Mineral nutrients play essential roles in plant growth and function. They can be classified as macronutrients, which are needed in large quantities, or micronutrients, which are needed in small amounts. Macronutrients include nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. Micronutrients include iron, manganese, zinc, copper, molybdenum, chlorine, and boron. Each mineral nutrient serves specific functions, such as components of proteins, chlorophyll, enzymes, cell walls, and in biochemical processes like photosynthesis and respiration. Deficiency of different minerals leads to distinct symptoms that vary depending on the mobility of the nutrient within the plant.

1. ENVIRONMENTAL SCIENCE
Dr. Thirunahari Ugandhar
Head & Assistant Professor in Botany
Dr. Thirunahari Ugandhar
Head & Assistant Professor of Botany

2. SUBTOPICS
Mineral nutrition important
Classification of minerals
Roles and properties 0f
minerals Deficiency symptoms
0f minerals

4. Why Is Mineral Nutrition Important?
 In most natural soils, the
availability of mineral nutrients
limits plant growth and primary
productivity.
 Nutrient limitation is an important
selective pressure and plants face
many special changes related to
the need to acquire and use
mineral nutrients efficiently.
 “Plant nutrition” specifically does not
refer to photosynthesis.

5. Classification Of Minerals:
 On the basis of the amounts found in
plants:
 Macronutrients: N, K, Ca, Mg, P, S, Na,
(Si)
 Micronutrients: Cl, Fe, B, Mn, Zn, Cu, Mo,
Ni

6. Essential Elements :
What defines an “essential” element?
1. In its absence the plant cannot complete a normal life
cycle
2. The element is part of an essential
molecule (macromolecule, metabolite)
inside the plant
 Most elements fall into both categories above (e.g.,
structural vs. enzyme cofactor)
 These 17 elements are classified as
 9 macronutrients (present at > 10 mmol / kg dry wt.)

7.  Hydroponic culture can determine which mineral elements
are actually essential nutrients.
Essential Elements :

8. Classification of
minerals:
 Macronutrients are elements required by plants
in relatively large quantities (9 total).
 Organic compounds: Carbon, oxygen, hydrogen,
nitrogen, sulfur, and phosphorus.
 The other three are potassium, calcium, and
magnesium.

9.  Micronutrients elements are nutrients that the
plants need in very small amounts (8 total).
 Iron, chlorine, copper, zinc, manganese,
molybdenum, boron, and nickel.
 Most function as cofactors of enzymatic reactions.
Classification of
minerals:

14. Name Function in plant
Chemical
symbol
Relative
% in plant
to N
Primary macronutrients
Nitrogen N 100 Proteins, amino acids
Phosphorus P 6 Nucleic acids, ATP
Potassium K 25 Catalyst, ion transport
Secondary macronutrients
Calcium Ca 12.5 Cell wall component
Magnesium Mg 8 Part of chlorophyll
Sulfur S 3 Amino acids
Iron Fe 0.2 Chlorophyll synthesis
Micronutrients
Copper Cu 0.01 Component of enzymes
Manganese Mn 0.1 Activates enzymes
Zinc Zn 0.03 Activates enzymes
Boron B 0.2 Cell wall component
Molybdenum Mo 0.0001 Involved in N fixation
Chlorine Cl 0.3 Photosynthesis reactions

17. ROLES, PROPERTIES AND
DEFICIEN
CY SYMPTOMS OF MINERALS

18. CARBON (C):
Roles and properties:
 Basic structural element of life.
 Although not very plentiful in the earth's crust
(<0.1%), carbon is one of the most abundant
elements in living things.
 It occurs in plants combined with hydrogen and
oxygen in the form of hydrocarbons., and in their
geological derivatives, petroleum and coal.
 Carbon also occurs in the atmosphere as CO2,
and in rocks as carbonate minerals such as
limestone.
Deficiency symptoms:
 Very serious, no growth!

19. OXYGEN (O):
Roles and properties:
 Powerful oxidizing agent .
 Oxygen is the most abundant element in the earths
crust on the basis of both mass and number of atoms
(49.5% of the mass of the earths crust is oxygen
atoms).
 In the free state oxygen occurs in the atmosphere as
O2 molecules (21% of air by mass).
 In the combined state, oxygen occurs in many
minerals, living things and water.
Deficiency symptoms:
 No Respiration.

20. HYDROGEN (H):
Roles and properties:
 Lightest element, and a powerful reducing agent.
 Most abundant element in the universe.
 In the earth's crust hydrogen is third in abundance on an
atom basis. On a mass basis, it is ninth in order of
abundance .
 Free, uncombined hydrogen is very rare.
 However, combined hydrogen is quite common (eg.,
water,
and organic compounds).
 Supplied in the mobile oxidized form of H2O, and made
available as a reducing element by photosynthesis.
 Forms covalent bonds with the electronegative elements C,
N, O and H. Pretty important for hydrogen bonding!

21. NITROGEN (N):
Roles and properties:
 About 1/3 as abundant as carbon. Occurs principally as
diatomic N2 in the atmosphere.
 Makes + charged groups
possible.
 Amine N is important in complexing metals (eg., binding
Fe in cytochromes, or binding Mg in chlorophyll).
 Acts as a donor atom in many enzymatically
catalyzed reactions.
 In living things, N is found almost exclusively in the fully
reduced state.
 Most of the N absorbed from the soil by higher plants is in
the fully oxidized form of NO3, and must be reduced for

22. NITROGEN (N):
Deficiency symptoms:
 General chlorosis,especially of older
leaves (mobile).
 In severe cases these leaves yellow and
die.
 Younger leaves remain green longer,
because they receive soluble forms
of nitrogen transported from older
leaves.
 In many plants, excess nitrogen often
stimulates shoot growth more than root
growth and may favor vegetative growth
over flowering and seed formation.

23. PHOSPHOROUS (P):
Roles and properties:
 Occurs and reacts as orthophosphate, the fully oxidized
and stable form.
 Participates in metabolism by forming water-stable
phosphate esters and anhydrides. In these forms P has
several fundamental roles:
 Linkage (as in nucleic acids),
 Source of free energy in bond formation (Carries
chemical energy in ATP).
 Component of sugar-phosphates; (in DNA & RNA)
 Component of phopholipids (in membranes)
 Mg++ (or Mn++) is a required cofactor in reactions
involving phosphate transfer. Mg++ also commonly
neutralizes polyphosphate compounds.

24. PHOSPHOROUS (P):
Deficiency symptoms:
 Phosphorous-deficient plants are
stunted (stop growth) and , in contrast
to those lacking nitrogen, are often
dark green.
 Phosphate is easily redistributed
(mobile) in most plants from one organ
to another and is lost from older
leaves, accumulating in younger
leaves, developing flowers and seeds.
As a result, deficiency symptoms
occur first in more mature leaves.

25. SULFUR (S):
Roles and properties:
 Occurs primarily in reduced form in living things.
 Disulfides are more stable than dioxides (or peroxides),
permitting -SH participation in redox reactions (-SH + HS- --
-- -S- S-).
 SH groups are also form hydrogen bonds.
 SH groups can be the reactive sites of enzymes or
coenzymes (Coenzyme A) and are important for
protein conformation.
 Sulfate (SO4=) from the soil is the primary source of S,
although some SO2 is absorbed from the atmosphere (too
much SO2 can be quite toxic to plants.
 Sulfate reduction is very energy intensive and occurs mainly

26. SULFUR (S):
Deficiency symptoms:
 General chlorosis of leaf, including
vascular bundles.
 Sulfur is not easily redistributed
(immobile) from mature tissues in
some species, so deficiencies are
usually noted first in younger
leaves.

27. POTASSIUM (K+):
Roles and properties:
 Dominant cation in plants.
 K+ is an activator of many enzymes that are essential
for photosynthesis and respiration, and it also
activates enzymes needed to form starch and
proteins.
 K+ is quite mobile in the plant, because there are
many membrane carrier systems adapted to K+.
 It is a major contributor to the osmotic potential of cells
and therefore to their turgor pressure.
 K+ regulation of osmotic potentials forms the basis
for turgor movements in plants (eg., stomate
opening, leaf movements).

28. POTASSIUM (K+):
Deficiency symptoms:
 As with N and P, K+ is easily
redistributed (mobile) from
mature to younger organs, so
symptoms first appear in older
leaves.
 Leaves develop necrotic
lesions and light chlorosis.
 The tips often die first.
 K+ deficient cereals develop
weak stems so they are easily
fall.

29. CALCIUM (CA++):
Roles and properties:
 Often the most abundant divalent cation in plants.
 Important component of cell walls.
 It stabilizes the polysaccharides by forming
intermolecular complexes with -COO- groups of
pectins.
 Calcium is also important for maintaining the safety of
membranes, especially the plasma membrane.
 Free calcium concentration in the cytosol is normally very
low, about 10-7 M. Some hormonal or environmental
signals raise the free Ca++ concentration to 10-6 to 10-5
M.
 Because changes in calcium are associated with hormonal

30. CALCIUM (CA++):
Deficiency symptoms:
 Meristematic regions die.
 Margins of younger leaves
become chlorotic then
necrotic.
 Young leaves are distorted.
 Symptoms appear first in
young tissues since Ca++ is
not very mobile.

31. MAGNESIUM (MG++):
Roles and properties:
 Most important divalent cation in enzymatic catalysis.
 Involved in most reactions involving ADP and ATP.
 Activates enzymes for DNA and RNA synthesis.
 Constituent of chlorophyll.
 Activates key enzymes involved in CO2 fixation.
 Has structural roles in membranes, especially in
organelles.

32. MAGNESIUM (MG++):
Deficiency
symptoms:
 Deficiency causes extensive
interveinal chlorosis which
starts with basal leaves
(older) and progresses to
younger leaves (mobile).

33. IRON (Fe++):
Roles and properties:
 Important for its oxidation-reduction properties (Fe+++
to Fe++).
 Iron forms a locus for electron transfer in many
enzymes (eg., cytochromes, peroxidases,
catalyses).
 It is also required for chlorophyll synthesis.
 Iron is a difficult cation for plants to handle since it
readily precipitates.

34. IRON (FE++):
Deficiency symptoms:
 Extensive interveinal chlorosis, starting with younger
leaves (iron is relatively immobile).
 Similar to Mg deficiency except in younger leaves.

35. COPPER (CU++):
Roles and properties:
 Important for its oxidation-reduction properties
(Cu++ to Cu+)
 Copper is an important component of several
critical enzymes (eg., plastocyanin for
photosynthesis and cytochrome oxidase for
respiration).

36. COPPER (CU++):
Deficiency symptoms:
 Plants need very little copper so they are rarely deficient in
it
(usually sufficiently available in soil).
 Experimentally, copper deficiency leads to distorted and
dark green younger leaves. (immobile)

37. MOLYBDENUM (MO6+):
Roles and properties:
 Important for its oxidation-reduction properties.
 It is a key component of nitrate reductase where
it functions as an e- carrier for nitrate
reduction.
 It is also important in organisms that can carry
out nitrogen fixation (from N2).

38. MOLYBDENUM (MO6+):
Deficiency symptoms:
 Most plants require less
molybdenum than any other
element, so deficiencies are
rare.
 Symptoms often consist of
interveinal chlorosis, first in
older leaves. (mobile)
 Young leaves may be severely
twisted (whiptail disease).

39. MANGANESE (MN++):
Roles and properties:
 Important for its oxidation-reduction properties.
 A major role for manganese is in the removal of
electrons from water during photosynthesis
(wate
r oxidation).
 Manganese also is essential in respiration
and nitrogen metabolism.
 It can function effectively in some metal
catalyzed enzymatic reactions which require
magnesium.

40. MANGANESE (MN++):
Deficiency symptoms:
 However, deficiencies are rare
since low amounts are required
and it is usually in plentiful supply
in soil.
 The absence of Manganese
causes disorganization of
chloroplast thylakoid
membranes.
 Plants become chlorotic.

41. ZINC (ZN++):
Roles and properties:
 Important in enzymes with
oxidation-reduction
properties.
Deficiency symptoms:
 Interveinal chlorosis and
inhibition of stem
growth.
 Leaf margins are distorted
and puckered.

42. BORON (B(OH)3):
Roles and properties:
 Specific function unknown. However, boron
is found in cell walls complexed with
raffinose- containing polymers.
 It is also found in phloem complexed
with sorbitol.
 pollen tubes can't elongate without boron.
 Some research suggests a role for
boron during synthesis of nucleic
acids.
Deficiency symptoms:
 Several disorders related to disintegration of
internal tissues such as "heart rot" of beets
and "stem crack" of celery .

43. CHLORIDE (CL-):
Roles and properties:
 Plants frequently contain a good
deal of chloride but very little is
required as a nutrient.
 It has important functions
in photosynthesis.
 It may play a general role in
maintaining electrical
equilibrium.
Deficiency symptoms:
 The leaves have abnormal
shapes, with distinct interveinal
chlorosis.

44. ROLES AND PROPERTIES:
Sodium (Na+):
 Essential for some halophytes.
 Sodium can replace potassium where it is deficient.
 Exact functions unknown. May be important for
maintaining electrical equilibrium.
Silicon (Si4+):
 Abundant in soils. Absorbed from soils as silicic acid
(H4SiO4).
 Is used by some plants to strengthen cell walls (eg., rice,
oats, equisetum).
Cobalt:
 Not required by plants, but required by the bacteroids of

45. Element Function
C,H,O Throughout the plant, organic compounds,
sugars, cellulose, starch, lipids, . . .
N Component of amino acids (required for
protein synthesis), nucleic acids (DNA,
RNA), chlorophyll
K Regulates osmotic balance, especially in stomatal
Opening/closing; enzyme activator
Ca Major component of the cell wall; enzyme
cofactor; component of calmodulin (signal
transduction component); mediates membrane
permeability
P Carries chemical energy in ATP, sugar-
phosphates; component of DNA & RNA;
A summary of the functions of inorganic
nutrients in plants.

46. Element Function
Mg Cofactor of chlorophyll; enzyme activator
S Component of 2 amino acids (forms disulfide
bonds in proteins); cofactor of enzymes (coa)
Fe Cofactor of cytochromes (electron transfer proteins);
required for chlorophyll synthesis
Cl Regulates osmotic balance; component
of photosynthetic reaction center (PSII)
Cu Cofactor of photosynthetic electron transfer
protein (Plastocyanin), respriratory electron
transfer protein (Cytochrome c oxidase) and of
other enzymes
A summary of the functions of inorganic
nutrients in plants.

47. Element Function
Mn Component of photosynthetic reaction center (PSII);
cofactor of some enzymes
Zn Enzyme cofactor
Mo Required for nitrogen fixation and nitrate (NO3
-) Reduction
B Mediates ca utilization, nucleic acid synthesis,
and lignin synthesis
Ni Constituent of the enzyme urease
Na Regulates osmotic balance in some plants;
required for C4 photosynthesis
Si Cell wall structural element in rice & equisetum
A summary of the functions of inorganic
nutrients in plants.

48. Element Deficiency symptoms
Symptoms in older leaves first
N Stunted growth; pale green, yellow, or brown
leaves; slender stems; anthocyanin
accumulation
K Mottled or chlorotic leaves (faded green/yellow)
with dead spots (necrosis); curling or crinkling
P Stunted growth, dark green leaves with dead
spots (necrosis); some anthocyanin
accumulation
Mg Mottled or chlorotic leaves (interveinal); tips
& edges of leaves curl upward
Common mineral deficiency symptoms
observed in plants.

49. Elemen
t
Deficiency symptoms
Symptoms in younger leaves first
Ca Young leaves at bud hooked, then die back
at edges, stalk dies at bud
B Young leaves of the terminal bud light green,
leaves twisted, stalk dies at bud
S Chlorosis, young leaves light green;
some anthocyanin accumulation
Fe Young leaves chlorotic (interveinal)
Cu Young leaves wilted, wilted terminal bud,
dark green leavesw/necrosis
Common mineral deficiency symptoms
observed in plants.

50. Element Deficiency symptoms
Symptoms in younger leaves first
Mn Chlorosis (interveinal), necrosis
Zn Rosette growth, leaves small, puckered
(makes less auxin)
Mo Interveinal chlorosis, necrosis; poor
flowering; can cause N deficiency
Cl Wilting at leaf tips; general chlorosis &
necrosis,
bronzing, stunted
Common mineral deficiency symptoms
observed in plants.