Over-expression of FT1 in plum (Prunus domestica) results in phenotypes compatible with spaceflight: a potential new candidate crop for bioregenerative life support systems

Authors: GRAHAM, THOMAS - National Aeronautics And Space Administration (NASA); Scorza, Ralph; WHEELER, RAYMOND - National Aeronautics And Space Administration (NASA); SMITH, BRENDA - University Of Oklahoma; Dardick, Christopher - Chris; DIXIT, ANIRUDHA - National Aeronautics And Space Administration (NASA); Raines, Charles - Doug; Callahan, Ann; Srinivasan, Chinnathambi; SPENCER, LASHELLE - National Aeronautics And Space Administration (NASA); RICHARDS, JEFFREY - National Aeronautics And Space Administration (NASA); STUTTE, GARY - National Aeronautics And Space Administration (NASA)

Submitted to: Gravitational and Space Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/1/2015
Publication Date: 7/27/2015
Citation: Graham, T., Scorza, R., Wheeler, R., Smith, B., Dardick, C.D., Dixit, A., Raines, C.D., Callahan, A.M., Srinivasan, C., Spencer, L., Richards, J., Stutte, G. 2015. Over-expression of FT1 in plum (Prunus domestica) results in phenotypes compatible with spaceflight: a potential new candidate crop for bioregenerative life support systems. Gravitational and Space Research. 3(1):39-50.

Interpretive Summary: Tree fruits (e.g., apples, plums, cherries) are appealing constituents of a crew menu for long-duration exploration missions (i.e., Mars), both in terms of their nutritive value, and a diversity of menu items which is an important psychological aspect of long periods traveling through space. Although appealing in these respects, tree fruits have long been passed-over as suitable crops for use in long-duration space travel because of their large size, the long period of time between fruiting periods, and their need for a long winter dormancy period. Recent advances by researchers at the United States Department of Agriculture (USDA), Agricultural Research Service (ARS) have led to the development of plum trees expressing a flowering gene normally found in poplar trees. These plum trees are dwarf, produce flowers and fruit year-round, and do not require a dormancy period. In addition, the health benefits of plums, fresh and dried, have been well documented. In particular, the positive effects of dried plums on bone density would be a real advantage in long-duration space flight because bone density loss is a major challenge for astronauts. Through a partnership between USDA-ARS, National Aeronautics and Space Administration (NASA), and the University of Oklahoma, these plum trees are being tested as an exciting new system for developing fruit trees for long-duration space travel and for Mars colonies.

Technical Abstract: Tree fruits (e.g., apples, plums, cherries) are appealing constituents of a crew menu for long-duration exploration missions (i.e., Mars), both in terms of their nutritive and menu diversity contributions. Although appealing, tree fruit species have long been precluded as candidate crops for use in plant-based bio-regenerative life-support system designs based on their large crown architecture, prolonged juvenile phase, and phenological constraints. Recent advances by researchers at the United States Department of Agriculture (USDA) have led to the development of plum (Prunus domestica) trees ectopically over-expressing the Flowering Locus T-1 (FT1) gene from Populus trichocarpa (poplar). The transformed plants exhibit atypical phenotypes that seemingly eliminate the aforementioned obstacles to spaceflight. Here we demonstrate the FT1 expression system (FasTrack) and the resultant dwarf growth habits, early flowering, and continuous fruit production. The potential contribution of P. domestica as a countermeasure to microgravity-induced bone loss is also discussed.