% of the original K remaining on zeolite exchange sites. Zeoponic substrates are capable of long-term productivity of radishes for space.

Gruener, J. E.↗

Nutrition of Antarctic-grown Crops to Supplement the Crew Diet, with Applications for Spaceflight

The availability of fresh produce during longer-duration spaceflight missions is being explored as a countermeasure for human biobehavioral health and performance, including how fresh fruits and vegetables can supplement the crew diet with nutrients that are predicted to become deficient throughout the missions. Crop production in the Veggie and Advanced Plant Habitat vegetable production chambers on the International Space Station (ISS) have tested pick-and-eat crops in spaceflight. However, the limited plant cultivation volume of these chambers has restricted the sample sizes and biomass allocated for nutrition assessment. To gain a better understanding of the nutrient composition of pick-and-eat crops, leafy greens and fruiting plants were grown in the EDEN ISS plant cultivation facility near the German Neumayer Station III in Antarctica from March 2021 to January 2022. Target crops for nutrition sampling aligned with cultivars grown in spaceflight, including ‘Outredgeous’ red romaine lettuce, Mizuna mustard, ‘Red Robin’ dwarf cherry tomato, and NuMex ‘Española Improved’ chili pepper. Plants subsamples were taken at harvest; in the event of multiple harvests from the same plants, subsamples were taken at both the first and final harvests. ‘Outredgeous’ and Mizuna were also grown multiple times throughout the year, allowing multiple grow-outs to be analyzed for potential effects across the growing season. Subsamples were first weighed for fresh mass, dried in a dedicated oven at 70°C for 96 h, weighed again, and stored in air-tight containers inside Neumayer Station III. At the beginning of 2022, the samples were shipped to NASA’s Kennedy Space Center, where they are currently being analyzed with ion chromatography for nutrients of interest in the astronaut diet, including calcium, iron, magnesium, and potassium. This study aims to increase our understanding of how the crops that have successfully grown on the ISS can supplement the crew diet, as well as how other factors like plant age and the number of days the facility has been in operation may impact nutrient concentrations. Such findings can improve the crop selection process and how pick-and-eat crops are cultivated during spaceflight missions.

Jess M. Bunchek↗

Nutrition of Antarctic-grown Crops to Supplement the Crew Diet, with Applications for Spaceflight

The availability of fresh produce during longer-duration spaceflight missions is being explored as a countermeasure for human biobehavioral health and performance, including how fresh fruits and vegetables can supplement the crew diet with nutrients that are predicted to become deficient throughout the missions. Crop production in the Veggie and Advanced Plant Habitat vegetable production chambers on the International Space Station (ISS) have tested pick-and-eat crops in spaceflight. However, the limited plant cultivation volume of these chambers has restricted the sample sizes and biomass allocated for nutrition assessment. To gain a better understanding of the nutrient composition of pick-and-eat crops, leafy greens and fruiting plants were grown in the EDEN ISS plant cultivation facility near the German Neumayer Station III in Antarctica from March 2021 to January 2022. Target crops for nutrition sampling aligned with cultivars grown in spaceflight, including ‘Outredgeous’ red romaine lettuce, Mizuna mustard, ‘Red Robin’ dwarf cherry tomato, and NuMex ‘Española Improved’ chili pepper. Plants subsamples were taken at harvest; in the event of multiple harvests from the same plants, subsamples were taken at both the first and final harvests. ‘Outredgeous’ and Mizuna were also grown multiple times throughout the year, allowing multiple grow-outs to be analyzed for potential effects across the growing season. Subsamples were first weighed for fresh mass, dried in a dedicated oven at 70°C for 96 h, weighed again, and stored in air-tight containers inside Neumayer Station III. At the beginning of 2022, the samples were shipped to NASA’s Kennedy Space Center, where they are currently being analyzed with ion chromatography for nutrients of interest in the astronaut diet, including calcium, iron, magnesium, and potassium. This study aims to increase our understanding of how the crops that have successfully grown on the ISS can supplement the crew diet, as well as how other factors like plant age and the number of days the facility has been in operation may impact nutrient concentrations. Such findings can improve the crop selection process and how pick-and-eat crops are cultivated during spaceflight missions.

Jess M. Bunchek↗

Preliminary test results from the CELSS Test Facility Engineering Development Unit

As part of the NASA Controlled Ecological Life Support System (CELSS) Program, a CELSS Test Facility (CTF) is being planned for installation on the Space Station. The CTF will be used to provide data on the productivity and efficiency of a variety of CELSS higher plant crops grown in the microgravity environment of the Space Station. Tight environmental control will be maintained while data on gas exchange rates and biomass accumulation rates are collected. In order to obtain an early realistic determination of the subsystem and system requirements necessary to provide the environmental conditions specified for CTF crop productivity experiments, an Engineering Development Unit (EDU) has been designed, constructed and is in the process of subsystem and system testing at NASA Ames Research Center. The EDU is a ground test-bed which will be used to characterize the integrated performance of major subsystem technologies, to evaluate hardware candidates and control strategies required for the CTF, and to further define the ability to meet CTF requirements within present Space Station constraints. This paper reviews the functional requirements for the EDU, and focuses on the performance evaluation and test results of the various subsystems. Preliminary integrated performance results and control system operation are addressed, and plans for future science and technology testing are discussed.

Kliss, Mark H.↗

Commercial Seed Selection and Effectiveness of Sanitization Methods in Preparation for Plant Growth Experiments on the International Space Station

A closed-loop food production system will be important to gain autonomy on long duration space missions. Crop growth experiments in the Veggie plant chamber aboard the International Space Station (ISS) are helping to identify methods and limitations of food production in space. Prior to flight, seeds are surface sterilized to reduce environmental and crew contamination risks.

crop selection↗

Pick-and-Eat Salad-Crop Productivity, Nutritional Value, and Acceptability to Supplement the ISS Food System

The capability to grow nutritious, palatable food for crew consumption during spaceflight has the potential to provide health-promoting, bioavailable nutrients, enhance the dietary experience, and reduce launch mass as we move toward longer-duration missions. However, studies of edible produce during spaceflight have been limited, leaving a significant knowledge gap in the methods required to grow safe, acceptable, nutritious crops for consumption in space. Researchers from Kennedy Space Center, Johnson Space Center, Purdue University and ORBITEC have teamed up to explore the potential for plant growth and food production on the International Space Station (ISS) and future exploration missions. KSC, Purdue, and ORBITEC bring a history of plant and plant-microbial interaction research for ISS and for future bioregenerative life support systems. JSC brings expertise in Advanced Food Technology (AFT), Behavioral Health and Performance (BHP), and statistics. The Veggie vegetable-production system on the ISS offers an opportunity to develop a pick-and-eat fresh vegetable component to the ISS food system as a first step to bioregenerative supplemental food production. We propose growing salad plants in the Veggie unit during spaceflight, focusing on the impact of light quality and fertilizer formulation on crop morphology, edible biomass yield, microbial food safety, organoleptic acceptability, nutritional value, and behavioral health benefits of the fresh produce. The first phase of the project will involve flight tests using leafy greens, with a small Chinese cabbage variety, Tokyo bekana, previously down selected through a series of research tests as a suitable candidate. The second phase will focus on dwarf tomato. Down selection of candidate varieties have been performed, and the dwarf cultivar Red Robin has been selected as the test crop. Four light treatments and three fertilizer treatments will be tested for each crop on the ground, to down select to two light treatments and one fertilizer treatment to test on ISS. Our work will help define light colors, levels, and horticultural best practices to achieve high yields of safe, nutritious leafy greens and tomatoes to supplement a space diet of prepackaged food. Our final deliverable will be the development of growth protocols for these crops in a spaceflight vegetable production system. With this work, and potentially with other pending joint projects, we will continue the synergistic research to help close gaps in the human research roadmap, and enable humans to venture to Mars and beyond. This research was co-funded by the Human Research Program and Space Biology (MTL1075) in the ILSRA 2015 NRA call.

Behavioral Health↗

Farming in space: environmental and biophysical concerns

The colonization of space will depend on our ability to routinely provide for the metabolic needs (oxygen, water, and food) of a crew with minimal re-supply from Earth. On Earth, these functions are facilitated by the cultivation of plant crops, thus it is important to develop plant-based food production systems to sustain the presence of mankind in space. Farming practices on earth have evolved for thousands of years to meet both the demands of an ever-increasing population and the availability of scarce resources, and now these practices must adapt to accommodate the effects of global warming. Similar challenges are expected when earth-based agricultural practices are adapted for space-based agriculture. A key variable in space is gravity; planets (e.g. Mars, 1/3 g) and moons (e.g. Earth's moon, 1/6 g) differ from spacecraft orbiting the Earth (e.g. Space stations) or orbital transfer vehicles that are subject to microgravity. The movement of heat, water vapor, CO2 and O2 between plant surfaces and their environment is also affected by gravity. In microgravity, these processes may also be affected by reduced mass transport and thicker boundary layers around plant organs caused by the absence of buoyancy dependent convective transport. Future space farmers will have to adapt their practices to accommodate microgravity, high and low extremes in ambient temperatures, reduced atmospheric pressures, atmospheres containing high volatile organic carbon contents, and elevated to super-elevated CO2 concentrations. Farming in space must also be carried out within power-, volume-, and mass-limited life support systems and must share resources with manned crews. Improved lighting and sensor technologies will have to be developed and tested for use in space. These developments should also help make crop production in terrestrial controlled environments (plant growth chambers and greenhouses) more efficient and, therefore, make these alternative agricultural systems more economically feasible food production systems. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Review↗

NASA's Contributions to Vertical Farming

NASA and other space agencies have an interest in using plants for human life support in space. The plants could provide food and O2 for the humans, while removing CO2 and helping purify wastewater. Studies to date have shown that a wide range of crops can be grown in controlled environment conditions envisioned for space. These systems will be volume and power constrained and will require recycling of water and nutrients. Light is a critical factor both for crop productivity and system power costs, and recent improvements in LEDs make them a preferred lighting option for space. NASA funded research helped test LEDs for plant lighting beginning in1990 and their continued development for the next 15 years. The explore volume efficiency, concepts such as vertically stacked hydroponic systems and light banks were tested in NASA’s Biomass Production Chamber at Kennedy Space Center, FL, US from 1988 through 2000. This was perhaps one of the first operational vertical farms. Findings from these and related tests around the world date suggest that with ~30-40 mol m-2 day-1 of photosynthetically active radiation, about 20-25 m2 of crops could supply the O2 for one human, while about 50 m2 would be required for food (dietary calories).

Raymond M Wheeler↗

3D Printed Substrate

In preparation for long-term, manned, deep space missions, NASA requires a sustainable system for crop and food production. This system has a variety of benefits, including a fresh food supply, improvements in air quality, a lower need to resupply and psychological benefits for the gardeners. Specifically, NASA is attempting to improve and iterate their Vegetable Production System (VEGGIE), a plant growth unit currently aboard the International Space Station (ISS). The VEGGIE unit is highly dependent on a variety of factors, including passive water delivery, growth lights, rooting pillows and cabin conditions. While previous teams have improved and redesigned water reservoirs, the primary objective of the project was to create a new substrate unit to replace the current rooting pillow design. The current design consists of an electrostatic bag filled with arcillite and a slow-release fertilizer pellet. The prototype design retains the fertilizer pellet for nutrient consistency, however the outer bag and arcillite fillings have been replaced with a 3D printed lattice block. This lattice block has several key points that allow it to function in similar ways to the current design: 1. The lattice planes are porous, with each pore offset such that the overall porosity is the same as the arcillite filling. 2. The block demonstrates a wicking nature and is able to pull water upwards towards the roots. This minimizes time needed to integrate with the existing water reservoir. 3. The filament used is highly flexible and is able to pull apart to accommodate root growth. 4. The lattice planes are connected by microfibers left behind from the printing process. These fibers provide support for the growing roots and keep the lattice planes properly aligned. The substrate block design seeks to reduce the payload costs by being entirely 3D printed. While filament would still need to be provided to the ISS, it is far less expensive than shipping arcillite due to the significantly lower weight. The final design has iterated the lattice plane concept and utilizes vertically placed planes with pores running parallel to the water reservoir. This design has reliably shown water uptake and retention and has been successful in growing multiple romaine lettuce plants. Future work should include further growth testing using multiple plant species, compost and reusability testing, food safety testing and microgravity growth testing.

Affan Bhutta↗

Utilization of potatoes for life support systems in space. III - Productivity at successive harvest dates under 12-h and 24-h photoperiods

Efficient crop production for controlled ecological life support systems requires near-optimal growing conditions with harvests taken when production per unit area per unit time is maximum. This maximum for potato was determined using data on Norland plants which were grown in walk-in growth rooms under 12-h and 24-h photoperiods at 16 C. Results show that high tuber production can be obtained from potatoes grown under a continuous light regime. The dry weights (dwt) of tuber and of the entire plants were found to increase under both photoperiods until the final harvest date (148 days), reaching 5732 g tuber dwt and 704 g total dwt under 12-h, and 791 g tuber dwt and 972 g total dwt under 24-h.

Wheeler, Raymond M.↗

Preparation for Pick-and-Eat Food Production on the International Space Station: Flight Definition for the VEG-04 and VEG-05 Missions

Growth of fresh, nutritious, palatable produce for crew consumption during spaceflight may provide health-promoting, bioavailable nutrients and enhance the dietary experience as we move toward longer-duration missions. Tending plants also may serve as a countermeasure for crew psychological stresses associated with long duration spaceflight. However, requirements to support consistent growth of a variety of high quality, nutritious crops under spaceflight environmental conditions is unknown. This study is exploring the potential to grow plants for food production on the International Space Station (ISS) using the Veggie vegetable production system. Ground testing is underway to compare the impacts of several fertilizer and lighting treatments on growth, quality, and nutritional composition of the leafy green crop mizuna, and the dwarf tomato crop Red Robin when subjected to Veggie ISS environmental conditions. Early testing focused on the leafy crop Tokyo Bekana Chinese cabbage, but ground tests indicated that this plant suffered from stress responses when grown under LEDs and the chronically elevated CO2 levels found on the ISS. Mizuna, a related leafy variety that grows well in the presence of high CO2, and has excellent organoleptic characteristics, was selected as an alternate crop. Tomato crops have been grown using two fertilizer formulations and two pollination techniques, and growth tests using different red:blue lighting environments are underway. Chemical analysis is also being conducted and these data, when coupled with the growth results, will be used to down-select to the two best lighting treatments and best fertilizer treatment for future testing of each crop on the ISS. Additionally, seed-source testing has become important, with mizuna seeds from two different vendors growing very differently. A seed source has been selected, and seed-surface-sanitizing methods have been confirmed for mizuna, but these remain under development for tomato. A crop-handling protocol is also being evaluated to support food safety. All harvests reserve a subset of samples for microbial analysis to determine baseline microbial levels and help establish critical control points for food safety. Testing was initially conducted in hardware analogs of the standard Veggie plant pillows. However, a new Veggie watering system, the Passive Orbital Nutrient Delivery System or PONDS, has been designed and is being prepared for future flight experiments. With the selection of this growth system, ground tests have shifted to analog PONDS systems. Crop tests on ISS, designated VEG-04 for mizuna and VEG-05 for tomato, are planned in 2018 to evaluate any additional impacts of spaceflight on the light and fertilizer conditions down-selected from ground tests. A set of Veggie-specific questions has been developed to characterize the psychological impacts of plant growth and plant-care activities during spaceflight. Organoleptic questionnaires have been developed to assess produce attributes in microgravity taste sessions. These tests for plants growing in the Veggie hardware on ISS will help to mitigate the risk of an inadequate food supply for long duration missions by developing methods and determining hardware requirements to integrate fresh vegetables as a dietary supplement. This research was co-funded by the Human Research Program and Space Biology (MTL1075) in the ILSRA 2015 NRA call.

Veggie↗

Preparation for Pick-and-Eat Food Production on the International Space Station: Flight Definition for the VEG-04 and VEG-05 Missions

Growth of fresh, nutritious, palatable produce for crew consumption during spaceflight may provide health-promoting, bioavailable nutrients and enhance the dietary experience as we move toward longer-duration missions. Tending plants also may serve as a countermeasure for crew psychological stresses associated with long duration spaceflight. However, requirements to support consistent growth of a variety of high quality, nutritious crops under spaceflight environmental conditions is unknown. This study is exploring the potential to grow plants for food production on the International Space Station (ISS) using the Veggie vegetable production system. Ground testing is underway to compare the impacts of several fertilizer and lighting treatments on growth, quality, and nutritional composition of the leafy green crop mizuna, and the dwarf tomato crop "Red Robin" when subjected to Veggie ISS environmental conditions. Early testing focused on the leafy crop "Tokyo Bekana" Chinese cabbage, but ground tests indicated that this plant suffered from stress responses when grown under LEDs and the chronically elevated CO2 levels found on the ISS. Mizuna, a related leafy variety that grows well in the presence of high CO2, and has excellent organoleptic characteristics, was selected as an alternate crop. Tomato crops have been grown using two fertilizer formulations and two pollination techniques, and growth tests using different red:blue lighting environments are underway. Chemical analysis is also being conducted and these data, when coupled with the growth results, will be used to down-select to the two best lighting treatments and best fertilizer treatment for future testing of each crop on the ISS. Additionally, seed-source testing has become important, with mizuna seeds from two different vendors growing very differently. A seed source has been selected, and seed-surface-sanitizing methods have been confirmed for mizuna, but these remain under development for tomato. A crop-handling protocol is also being evaluated to support food safety. All harvests reserve a subset of samples for microbial analysis to determine baseline microbial levels and help establish critical control points for food safety. Testing was initially conducted in hardware analogs of the standard Veggie plant pillows. However, a new Veggie watering system, the Passive Orbital Nutrient Delivery System or PONDS, has been designed and is being prepared for future flight experiments. With the selection of this growth system, ground tests have shifted to analog PONDS systems. Crop tests on ISS, designated VEG-04 for mizuna and VEG-05 for tomato, are planned in 2018 to evaluate any additional impacts of spaceflight on the light and fertilizer conditions down-selected from ground tests. A set of Veggie-specific questions has been developed to characterize the psychological impacts of plant growth and plant-care activities during spaceflight. Organoleptic questionnaires have been developed to assess produce attributes in microgravity taste sessions. These tests for plants growing in the Veggie hardware on ISS will help to mitigate the risk of an inadequate food supply for long duration missions by developing methods and determining hardware requirements to integrate fresh vegetables as a dietary supplement. This research was co-funded by the Human Research Program and Space Biology (MTL#1075) in the ILSRA 2015 NRA call.

LED light↗

Preparing for Veg-04 and Veg-05: Improving Pick-And-Eat Food Capabilities for the International Space Station

The capability to grow nutritious, palatable food for crew consumption during spaceflight has the potential to provide health-promoting, bioavailable nutrients, enhance the dietary experience, and reduce launch mass as we move toward longer-duration missions. Studies of edible produce during spaceflight have been limited, leaving a significant knowledge gap in the methods required to grow safe, acceptable, nutritious crops for consumption in space. Researchers from Kennedy Space Center, Johnson Space Center, Purdue University and ORBITEC have teamed up to explore the potential for plant growth and food production on the International Space Station (ISS) and future exploration missions. Ground testing of Chinese cabbage and dwarf tomato crops under different LED lighting and fertilizer conditions is being conducted to allow for a preliminary down selection of the two best lighting recipes and the best fertilizer treatment. Two trials of Chinese cabbage and one trial on dwarf tomato have been completed in on-going ground tests. Horticultural data on crop growth and productivity and chemical data on specific nutrients have been collected and are being analyzed to allow preliminary down selection. Taste test evaluations are planned on the preliminary down selection treatments to allow a final down selection for flight testing. Microbial assessment for hazard analysis critical control points (HACCP) evaluation is also underway to enable implementation of food consumption. Following down selection flight preparation will commence for testing these crops in the Veggie vegetable-production system on the ISS. A crew questionnaire has been developed to better understand the impact of crop growth in Veggie on crew behavioral health. A single Veggie plant growth chamber is currently installed on ISS, and preparations are underway to launch a second Veggie, allowing side-by-side testing under different lighting conditions. Veg-04 will be the first mission that will use this dual-Veggie capability, where the selected cultivar of Tokyo bekana Chinese cabbage will be grown under two different red-to-blue light ratios. ORBITEC has developed custom lighting software allowing independent selection of red and blue light levels. The VEG-05 experiment will test similar light treatments using Red Robin dwarf tomato. These tests offer an opportunity to develop a pick-and-eat fresh vegetable component to the ISS food system as a first step to regular supplemental food production. Our work will help define light colors, levels, and horticultural best practices to achieve high yields of safe, nutritious leafy greens and tomatoes to supplement a space diet of prepackaged food. With this work we will continue the synergistic research to help close gaps in the human research roadmap, and enable humans to venture to Mars and beyond. This research was co-funded by the Human Research Program and Space Biology (MTL1075) in the ILSRA 2015 NRA call.

International Space Station↗

Plant Growth Research for Food Production: Development and Testing of Expandable Tuber Growth Module

Controlled and reliable growth of a variety of vegetable crops is an important capability for manned deep space exploration systems for providing nutritional supplementation and psychological benefits to crew members. Because current systems have been limited to leafy vegetables that require minimal root space, a major goal for these systems is to increase their ability to grow new types of crops, including tuber plants and root vegetables that require a large root space. An expandable root zone module and housing was developed to integrate this capability into the Vegetable Production System (Veggie). The expandable module uses a waterproof, gas-permeable bag with a structure that allows for root space to increase vertically throughout the growth cycle to accommodate for expanding tuber growth, while minimizing the required media mass. Daikon radishes were chosen as an ideal tuber crop for their subterraneous tuber size and rapid growth cycle, and investigations were done to study expanding superabsorbent hydrogels as a potential growth media. These studies showed improved water retention, but restricted oxygen availability to roots with pure gel media. It was determined that these hydrogels could be integrated in lower proportions into standard soil to achieve media expansion and water retention desired. Using the constructed module prototype and ideal gel and soil media mixture, daikon radishes are being grown in the system to test the capability and success of the system through a full growth cycle.

food production↗

Plant productivity and characterization of zeoponic substrates after three successive crops of radish

The National Aeronautics and Space Administration (NASA) has developed advanced life support (ALS) systems for long duration space missions that incorporate plants to regenerate the atmosphere (CO2 to O2), recycle water (via evapotranspiration), and produce food. NASA has also developed a zeolite-based synthetic substrate consisting of clinoptilolite and synthetic apatite to support plant growth for ALS systems (Ming et al., 1995). The substrate is called zeoponics and has been designed to slowly release all plant essential elements into "soil" solution. The substrate consists of K- and NH4-exchanged clinoptilolite and a synthetic hydroxyapatite that has Mg, S, and the plant-essential micronutrients incorporated into its structure in addition to Ca and P. Plant performance in zeoponic substrates has been improved by the addition of dolomite pH buffers, nitrifying bacteria, and other calcium-bearing minerals (Henderson et al., 2000; Gruener et al., 2003). Wheat was used as the test crop for all of these studies. The objectives of this study were to expand upon the previous studies to determine the growth and nutrient uptake of radish in zeoponic substrates and to determine the nutrient availability of the zeoponic substrate after three successive radish crops.

Gruener, J. E.↗