There are 16 elements identified which are essential for plant growth and completion of life cycle. These 16 elements are not required for all plants, but all have been found essential for one plant or the other.
Depending on the quantity of nutrients present in plants, they can be grouped into three
- Basic Nutrients
- Macro Nutrients
- Micro Nutrients
Basic Nutrients: The basic nutrients viz. Carbon, Hydrogen and Oxygen constitute 96 % of total dry matter of plants.
Macro Nutrients: Those elements which are required in large quantities are known as macro nutrients namely:
- Nitrogen (N)
- Phosphorus(P)
- Potassium (K)
- Calcium (Ca)
- Magnesium (Mg)
- Sulphur (S)
Primary Nutrients: Those macro nutrients which are used up in maximum quantity for plant growth & development. N, P and K are categorized as primary nutrients. Most frequently required to improve soil fertility.
Nitrogen
- Necessary for formation of the building blocks of protein called amino acid
- Vital for proper plant growth
- Directly involved in photosynthesis process & production of carbohydrates
- Key component of vitamins
- Affects energy reactions in the plant
Phosphorus
- Promotes early root formation and growth
- Facilitates energy storage and transfer
- Improves quality of fruits, vegetables, and grains
- Helps plants survive harsh winter conditions
- Improves water-use efficiency
Potassium
- Carbohydrate metabolism and the break down and translocation of starches
- Activates enzymes and controls their reaction rates
- Improves quality of seeds and fruit
- Improves winter hardiness
- Increases disease resistance of plants
Secondary Nutrients: Ca, Mg and S are categorized as secondary nutrients. For most crops, these three macronutrients are needed comparatively in lesser amount than the primary nutrients.
Calcium
- Utilized for Continuous cell formation
- Increases fruit set
- Essential for nut development in peanuts
- Stimulates microbial activity
Magnesium
- Key element of chlorophyll production
- Activator and component of many plant enzymes
- Increases iron utilization in plants
- Influences uniformity of plant maturity
Sulphur
- Integral part of amino acids/proteins
- Helps to develop enzymes and vitamins
- Promotes nodule formation on legumes
- Aids in seed production
- Plays a vital role in chlorophyll formation (though it isn’t one of the constituents)