Primary symptoms

Plants may be wilted, even though soil moisture seems adequate. Leaves may look dull, and the leaf tips or margins may appear to be grayish. If the salt toxicity is severe, the tissue along the leaf margins may become yellow and die.

Confirm the problem by checking the tables below.

Summary

Maize is considered sensitive to salinity. When the electrical conductivity of a saturated soil extract is 2.5 millisiemens/cm (mS/cm, same as millimhos/cm), you can expect a 10% yield reduction; a value of 4 is associated with a 25% yield reduction. This yield loss usually results from the fact that the plants cannot extract enough water from the salt-affected soil. In some cases, the salts are actually toxic to the crop.

Is soil salinity a problem?

Evidence: measurements.

Collect a soil sample and have it tested for electrical conductivity.

Evidence: observations.

1. Look over the field for plants which appear to be wilted, even though soil moisture seems adequate. The leaves may look dull, and the leaf tips or margins may appear to be grayish. If the salt toxicity is severe, the tissue along the leaf margins may become yellow and die.

2. Look for a whitish film of salt on the soil surface, especially on the tops of ridges when the soil is dry in areas where furrow irrigation is used.

Possible solutions

• Leach the soil with clean water to remove the salt accumulation.
• Grow a crop which is less sensitive to salinity. Barley, cotton, and sorghum are all more tolerant than maize. Among maize genotypes, some are more tolerant to salinity than are others.
• Install drainage.
• Modify irrigation scheduling to have fewer irrigations, but with more water applied at each irrigation.