High concentrations of some minerals in irrigation water may cause foliar injury to crops.
The minerals of primary concern are sodium (Na), chloride (Cl), and boron (B).
Sprinkler irrigation water containing high concentrations of these minerals may cause
leaf burn when applied to growing crops. In general, concentrations should not exceed
70 mg Na/L, 105 mg Cl/L, and 0.7 mg B/L for sensitive crops or 200 mg Na/L, 350 mg
Cl/L, and 2.0 mg B/L for moderately tolerant crops. Factors that increase the degree of
leaf injury from Na, Cl, and B are high concentrations of these minerals in the water,
high air temperature, low relative humidity, and high wind speed.
Surface applied irrigation water high in soluble salts and sodium may adversely affect
crop productivity by increasing the electrical conductivity (ECe) and the exchangeable
sodium percentage (ESP) of the soil. Please refer to the section on Management
Practices for Irrigation with Saline or Sodic Water for additional information. ECe and
ESP values increase in soil primarily from the presence of high concentrations of Na
and Cl in irrigation water and/or from a high-water table with elevated concentrations of
Na and Cl. Please refer to our website, www.amaglab.com, for additional information
regarding salinity, sodium, chloride, and boron toxicity guidelines.