The document discusses the essential plant nutrients and criteria for determining nutrient essentiality. It outlines that 16 elements are considered essential for plant growth and development according to their criteria. These elements include carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, and micronutrients like boron, chlorine, copper, iron, magnesium, molybdenum, nickel, and zinc. The essential nutrients are further classified based on their amount required, mobility in soil and plants, and chemical forms absorbed by plants.

1. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
Govinda Raj Sedai
Instructor/Agriculture Coordinator
Madan Bhandari memorial Academy Nepal
School of Agriculture
Urlabari, Morang
Essential Plant Nutrients: Criteria for
Nutrient Essentiality
1
Date: 2079/01/02

2. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
2
• Dictionary meaning of nutrient is “any substances that
provides essential nourishment for the maintenance of life”.
• In other words nutrients may be defined as the chemical
compounds required by an organism for their nourishment
and maintenance of their life.
• Plants have the ability to build up organic tissues directly from
inorganic materials. They live, grow and reproduce by taking
up water and mineral substances from the soil, carbon
dioxide from the air, energy from the sun to form plant
tissues.
• By the analysis of plant tissues, there are a large number of
elements that have been identified; out of them only sixteen have
been found to be more essential for growth, development and
reproduction of plants. These essential elements are called
nutrients.
Essential Nutrients

3. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
3
• In the nature there are nearly
one hundred and three elements.
• Most of the mineral elements
present in the soil enters plants
through roots.
• Analysis of ashes of different
plants reveals that around 90
elements are taken in by the
plants
• All the 90 elements are not
present in all plants. Out of
them only 16 elements are
present (some cites 17).

4. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
4
Criteria for Nutrient Essentiality
 Daniel Arnon and Perry Stout (1939) carried out
experiment on the essentiality of nutrients in tomato.
 Laid down the basic requirements to distinguish the
elements which are essential from those which may be
taken in by the plants but are not essential
 For a plant nutrient to be essential it should fulfill the
following criteria:

5. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
5
• The element must be necessary for supporting normal
growth and reproduction. In the absence of the
element, the plants do not complete their life cycle.
• The requirements of the element must be specific and
not replaceable by another element. In other words,
deficiency of any one element cannot be met by
supplying some other element.
• The element must be directly involved in the
metabolism of the plant.
Note: Based on this, 16 elements have shown to be
generally essential to plants

6. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
6
• Chlorosis: Either the entire plant or leaf turns light green to
yellow, or appearance more localized as white or yellow
spotting.
• Necrosis: The death of plant or plant parts is observed.
• Interveinal chlorosis: Chlorosis in between the veins is
observed.
• Stunting: Plant growth is typically slow and plants are small in
nature.
• Purplish red coloring: Purplish-red discolorations in plant
stems and leaves are seen due to abnormal levels of
anthocyanin.
• Malformation of different plants occurs, example, rosette
appearance of leaves.
When there are deficiency of Essential Nutrients in
plants, following symptoms can be observed in field.

7. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
7
Classification of plant nutrients
Essential Nutrients Non-Essential/ Beneficial Nutrients
( Si, Na, I, V, Co, Ni, Se )
Macro Nutrients Micro Nutrients
( B, Fe, Zn, Cu, Cl, Mn, Mo )
Non mineral
Nutrients ( C, H, O )
Mineral
Nutrients
Primary Nutrients
( N, P, K )
Secondary Nutrients
( Ca, Mg, S )

8. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
8
Carbon (C)
Hydrogen(H)
Oxygen (O)
Nitrogen (N)
Phosphorus (P)
Potassium (K)
Calcium (Ca)
Magnesium (Mg)
Sulphur (S)
Macro
nutrients
Required by
the plants in
relatively
large
amount; >
0.1% of dry
plant tissue
Boron (B)
Iron (Fe)
Zinc (Zn)
Copper (Cu)
Chlorine (Cl)
Manganese (Mn)
Molybednum (Mo)
Micro
nutrients
Required by
the plants in
relatively less
amount; <
0.1% of dry
plant tissue
a. On the basis of amount required

9. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
9
Macronutrients are also classified as :
Carbon (C)
Hydrogen(H)
Oxygen (O)
Structural nutrients
(95-99% of fresh plant tissue)
Non-mineral nutrients
Obtained from air and water
Nitrogen (N)
Phosphorus (P)
Potassium (K)
Primary nutrients
(required in large
quantities)
Calcium (Ca)
Magnesium (Mg)
Sulphur (S)
Secondary nutrients
(required in intermediate
quantities)
Note:
• About 95-99.5% of fresh plant tissue is made up of C, H & O. only 0.5-5.0%
remains as ash after tissue is dried and burned.
• Plant growth is not seriously retarded by C, H and O as long as water is
available & CO2 in air is plentiful

10. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
Elements
Chemica
l Symbol
Atomic
weight
Ionic form absorbed by
plants
Approx. from in dry
tissue concentration
Carbon
Hydrogen
Oxygen
C
H
O
12.01
1.01
16.00
CO2
H2O
O2, H2O
40 %
6 %
40 %
Nitrogen
Phosphorus
Potassium
Magnesium
Sulfur
Calcium
N
P
K
Mg
S
Ca
14.01
30.98
39.10
24.32
32.07
40.08
NO3
-
, NH4
+
PO4
3-
, HPO4
2-
,
H2PO4
-
K+
Mg2+
SO4
2-
Ca2+
4.0 %
0.5 %
4.0 %
0.5 %
0.5 %
1.0 %
Iron
Manganese
Zinc
Copper
Boron
Molybdenum
Chlorine
Fe
Mn
Zn
Cu
B
Mo
Cl
55.85
54.94
65.38
63.54
10.82
95.95
35.46
Fe2+
, Fe3+
Mn2+
Zn2+
Cu2+
BO3
2-
, B4O7
2-
MoO4
2-
Cl-
200 ppm
200 ppm
30 ppm
10 ppm
60 ppm
2 ppm
3000 ppm

11. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
11
Beneficial nutrients:
• Helps to optimize the growth and development of plants but
they are not essential for growth.
• Essential for particular crop, but not for all crop
Eg:
Si (paddy)
Na (sugarbeet)
V (Asparagus)
I (Spinach)
Co (Grasses)
Ni (Legumes)

12. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
12
b. On the basis of mobility of nutrient in soil
i. Mobile nutrients (5)
• highly soluble, remains & moves in soil solution & these are not
adsorbed on clay complexes.
• So greater availability to plant if presents.
• But subjected to leaching along with percolating water.
• Eg. NO3
-, SO4
2-, BO3
2-, Cl-, Mn++

13. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
13
ii. Less mobile nutrients (5)
• Soluble, remains and moves along the soil solution but
are adsorbed to clay complex
• NH4
+, K+, Ca2
+, Mg2
+, Cu2
+
• Moves short distances
iii. Immobile nutrients
• Highly reactive & get fixed to the soil
• H2PO4
–, HPO4
–, Zn++
• Low plant availability;
• High application rates allow for uptake by root
interception (eg. P);

14. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
14
C. On the basis of mobility within plant
i. Mobile nutrients:
• Can translocate from older leaves to the younger leaves
when nutrient supply is reduced
• Deficiency symptoms are manifested on the older leaves.
• N, P, K, Mg, Cl, Mo
ii. Immobile nutrients:
• Cannot translocate from older leaves to the younger leaves
when nutrient supply is reduced
• Deficiency symptoms appear first on the younger leaves.
• Ca, B, Fe, Mn, Cu, Zn, S

15. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
15
Elements
Form
absorbed
Concentration
in plants
Soil pH
availability
Primary sources
Structural nutrients
Carbon(C) CO2 45% - Carbon dioxide in air
Hydrogen (H) H2o 6% - Water
Oxygen (O) CO2 , O2, H2o 43%- 45% - Water, air
Primary nutrients
Nitrogen (N) NO3
-, NH4
+ 1-6% 6-8
Organic matter,
atmosphere
Phosphorus (P) H2PO4
-, HPO4
2- 0.05-1.0%
6.5-7.5 & 8.5-
10
Soil minerals , organic
matter
Potassium (K) K+ 0.3-6% 6-10 Soil minerals
Forms of essential nutrients absorbed by plants

16. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
16
Elements
Form
absorbed
Concentration
in plants
Soil pH
availability
Primary sources
Secondary nutrients
Calcium (Ca) Ca2+ 0.1-3% 7-10 Soil minerals, limestone
Magnesium (Mg) Mg2+ 0.05-1.5% 7-10 Soil minerals, limestone
Sulfur (S)
So4
2- 0.05-1.5% 6-10
Organic matter, rain
water
Micronutrients
Iron (Fe) Fe2+, fe3+ 100-1000 Ppm Less than 6 Soil minerals
Manganese (Mn) Mn2+ 5-500 Ppm Less than 6.5 Soil minerals
Copper(Cu)
Cu2+ 2-75 Ppm 5-7
Soil minerals , organic
matter
Zinc (Zn)
Zn2+ 5-1000 Ppm 5-7
Soil minerals, organic
matter
Boron (B) H3Bo3 2-75 Ppm 5-7 Organic matter
Molybdenum
(Mo)
MoO4
2- 0.01-10 Ppm 7-10
Soil minerals, organic
matter
-

17. Essential Plant Nutrients: Criteria for Nutrient Essentiality
Madan Bhandari Memorial Academy Nepal (Affiliated to CTEVT)
Principles
and
Practices
of
Agronomy
by
Govinda
Raj
Sedai,
Agronomist
17