FIGURE 1.

Azolla filiculoides yield potential under continuous production conditions. Ferns were grown with 300 μmol s⁻¹ cm⁻² photosynthetic active radiation at 25°C for the 12 h day and at 22°C during the 12 h night. (A) Closed-canopy cultures with plants in the linear growth phase for continuous harvest. (B) Cumulative dry biomass harvested. Once standing crop formed a closed mat at 160 g m² dry weight, continuous harvest was at a rate of 33% of the biomass twice per week. Linear regression equation is shown along with its fit; n = 6, standard deviations were smaller than the labels.