Legume Crop Testing for Space

Long-duration missions beyond low-Earth orbit will encounter challenges in maintaining adequate nutrition and acceptability in the food system. In situ production of fresh produce can supplement nutrient deficiencies in the prepackaged diet. Currently there is a relatively small number of crops that can be reliably grown in space for space crop production efforts. Recent challenges with Veggie plant growth technical demonstrations, such as interveinal chlorosis and necrosis of Tokyo Bekana Chinese cabbage when grown under elevated CO2 (~3000 ppm) and narrow-band LED lighting, have highlighted the necessity to conduct rigorous ISS-relevant crop screening on the ground. Additionally, crops should be selected to address specific nutritional deficits as identified by the Human Research Program, with an emphasis on having a diversity of crops to meet nutritional requirements and crew acceptability. To achieve this, the concept of Crop Readiness Level (CRL) has been developed to gauge readiness of crops for spaceflight applications. This includes assessing environmental compatibility, food safety considerations, relevant nutritional analysis, and sensory analysis. Recent testing at Kennedy Space Center has focused on the advancement of a variety of legumes along the CRL. Five varieties of peas (Pisum sativum) ‘Tom Thumb’, ‘Royal Snap’, ‘Yellow Snap’, ‘ES Thick Pod 404-51-2’ and ‘ES Thick Pod 404-52-2-1’ and three varieties of bean (Phaseolus vulgaris); ‘Antigua’, ‘4921 snap’, and ‘Velour Purple’ were grown under 300 µmol m-1 s-1 PPFD from LED lights, 3000 ppm CO2, and 23°C to simulate an ISS environment. Crops will be harvested and yield, baseline nutritional analysis (Vitamins B1, C, K; elemental analysis; proximate analysis) and sensory evaluation will be performed. These baseline data are essential to selecting candidate crops for future missions in addition to assessing crop production hardware and changes in environmental conditions on future crop performance and nutritional quality.