Occurrence and Prevention of Salt Injury in Chili Peppers (Sweet Peppers)

Main symptoms: Salt injury is prone to occur in saline-alkali areas or in protected cultivation after many years of cropping, causing poor growth and reduced yield in chili peppers. Yellow to brown round or oval necrotic spots appear on the leaves.

Causes: Excessive soil salt concentration causes water and nutrients inside the roots to seep outward, and aboveground growth stops because it cannot obtain water and nutrients; applying too much fertilizer that is difficult to leach, applying organic fertilizer containing large amounts of livestock and poultry manure, and using ammonium chloride, potassium chloride, etc. all lead to increased soil concentration; in protected cultivation, high temperatures and large soil water evaporation make salts in fertilizer prone to rise with capillary water and accumulate in the surface soil layer, and because vegetable roots in protected cultivation are relatively shallow, salt injury is even more likely to occur.

Prevention and control methods: (1) Appropriately reduce the amount of chemical fertilizer applied and apply an appropriate amount of decomposed organic fertilizer. (2) Choose fertilizers that do not easily increase salt concentration, and avoid applying chemical fertilizers containing harmful components, such as ammonium sulfate, etc.