Continuous Production of Potato in an AFT System

Abstract

An experiment was conducted in the Biomass Production Chamber (BPC) at Kennedy Space Center to determine the feasibility of continuous steady-state production of potato (Solanum tuberosum L.). Plants were grown in a “batch” or continuous production mode using either 0.5 × modified Hoaglands or effluent from aerobically processed inedible potato biomass as a nutrient source. EC and pH were controlled to 0.12 S·m–1 and 5.8, respectively. The batch harvest occurred after 104 days and continuous harvest occurred every 26 days, with replanting occurring in the same solution. Continuous production on “aged” solution resulted in earlier tuber initiation, reduced plant height, and smaller canopies than the “batch” treatment. Planting density of the continuous treatment was increased from eight to 16 plants/m2. Because one quarter of the planting area was harvested and replanted every 26 days, a steady-state of canopy coverage between 60% to 75% of the chamber was maintained. Steady-state of CO2 fixation was also maintained in the continuous treatment. There was no effect on either quantum efficiency, tuber yield, or harvest index of the plants grown in continuous production. Although replanting into “aged” nutrient solution resulted in earlier tuber initiation and reduced plant size, the system reached a steady state of production, which is desirable for advanced life support system.