What it does

Calcium deficiency impairs root function and predisposes plant to iron toxicity. It causes stunting and death of growing points.

Why and where it occurs

Ca deficiency is relatively rare especially in irrigated rice systems. It is very uncommon in lowland rice soils because there is usually sufficient Ca in the soil, from mineral fertilizers, and irrigation water.

Soils particularly prone to Ca deficiency are:

• acid, strongly leached, low-CEC soils in uplands and lowlands
• soils derived from serpentine rocks
• coarse-textured sandy soils with high percolation rates and leaching
• leached, old acid sulfate soils with low base content

How to identify

Signs and symptoms of Ca deficiency are visible only under severe conditions.

• Tips of youngest leaves become white or bleached, rolled, and curled
• Necrotic tissue may develop along the lateral margins of leaves and old leaves eventually turn brown and die
• Stunting and death of growing point during extreme deficiency

To confirm Ca deficiency, bring soil and plant sample to a laboratory for testing.

Click on images to enlarge

Leaf tip discoloration caused by Ca deficiency

How to manage

• Apply farmyard manure or straw (incorporated or burned) to balance Ca removal in soils containing small concentrations of Ca.
• Where possible, use single superphosphate (13-20% Ca) or triple superphosphate (9-14% Ca) as a Ca source.

Learn more

View full fact sheet:
Calcium deficiency on IRRI Rice Knowledge Bank