What is a symptom of nitrogen deficiency?

• A. Yellowing of older leaves first
• B. Interveinal yellowing with veins staying green
• C. Browning leaf margins
• D. Wilting

Answer: (A)

Nitrogen is mobile in a plant, so when it’s short, the plant pulls what it needs from older tissue to support new growth. That means the symptoms show up first on the oldest leaves, which turn yellow as chlorophyll breaks down and nutrients are relocated. So yellowing of older leaves first is the telltale sign of nitrogen deficiency.

The other symptoms point to different issues: interveinal yellowing with green veins often comes from micronutrient problems like iron deficiency, browning leaf margins can indicate stress from drought, salt, or potassium imbalance, and wilting is a sign of water stress or root problems rather than a nutrient deficiency.