Figure 1.

Effect of pH and content of organic matter on the availability of Si(OH)₄ in soil (A,D), concentration of Si (as SiO₂) in plant dry weight (B,E), and its accumulation in the tomato plant (C,F) under two conditions of average soil temperature: 15°C (A–C) and 25 ° C (D–F). Data obtained from the proposed dynamic model considering as inputs of the growth model: PAR = 400 μmol m⁻² s⁻¹ (12 h per day); CO₂ = 400 ppm; and Temperature: 30°C. As soil conditions were considered: a soil profile of 30 cm, soil humidity of 25% (w/w), and availability of Si as Si(OH)₄ in irrigation water of 5 mg L⁻¹.