A. General classification
1. Major or macro-nutrients:
Those nutrients which are required by the plants in concentrations more than 1 ppm are termed as major or macro-nutrients.
These are grouped in to:-
A. Basic nutrients: C, H, O Provides basic structure to plants.
B. Primary nutrient: N, P, K
C. Secondary: Ca, Mg, S
2. Minor or micro-nutrients:
. The elements which are required by plants in concentration less than 1 ppm are put in this category.
. They are also called as trace elements or oligo elements. These are Fe, Mn, Zn, Cu, Bo, Cl and Molybdenum
3. Immobile nutrients:
Ca& B
4. Energy exchange: H & O
5. Cation nutrients:
K, Ca, Mg, Fe, Mn, Cu, Zn
6. Anion mitrients:
P, B, Mo, Cl, So4
7. Both anion &cation form:
N (NH4+, NO3)
8. Nonmetals nutrients: B
B. Other classification of plant nutrients
- Essential nutrient:
According to Arnon & Stout there are 16 essential nutrients for plants e.g. C, H,O, NPK, Ca, Mg, S, Fe, Mn, Mo, B, Zn, Cu, Cl.
Nickel is the 17 essential element known in 1987 by Brown et al.