title: Growth of soybean and potato at high CO2 partial pressures.
abstract: Soybean and potato plants were grown in controlled environments at carbon dioxide (CO2) partial pressures ranging from 0.05 to 1.00 kPa. The highest yields of edible biomass occurred at 0.10 kPa for both species, with higher CO2 levels being supraoptimal, but not injurious to the plants. Stomatal conductance rates of upper canopy leaves were lowest at 0.10 kPa CO2, while conductance rates at 0.50 and 1.00 kPa were significantly greater than 0.10 kPa. Total water use by the plants was greatest at the highest CO2 pressures (i.e. 0.50 and 1.00 kPa); consequently, water use efficiencies (biomass produced/water used) were low at the highest CO2 pressures. Based on previous CO2 studies in the literature, the increased conductance and water use at the highest CO2 pressures were surprising and pose interesting challenges for managing plants in a CELSS, where CO2 pressures may exceed optimal levels.
authors.affiliation: Controlled Ecological Life Support Systems Breadboard Project, Biological Research and Life Support Office, Kennedy Space Center, FL 32899, USA.
authors.forename: R M
authors.initials: RM
authors.lastname: Wheeler
authors.forename: C L
authors.initials: CL
authors.lastname: Mackowiak
authors.forename: J C
authors.initials: JC
authors.lastname: Sager
authors.forename: W M
authors.initials: WM
authors.lastname: Knott
mesh_terms: D001274:Atmospheric Pressure; D018533:Biomass; D002245:Carbon Dioxide / Q000378:metabolism / Q000494:pharmacology*; D018504:Ecological Systems, Closed; D004780:Environment, Controlled; D018527:Hydroponics; D010313:Partial Pressure; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D018526:Plant Transpiration; D011198:Solanum tuberosum / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D013025:Glycine max / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D014867:Water / Q000378:metabolism
chemical_list: D014867:Water; D002245:Carbon Dioxide