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Due to its large proportion of edible biomass, beet (Beta vulgaris) has high potential as a candidate crop for bioregenerative life support systems. This paper summarizes data collected for beet under batch and staged stand culture in closed environment chambers. Full stand trials were conducted under the following conditions: 1000 μL L−1 atmospheric carbon dioxide concentration, light intensities ranging from 400–600 μmol m−2 s−1 PAR with a 14 hour photoperiod, 73% ± 5% relative humidity, a 26/20 °C day/night temperature regime and a fixed planting density of 17.6 plants m−2. For batch planted stands, total edible yield was determined to be 28.3 g dry weight basis (dwb) with a 95% Confidence Interval (CI) of [24.7, 31.8] g plant−1 with a harvest index of 94%. Under similar conditions, yield for staged beet stands was 31.4 g dwb with a 95% CI of [24.54, 38.31] g plant−1. Water use efficiency under these same conditions was found to be 0.003 mol C mol−1 H2O.

It is understood that plants and microorganisms will be an intrinsic part of future advanced life support (ALS) systems. The photosynthetic process is uniquely able to provide food and water from transpiration, remove carbon dioxide, and produce oxygen. However, atmospheric management with typical monoculture batch plant growth is made difficult due to fluctuating rates of CO2 assimilation and O2 production during different phases of plant growth and development. Experiments on the effect of continuous production of multiple crops with rotational planting on atmospheric stability within a sealed environment were performed in the Controlled Environment Systems Research Facility ambient pressure controlled environment chambers. Two of the ESA-MELiSSA candidate crops, beet and lettuce, were continuously grown with a ten day staggered planting interval, resulting in a plant canopy with all representative stages of physiological growth within a common atmosphere.

In dense plant canopies, shaded leaves represent considerable unused photosynthetic capacity that can be exploited to improve production in closed environments. By coupling Fusion Systems Solar 1000 microwave powered lights to 100 mm diameter glass tubes lined with 3M Optical Lighting Film, energy equivalent to approximately 420 μmol m-2 s-1 PAR was delivered to the inner canopy of a developing soybean (Glycine max L. Merr. cv. Secord) crop. Inner canopy irradiation enhanced plant growth and altered biomass partitioning within the canopy. With inner canopy lighting, edible biomass, carbon dioxide removal and water and oxygen production were increased by 9, 30, 160, and 100 percent respectively. Ethylene production in the closed environment was also increased during several months of canopy development.