A pictorial description of functions and deficiency symptoms of Zn, Mo, Cl, and Ni in plants.

1. Soil Fertility
Management
Mr. Aditya Kumar Verma
1

2. Topics for Discussion!
• Functions and Deficiency Symptoms of:
• Zinc
• Molybdenum
• Chlorine
• Nickel
2

3. Zinc
(Zn2+)
Functions of Zinc in Plants:
• Zinc is involved in number of enzymatic
reactions.
• It plays an important role in the synthesis of
tryptophan which is the constituent of some
proteins. Tryptophan is also the precursor of
plant growth hormones such as IAA.
• It is also involved in chlorophyll synthesis.
• Zinc plays an important role in cell membrane
integrity.
Concentration in
Mature Leaf Tissue:
27 - 150 mg/kg
3

4. Zinc
(Zn2+)
Deficiency:
Younger Leaves
• Interveinal chlorosis
• Reduction in size of young leaves which are
often clustered or borne very closely.
• Bronzing, purple, violet, reddish-brown or
brown coloration of foliage.
• Shortening of stem or stalk internodes and
malformation of fruit.
Deficiency Symptoms
4

5. Zinc
(Zn2+)
Deficiency:
Younger Leaves
• Mottle leaf (little-leaf type) of citrus
• White bud of maize
• Khaira disease of rice
Deficiency Symptoms
5

6. Zinc
(Zn2+)
Deficiency:
Younger Leaves
6
Mottle Leaf of Citrus
Young leaves show chlorotic mottling in the interveinal areas.
Rosetting or clustering of small leaves at the top of the shoots.

7. Zinc
(Zn2+)
Deficiency:
Younger Leaves
7
White Bud of Maize
Interveinal areas become light yellow and develop
white necrotic spots that later develop dark brown necrotic areas.

8. Zinc
(Zn2+)
Deficiency:
Younger Leaves
8
White Bud of Maize
Interveinal areas become light yellow and develop
white necrotic spots that later develop dark brown necrotic areas.

9. Zinc
(Zn2+)
Deficiency:
Younger Leaves
9
Khaira Disease of Rice
Reddish brown pigmentation of young leaves
of 3-4 weeks old seedlings.

10. Zinc
(Zn2+)
Deficiency:
Younger Leaves
10
Khaira Disease of Rice
Reddish brown pigmentation of young leaves
of 3-4 weeks old seedlings.

11. Molybdenum
(MoO4
2−
)
Functions of Molybdenum in Plants:
• It is an essential component of nitrate
reductase responsible for conversion of nitrate
to nitrite during nitrogen assimilation.
• It is a structural component of enzyme
nitrogenase essential for nitrogen fixation.
• It is involved in carbohydrate and phosphate
metabolism.
• It has an essential role in iron absorption and
translocation in plants.
Concentration in
Mature Leaf Tissue:
0.1 – 2.0 mg/kg
11

12. Molybdenum
(MoO4
2−
)
Deficiency:
Older Leaves
• Reddish or purple discoloration of leaves,
chlorosis and marginal necrosis of leaves.
• Marginal scorching and rolling or cupping of
leaves.
• Yellow spot disease of citrus.
• Whiptail of cauliflower.
Deficiency Symptoms
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13. Molybdenum
(MoO4
2−
)
Deficiency:
Older Leaves
13

14. Molybdenum
(MoO4
2−
)
Deficiency:
Older Leaves
14

15. Molybdenum
(MoO4
2−
)
Deficiency:
Older Leaves
15
Yellow Spot Disease of Citrus

16. Molybdenum
(MoO4
2−
)
Deficiency:
Older Leaves
16
Whiptail of Cauliflower

17. Chlorine
(Cl-)
Functions of Chlorine in Plants:
• It plays a major role in osmoregulation (cell
elongation, stomatal opening) and charge
compensation in higher plants.
• It acts as a co-factor in Mn-containing water
splitting enzyme of photosystem-II.
Concentration in
Mature Leaf Tissue:
100 – 500 mg/kg
17

18. Chlorine
(Cl-)
Deficiency:
Older Leaves
• Chlorosis and burning of tips and margin of
leaves.
• In tomato, leaves becomes chlorotic and
later bronzed.
• Over wilting effect and leaf fall, yielding
ability decreases.
Deficiency Symptoms
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19. Chlorine
(Cl-)
Deficiency:
Older Leaves
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20. Chlorine
(Cl-)
Deficiency:
Older Leaves
20

21. Nickel
(Ni2+)
Functions of Nickel in Plants:
• Nickel is associated with nitrogen metabolism
by way of influencing urease activity.
• In systems where urea is used as the sole N
fertilizer for foliar spray and Ni supply is poor,
lower urease activity causes urea toxicity to the
foliage and leads to severe necrosis of root tips.
• It facilitates transport of nutrients to the seeds
or grains.
• It is essential for hydrogenase activity
necessary for nitrogen fixation by rhizobia in
legumes.
Concentration in
Mature Leaf Tissue:
0.1 – 10 mg/kg
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22. Nickel
(Ni2+)
Deficiency:
Younger Leaves
• Characteristic visual deficiency symptoms of
Ni have so far not been adequately defined.
• Reduction in grain yield of cereals,
accumulation of nitrate and thereby
decrease in protein content.
• Chlorosis in youngest leaves that progresses
to necrosis.
Deficiency Symptoms
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23. Nickel
(Ni2+)
Deficiency:
Younger Leaves
23

24. Nickel
(Ni2+)
Deficiency:
Younger Leaves
24

25. Nickel
(Ni2+)
Deficiency:
Younger Leaves
25