Nickel (Ni) is an essential trace element in plant nutrition, playing a critical role in nitrogen metabolism, enzyme activation, and overall plant health. Although required in small quantities, nickel deficiency can significantly impact crop performance, particularly in legumes and cereals that rely on nitrogen fixation.
1. Importance of Nickel in Plant Growth
Nickel is a key component of the enzyme urease, which converts urea into usable ammonium nitrogen for plant uptake. It also enhances seed germination, nitrogen assimilation, and resistance to toxic levels of other metals. Adequate nickel nutrition improves overall nutrient balance and crop vigor.
Key roles of nickel include:- Urease activation: Enables the conversion of urea into ammonium, preventing urea accumulation and leaf necrosis.
- Nitrogen metabolism: Supports symbiotic nitrogen fixation in legumes and enhances nitrogen use efficiency.
- Seed and grain development: Promotes enzyme activity that influences protein formation and seed quality.
- Stress tolerance: Helps plants resist environmental and metal stress by regulating enzymatic reactions.
2. Forms of Nickel Fertilizers
Nickel fertilizers are available in both inorganic and chelated forms to ensure efficient plant uptake.
2.1 Inorganic Nickel Fertilizers
- Advantages: Quick nutrient release, suitable for foliar and soil applications.
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Best for: Correcting acute nickel deficiency in legumes and high-nitrogen-demand crops.
2.2 Chelated Nickel Fertilizers
- Advantages: Improved stability, enhanced bioavailability, and reduced risk of soil fixation.
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Best for: Alkaline or high-pH soils where nickel availability is limited.
3. Application Methods and Best Practices
- Soil Application: Apply nickel fertilizers near the root zone for efficient absorption, especially in sandy or calcareous soils.
- Foliar Spraying: Recommended for rapid correction of nickel deficiency and better uptake efficiency.
- Seed Treatment: Coating seeds with low-dose nickel can enhance germination and early seedling vigor.
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Integrated Nutrient Management: Combine nickel with balanced macronutrient and micronutrient fertilizers to maximize efficiency.
4. Symptoms of Nickel Deficiency
Nickel deficiency is relatively rare but can occur in specific conditions such as sandy soils, low organic matter, or excessive liming.
Common signs include:
- Accumulation of urea in leaf tips causing necrosis (“mouse-ear” symptom in pecans).
- Poor seed germination and reduced vigor.
- Chlorosis in young leaves.
- Reduced nitrogen fixation in legumes.
5. Factors Affecting Nickel Availability
- Soil pH: High pH soils reduce nickel solubility and uptake.
- Organic matter: Low organic matter reduces nickel retention and bioavailability.
- Soil texture: Sandy soils are more prone to nickel leaching.
- Nutrient interactions: Excess phosphorus, zinc, or iron can suppress nickel absorption.
6. Correcting and Preventing Nickel Deficiency
- Apply nickel sulfate or chelated nickel based on soil test recommendations.
- Maintain balanced soil pH (6.0–7.0) to optimize micronutrient availability.
- Incorporate organic amendments to enhance soil microbial activity and metal chelation.
- Rotate crops with legumes to promote natural nickel cycling and nitrogen fixation efficiency.
7. Environmental and Technological Considerations
Table of Contents
Recommended Fertilizers
Urea Fertilizer
View Solutions Urea Fertilizer
View Solutions Urea Fertilizer
View Solutions Urea Fertilizer
View SolutionsSuitable Crops
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