Across India, agricultural officers and crop scientists are flagging a growing but often overlooked problem: micronutrient deficiency in crops. Soil testing data from multiple states show that even fields with adequate NPK fertiliser use are reporting yield loss, poor grain quality, and weak plant growth. The reason is simple—critical micronutrients like zinc, boron, iron, and sulphur are missing or imbalanced in many soils. As climate stress, intensive farming, and fertiliser misuse increase, micronutrient deficiency is no longer a minor issue. It is directly affecting farm income, crop resilience, and food quality today.
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| Micronutrient Deficiency in Crops |
What Are Micronutrients and Why Do They Matter?
Micronutrients are essential elements required by plants in small quantities, but their role is critical. Unlike nitrogen or phosphorus, these nutrients regulate enzyme activity, photosynthesis, flowering, and grain formation.
Key micronutrients for crops include:
Zinc (Zn)
Boron (B)
Iron (Fe)
Manganese (Mn)
Copper (Cu)
Molybdenum (Mo)
Sulphur (S) (often classified as secondary, but widely deficient)
A deficiency in any one of these can limit crop performance even if major nutrients are sufficient. This is why many farmers see poor results despite applying recommended fertiliser doses.
Most Common Micronutrient Deficiencies in Indian Crops
Zinc Deficiency: The Most Widespread Problem
Zinc deficiency is reported in more than 40% of Indian agricultural soils, especially in rice–wheat systems.
Common symptoms:
Yellowing between leaf veins
Stunted plant growth
Poor tillering in rice
Small grains in wheat and maize
Zinc deficiency reduces yield directly and also affects nitrogen use efficiency, meaning applied fertiliser is wasted.
Boron Deficiency: A Major Cause of Poor Flowering
Boron deficiency is common in light, sandy soils and areas with high rainfall.
Symptoms include:
Flower and fruit drop
Hollow or cracked stems
Poor seed formation in mustard, sunflower, and vegetables
In oilseeds and pulses, boron deficiency can cut yield by 20–30% without obvious early warning signs.
Iron Deficiency: Increasing in High-pH Soils
Iron deficiency is increasingly seen in alkaline and calcareous soils, especially in parts of north and western India.
Typical signs:
Yellowing of young leaves (interveinal chlorosis)
Weak plant growth
Reduced photosynthesis
Crops like rice, groundnut, soybean, and citrus are particularly sensitive.
Sulphur Deficiency: A Hidden Yield Reducer
With reduced use of sulphur-containing fertilisers, sulphur deficiency has become common in cereals and oilseeds.
Indicators:
Pale yellow leaves resembling nitrogen deficiency
Delayed maturity
Lower oil content in mustard and groundnut
Sulphur is essential for protein synthesis and oil formation, making it critical for both yield and quality.
Why Micronutrient Deficiency Is Increasing Now
Several factors are driving the rise in micronutrient imbalance:
Continuous cropping without soil replenishment
Overuse of high-analysis fertilisers like urea and DAP
Decline in organic matter application
High soil pH due to irrigation water and lime use
Climate stress affecting nutrient uptake
In many regions, farmers focus on visible deficiencies, but micronutrient stress often remains hidden until harvest losses appear.
Crops Most Affected by Micronutrient Deficiency
Micronutrient issues do not affect all crops equally. High-risk crops include:
Rice and wheat (zinc, iron)
Mustard and groundnut (boron, sulphur)
Pulses (molybdenum, boron)
Vegetables and fruits (iron, zinc, calcium interactions)
Sugarcane (zinc, iron)
High-yielding varieties are especially sensitive because they remove more nutrients from soil.
How Farmers Can Identify and Manage Deficiency
Soil and Leaf Testing
Regular soil testing remains the most reliable method. Leaf analysis during critical growth stages provides early warning before yield loss.
Balanced Fertilisation
Apply micronutrients based on soil test results, not guesswork. Excess application can be as harmful as deficiency.
Correct Application Methods
Zinc: Soil application or foliar spray at early growth stages
Boron: Low-dose soil or foliar application, avoid overuse
Iron: Foliar sprays are more effective in high-pH soils
Sulphur: Use sulphur-containing fertilisers or gypsum
Organic Matter Management
Farmyard manure, compost, and green manuring improve micronutrient availability and soil health over time.
Why This Matters for Food Security and Farmer Income
Micronutrient deficiency is not just a farm-level issue. It affects national productivity, grain quality, and nutritional value of food. Lower protein content in cereals and poor oil recovery in oilseeds directly impact market returns. Addressing micronutrient gaps is one of the most cost-effective ways to improve yields without expanding land or water use.
Conclusion
Micronutrient deficiency is now a mainstream agricultural challenge in India, not a niche concern. Zinc, boron, iron, and sulphur deficiencies are reducing crop yields silently across regions and crops. The solution lies in soil testing, balanced nutrient management, and moving beyond NPK-only thinking. Farmers who address micronutrient needs early are seeing better yields, stronger crops, and more stable income. Ignoring these small nutrients is no longer an option in modern farming.
