PLANTS ARE PRIMARY PRODUCERS OF FOOD AND OXYGEN ON EARTH AND WILL LIKEWISE BE INDISPENSABLE TO THE ESTABLISHMENT OF LARGESCALE SUSTAINABLE ECOSYSTEMS AND HUMAN SURVIVAL ON EXTRATERRESTRIAL SURFACES. OWING TO THEIR SMALL VOLUME AND MINIMAL STORAGE REQUIREMENTS SEEDS ARE THE MOST CONVENIENT MEANS OF PLANT TRANSPORTATION IN SPACE. HOWEVER THROUGH YET-LARGELY UNKNOWN MECHANISMS SPACEFLIGHT AFFECTS SEED QUALITY AND CONSEQUENTLY THE VIGOR OF SEEDLINGS. THEREFORE MORE RESEARCH IS NEEDED TO FULLY UNDERSTAND SEED BIOLOGY RESPONSES TO SPACEFLIGHT AND ULTIMATELY MAKE PLANTS A SUSTAINABLE SOURCE OF OXYGEN AND FOOD IN SPACE. TO INCREASE FUNDAMENTAL KNOWLEDGE OF PLANTS RESPONSES TO SPACEFLIGHT AND TO FACILITATE GERMPLASM SELECTION FOR EXTENDED SPACEFLIGHT AND EXTRATERRESTRIAL COLONIZATION IN THIS PROPOSAL WE PLAN TO TEST THE EFFECT OF SPACEFLIGHT IN THE EM-1 ORION CAPSULE ON ARABIDOPSIS THALIANA SEEDS ENRICHED NUTRIENT STORES SPECIFICALLY ELEVATED LEVELS OF BRANCHED-CHAIN AMINO ACIDS (BCAAS). THESE ESSENTIAL NUTRIENTS SERVE AS STORAGE RESERVES FOR THE SEEDS AND SEEDLINGS. GENERALLY SEEDS WITH HIGH LEVELS OF NUTRIENTS ARE MORE LIKELY TO GERMINATE AND PRODUCE HEALTHY SEEDLINGS THAN SEEDS WITH LOW NUTRIENT CONTENT. ADDITIONALLY DEVELOPMENT OF SEEDS WITH HIGH LEVELS OF NUTRIENTS IS IMPORTANT TO PROVIDE A COMPACT AND EFFICIENT NOURISHMENT TO HUMANS. BECAUSE SPACEFLIGHT CONDITIONS CAN IMPOVERISH THE NUTRIENT RESERVES OF SEEDS WE THEREFORE HYPOTHESIZE THAT SEEDS WITH INCREASED LEVELS OF BCAAS WILL NOT ONLY BETTER ENDURE SPACEFLIGHT-ASSOCIATED STRESS AND PRODUCE HEALTHIER SEEDLINGS BUT COULD ALSO SUPPLY A GREATER PROPORTION OF MISSION-CRITICAL DIETARY REQUIREMENTS. SUCCESSFUL ACCOMPLISHMENT OF OUR RESEARCH WHICH IS GROUNDED UPON OUR EXPERIENCE WITH SPACEFLIGHT WITH NASA BRIC-UNITS AND A. THALIANA WILL INCREASE BASIC KNOWLEDGE OF THE EFFECTS OF SPACEFLIGHT ON FUNDAMENTAL PLANT METABOLISM. WE EXPECT THAT OUR RESULTS WILL ALSO SET IMPORTANT FOUNDATIONS FOR TRANSLATABLE PRINCIPLES NEEDED TO INCREASE PLANT NUTRITIONAL VALUE AND CULTIVATION IN SPACEFLIGHT FOR THE LONG-TERM COLONIZATION OF EXTRATERRESTRIAL SURFACES BY HUMANS.