Influence of the Modification of Nutritional Parameters in Aglaonema commutatum: K⁺, Ca²⁺, Mg²⁺ and Na⁺

Abstract

This trial was carried out to establish an appropriate nutrient solution for Aglaonema commutatum and to investigate the nutritional effects generated by modifications in the solution. Six treatments were tested: control (T₀; pH 6.5, E.C. 1.5 dS m⁻¹, 6 mmol L⁻¹ NO₃ ⁻‐N, and 6 mmol L⁻¹ K⁺); high nitrogen (N) level (T₁; 9 mmol L⁻¹ 6:3 NO₃ ⁻–NH₄ ⁺); N form (T₂; 6 mmol L⁻¹ N‐NH₄ ⁺); high K⁺ level (T₃; 12 mmol L⁻¹ K⁺); high electrical conductivity (T₄; E.C. 4 dS m⁻¹, 25 mmol L⁻¹ NaCl), and basic pH (T₅; pH 8). At the end of the cultivation, leaf, shoot, and root dry weights and elemental concentrations were determined. Nutrient contents and total plant uptake were calculated from the dry weights and nutrient concentrations. Plant K⁺ uptake increased with application of K⁺ or basic nutrient solution. The uptake and transport of calcium (Ca) were enhanced by the use of NO₃ ⁻‐N and inhibited by the presence of other cations in the medium (NH₄ ⁺, K⁺, Na⁺) and by basic pH. Magnesium (Mg) uptake increased with NO₃ ⁻‐N application and with pH. Sodium (Na) uptake was the highest in the saline treatment (T₄), followed by the basic pH treatment. Sodium accumulation was detected in the roots (natrophobic plant), where the plant generated a physiological barrier to avoid damage. Dry weight did not differ significantly (p<0.05) among treatments except in the NaCl treatment. These results may help in the formulation of nutrient solutions that take into account the ionic composition of irrigation water and the physiological requirements of plants.

Keywords:

• Closed system
• electrical conductivity
• pH
• N‐form
• ornamental crop