Transcript micronutrient

Role
and
deficiency
micronutrients in Mango
symptoms
of
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
Hence, it is important to have
the economic yield of the tree.
proper knowledge to identifying
deficiency/toxicity symptoms of
these micronutrients for timely
correction.
Objective
After completing this lesson, you will be able to :
Explain the role, deficiency symptoms and
symptoms of excess of micronutrients in
mango
Role of copper
It is a component of
plaxtocyanin which plays
a role in protein and
carbohydrates synthesis.
Cu is part of the
chloroplast protein
plastocyanin, which forms
part of the electron
transport chain.
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.
Role of iron
Constituent of
cytochrome for
respiration. It bring
about chlorophyll
formation an electron
transport.
Fe is part of protein
ferredoxin and is
required in nitrate and
sulfate reductions.
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.
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.
Role of boron
It helps in cell division
and cell differentiation.
Role of Molybdenum
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.
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.
On the branches, Cu
deficiency causes boillike eruptions on the
bark that, at times,
weeps sap.
Copper deficiency in
mango orchards caused
long, tender and
“S”shaped 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
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.
Causes of iron deficiency
Iron deficiency is
associated with soils
derived from calcareous
material or acidic soils
with very high levels of
manganese (Mn).
Associated with an excess
of Mn applying large
amounts of P fertilizer may
also induce Fe deficiency
in mango.
Sometimes excessive
amounts of Mn in poorly
drained soils can induce Fe
deficiency in plants.
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 tuftshaped secondary branches.
Internal necrosis
Deficiency symptoms of boron
The floral panicles are
smaller and have fewer
hermaphroditic flowers.
Boron deficiency caused
physiological disorder
known as internal necrosis
and symptoms starts from
browning of seed and
measocarp tissues.
Internal necrosis
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.
Deficiency symptoms of manganese
In severe deficiency, the new
leaves become chlorotic, with
necrosis along the extremities
of the lamina.
Liming and the application of
large amounts of P decrease
the availability of manganese
in the soil.
Due to manganese
deficiency mottling of leaves
followed by complete
yellowing with dark brown pin
head like spot scattered all
over the laminae.
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.