The concentration of mineral elements in plants varies depending on the plant species, tissue type (roots, leaves, stems, etc.), soil composition, and environmental conditions. Mineral elements are classified as either macronutrients (required in larger amounts) or micronutrients (required in trace amounts).
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Major Mineral Elements in Plants (Macronutrients)
These are required in relatively high concentrations (> 0.1% of dry weight):
1. Nitrogen (N) – 1.5–6%
– Key component of amino acids, proteins, and chlorophyll.
2. Potassium (K) – 1–5%
– Important for osmotic regulation and enzyme activation.
3. Calcium (Ca) – 0.2–3.5%
– Structural role in cell walls; signaling molecule.
4. Magnesium (Mg) – 0.1–0.8%
– Central atom in chlorophyll; enzyme cofactor.
5. Phosphorus (P) – 0.1–0.8%
– Part of ATP, nucleic acids, and phospholipids.
6. Sulfur (S) – 0.1–0.5%
– Component of cysteine, methionine, and coenzymes.
Trace Mineral Elements (Micronutrients)
These are required in very small amounts (< 0.01% of dry weight):
1. Iron (Fe) – 50–300 ppm
– Essential for chlorophyll synthesis and electron transport chains.
2. Manganese (Mn) – 20–500 ppm
– Activates enzymes in photosynthesis and respiration.
3. Zinc (Zn) – 20–100 ppm
– Involved in auxin synthesis and enzyme function.
4. Copper (Cu) – 5–30 ppm
– Required for photosynthesis and lignin formation.
5. Boron (B) – 10–100 ppm
– Important for cell wall structure and sugar transport.
6. Molybdenum (.jpg)
– 0.1–10 ppm
– Needed for nitrogen fixation and nitrate reduction.
Factors Affecting Mineral Concentration
– Soil availability – Poor or imbalanced soil reduces uptake.
– pH – Affects solubility; e.g., Fe is less available in alkaline soils.
– Plant species