Dec 27, 2014

Dissolve the desired mass of salicylic acid in 1 L of water.

Salicylic acid (SA) inhibits the accumulation of Na⁺ and Cl⁻ in plants.

Most researchers have used concentrations ranging from 0.25 mmol/L to 180 mmol/L.

Assume that you want to use 1.00 mmol/L SA.

$\text{1.00 mM SA" = (1.00 × 10^-3"mol SA")/"1 L" × "138.12 g SA"/"1 mol SA" = "0.138 g SA/L" = "138 mg SA/L}$

So you would dissolve 138 mg of SA in 1 L of distilled water.

SA is slightly soluble in water. You may wish to dissolve it first in about 2 drops of dimethyl sulfoxide. Then add the water.

Some researchers use distilled water containing Polysorbate 20 (200 mg/L).

Polysorbate is a surfactant. I presume that it facilitates absorption of SA by the plant.