Fig. 1

Zygopetalum maculatum plants under different treatments (T₁ to T₆ from left to right). T₁ = Distilled water (control = K₀), T₂ = 10 mg L⁻¹ K (K₁₀), T₃ = 25 mg L⁻¹ K (K₂₅), T₄ = 50 mg L⁻¹ K (K₅₀), T₅ = 75 mg L⁻¹ K (K₇₅) and T₆: 100 mg L⁻¹ K (K₁₀₀).