FIGURE 3.

Influence of Si supply on selected metabolite concentrations in roots of two contrasting tomato genotypes under osmotic stress. (A) Glutamic acid concentration in roots, (B) Gly concentration in roots, (C) Pro concentration in roots, and (D) GABA concentration in roots. Plants were grown in hydroponic culture and osmotic stress was simulated by applying polyethylene glycol (PEG 6000). Si was provided at 0.75 mM for pre-cultured plants and at 1.5 mM for osmotic stressed plants. Roots and fully expanded leaves from 21-day old plants were harvested 7 days after imposition of osmotic stress. Bars indicate means ± SE. Different letters denote significant differences according to Fischer’s LSD test (p < 0.05; n = 4).