Soil Fertility Management. A short description of essential nutrient elements and criteria of essentiality.

1. Soil Fertility
Management
Mr. Aditya Kumar Verma
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2. Topics for
Discussion!
Plant Nutrition
Criteria of Essentiality
Essential Nutrient Elements
Classification of Essential Nutrients
Forms of Nutrients Absorbed by Plants
Level of Nutrient Elements
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3. Plant Nutrition
Nutrients:
Chemical compounds required by an organism.
Plant Nutrition:
The supply and absorption of chemical compounds required for
plant growth and metabolism.
Mineral Nutrient:
The inorganic ion obtained from the soil required for plant growth.
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4. Types of Plant Nutrient Elements
ESSENTIAL
NUTRIENT ELEMENTS
BENEFICIAL
NUTRIENT ELEMENTS
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5. Essential Nutrient Elements
>60
Nutrient elements
absorbed by plants
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Essential for plant
growth and
development
• NOT ALL nutrient elements are Essential for plant’s growth and development.
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6. Criteria of Essentiality
(Arnon & Stout, 1939)
The plant must not be able to complete its life cycle in absence
of this element.
The deficiency of an element is very specific to the element in
question and deficiency can be corrected /prevented only by
supplying that particular element.
The element must be directly involved in the nutrition and
metabolism of the plant.
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7. Essential Nutrient Elements
• An essential nutrient element is the one which is required for
the normal life cycle of an organism and where functions
cannot be substituted by any other chemical compound.
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8. Essential
Nutrient
Elements
Carbon (C) Sulphur (S)
Hydrogen (H) Iron (Fe)
Oxygen (O) Manganese (Mn)
Nitrogen (N) Zinc (Zn)
Phosphorus (P) Copper (Cu)
Potassium (K) Boron (B)
Calcium (Ca) Molybdenum (Mo)
Magnesium (Mg) Chlorine (Cl)
Nickel (Ni)
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9. Classification of Essential
Nutrients
ON THE BASIS OF AMOUNT OF NUTRIENTS
Basic Nutrients
96% of total dry matter of
plants
C, H, O
Macronutrients >0.1% or >1000ppm N, P, K, Ca, Mg, S
Micronutrients <0.1% or <1000ppm Fe, Mn, Zn, Cu, B, Mo, Cl, Ni
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10. Classification of Essential Nutrients
ON THE BASIS OF FUNCTIONS IN PLANT
Structural Elements Provide basic structure to the plant C, H, O
Accessory Structural
Elements
Useful in energy storage, transfer and
bonding
N, P, S
Regulators and Carriers Useful for charge balance K, Ca, Mg
Catalyst and Activators
Involved in enzyme activation and
electron transport
Fe, Mn, Zn, Cu, B, Mo,
Ni, Cl
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11. Forms of
Nutrients
Absorbed by
Plants
Nutrient
Elements
Plant Available
Forms
Nutrient
Elements
Plant Available
Forms
Nitrogen NO3
−
, NH4
+
Manganese Mn2+
Phosphorus H2PO4
−
, HPO4
2−
Zinc Zn2+
Potassium K+ Copper Cu2+
Calcium Ca2+ Boron H2BO3
−
, HBO3
2−
Magnesium Mg2+ Molybdenum MoO4
2−
Sulphur SO4
2− Chlorine Cl-
Iron Fe2+, Fe3+ Nickel Ni2+
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12. Mobility of Nutrients in Soil
Mobile Nutrients Highly soluble and not
adsorbed on clay
complexes
NO3
−
, SO4
2−
, Cl-, Mn2+
Immobile Nutrients Nutrients get fixed in the
soil
H2PO4
−
, HPO4
2−
, Zn2+
Less Mobile Nutrients Soluble but they are
adsorbed on clay complex
so the mobility is reduced
NH4
+
, K+, Ca2+, Mg2+, Cu2+
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13. Mobility of Nutrients in
Plants
Mobile Nutrients Move out of older leaves
to younger plant parts
when supplies are
inadequate
N, P, K, Cl, Mg, Mo Deficiency symptoms
first in older leaves or
lower leaves
Immobile Nutrients Cannot move from one
plant part to another
when supplies are
inadequate
B, Ca, Cu, Fe, Mn, Ni,
S, Zn
Deficiency symptoms
initially in the younger
or upper leaves
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14. Mobility of Nutrients
in Plants
N, P, K, Cl, Mg,
Mo
Mobile
Nutrients
Older
Leaves
Deficiency
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15. Mobility of Nutrients
in Plants
B, Ca, Cu, Fe,
Mn, Ni, S, Zn
Immobile
Nutrients
Younger
Leaves
Deficiency
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16. Level of
Nutrient
Elements
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17. Concentration
of Nutrients in
Dry Plant
Tissue
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18. Beneficial
Nutrients
Mineral elements which stimulate the
growth and have beneficial effects
even at very low concentration.
They are not essential or essential
only for certain plant species under
specific conditions.
Affect the uptake, translocation and
utilization of other essential nutrients.
Si, Na, Al, Co, Se, etc.
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