Selenium (Se)

Role in plants

Selenium is not essential but can enhance antioxidant activity and stress tolerance at low concentrations.

Deficiency symptoms

• None recognised

Toxicity symptoms

• Leaf chlorosis
• Growth suppression
• Leaf necrosis at higher levels

Natural sources

• Selenium-rich parent materials
• Volcanic soils
• Groundwater in some regions

Fertiliser sources

• Sodium selenate
• Sodium selenite

Plant uptake forms

• SeO₄²⁻ (selenate)
• SeO₃²⁻ (selenite)