Integrated%20nutrient%20management%20in%20mango

1
Role and deficiency symptoms of micronutrients in
Mango

Micronutrients are equally important as macro
nutrients require for proper growth of mango
tree. The requirement of micronutrients are only
traces which is partly met from the soils or
through chemical fertilizers or through some
other sources. Mango trees suffer widely by the
deficiency of micronutrients. If these are
corrected at proper time, it definitely boosts up
the economic yield of the tree.
Hence, it is important to have proper knowledge
to identifying deficiency/toxicity symptoms of
these micronutrients for timely correction.
2

Objective

• After completing this lesson, you will be able to
  
• Explain the role, deficiency symptoms and
  symptoms of excess of micronutrients in mango

3
Role of copper
It is a component of plaxtocyanin which plays a
role in protein and carbohydrates synthesis.

Cu is essential in several plant enzyme systems
involved in photosynthesis.
Cu may have a role in the synthesis and/or
stability of chlorophyll and other plant
pigments.
Cu is part of the chloroplast protein
plastocyanin, which forms part of the electron
transport chain.
4
Role of iron
Constituent of cytochrome for respiration. It
bring about chlorophyll formation an electron
transport.

Fe is essential in the heme enzyme system in
plant metabolism (photosynthesis and
respiration). The enzymes involved include
catalase, peroxidase, cytochrome oxidase, and
other cytochromes.
Fe is essential in the synthesis and maintenance
of chlorophyll in plants and strongly associated
with protein metabolism.
Fe is part of protein ferredoxin and is required
in nitrate and sulfate reductions.
5
Role of Manganese
Activator of enzymes in photosynthesis. Essential
for chlorophyll formation.
Mn is involved in the oxidation-reduction process
in photosynthesis.
Role of Zinc
Activator of enzymes in respiration. It has role
in protein synthesis. Essential for auxin
synthesis.
Zn is required in the synthesis of tryptophan,
which in turn is necessary for the formation of
indole acetic acid in plants.
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Role of boron
It helps in cell division and cell
differentiation.

Role of Molybdenum
Zn is required in the synthesis of tryptophan,
which in turn is necessary for the formation of
indole acetic acid in plants.
Activator of enzymes in respiration. It has role
in protein synthesis. Essential for auxin
synthesis.
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Deficiency symptoms of copper
Copper deficiency are seen frequently in young
plants getting large amounts of N, or in the
young shoots of adult plants.
Copper deficiency in mango orchards caused long,
tender and Sshaped branches and leaves with
downward curls, both on the lamina and the
central vein.

Progressive terminal branch death may occur under
where new shoots were curved or S-shaped in the
previous year
On the branches, Cu deficiency causes boil-like
eruptions on the bark that, at times, weeps sap.
8
Deficiency symptoms of iron
Iron deficiency is manifest by typical chlorosis
in new leaves, which have a mesh of green veins
contrasting with the yellow of the lamina.

In situations of acute deficiency branches and
twigs may die.
Young leaves are always affected first.
Severely affected leaves may be pale yellow, with
little or no green in the veins.
9
Causes of iron deficiency
Iron deficiency is associated with soils derived
from calcareous material or acidic soils with
very high levels of manganese (Mn).

Sometimes excessive amounts of Mn in poorly
drained soils can induce Fe deficiency in plants.
Associated with an excess of Mn applying large
amounts of P fertilizer may also induce Fe
deficiency in mango.
10
Deficiency symptoms of boron

Boron deficiency first occur in the youngest
parts of the plant, while its toxicity is seen at
the extremities of the oldest leaves.
Boron deficiency causes death of the apical bud,
which results in an excessive number of lateral
buds that develop tuft-shaped secondary branches.
Internal necrosis
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Deficiency symptoms of boron

The floral panicles are smaller and have fewer
hermaphroditic flowers.
Internal necrosis
Boron deficiency caused physiological disorder
known as internal necrosis and symptoms starts
from browning of seed and measocarp tissues.
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Deficiency symptoms of manganese
Manganese deficiency causes reduced growth,
similar to deficiencies of P and Mg.

New leaves have a yellowish green lamina, with a
noticeable green mesh between the veins, which
are thicker than those associated with Fe
deficiency.
The first symptoms appear on new leaves, which
have a yellowish green background.
13
Deficiency symptoms of manganese

In severe deficiency, the new leaves become
chlorotic, with necrosis along the extremities of
the lamina.
Due to manganese deficiency mottling of leaves
followed by complete yellowing with dark brown
pin head like spot scattered all over the laminae.
Liming and the application of large amounts of P
decrease the availability of manganese in the
soil.
14
Deficiency symptoms of Zinc

Zinc deficiency markedly reduced the leaf size
and inhibited plant growth appreciably.
Zinc deficiency found to be the cause of severe
malformation in mature mango trees.