Arnon's Criteria for Plant Nutrient Essentiality, Deficiency and toxicity symptoms of Nutrients

1. Dr.AB Jadhav, SSAC,AC, Pune
• Soil as a Source of Plant Nutrient
• Criteria of Essentiality (Arnon 1954)
• Forms of Nutrient in Soil
• Essential and Beneficial Nutrients and their
Role / function
Dr. Anand B. Jadhav
Assistant Professor of SSAC
College of Agriculture, Pune

2. In the 19th century, the German scientist Justus von
Liebig formulated the “Law of the Minimum,” which states
that if one of the essential plant nutrients is
deficient, plant growth will be poor even when all other
essential nutrients are abundant.

3. Criteria of Essentiality
Proposed by Arnon and Stout (1939)
Modified by Arnon (1957)
The plant must be unable to grow normally or
complete its life cycle in the absence of the element.
The element is specific and cannot be replaced
by another
The element plays a direct role in metabolism.
1)
2)
3)

6. Essential
Nutrient
• A nutrient required for normal growth plant and
without which plant can not complete its life
cycle
Beneficial
Nutrient
• Mineral element which either stimulate growth
but are not essential or which are essential for
certain plant species or under given conditions
• It is that part of Nutrient which is
actual available to plant and
whose variation in soil affects the
response of crop in terms of yield
Available
Nutrient

7. • When concentration of an essential nutrient is low
enough to severely limit yield and distinct
deficiency symptoms are visible
Deficient
• The nutrient concentration range in which added
nutrient will not increase yield but can increase
nutrient concentration
Critical range
Steenberg
effect
• Yield is severely affected when a nutrient is deficient
and when the nutrient deficiency is corrected, growth
increases more rapidly than nutrient concentration or
• Under severe deficiency, rapid increase in yield with
added nutrient can cause a small decrease in nutrient
concentration this effect is called

8. MAJOR
Carbon, Hydrogen,
Oxygen, Nitrogen,
Phosphorus &
potassium
potassium
SECONDARY
Calcium, Magnesium
& Sulphur
MICRONUTRIENTS
Iron, Manganese, Zinc,
Cupper, Boron,
Molybdenum &
Chlorine
Essential Nutrients

10. Dr.AB Jadhav, SSAC,AC, Pune
Essential Nutrients for Plants
Chemical AtomicIonic forms Approximate dry
Element symbol weightAbsorbed by plants ____ concentration_____
Mccronutrients
Nitrogen N 14.01 NO3
-, NH4
+ 4.0 %
Phosphorus P 30.98 PO4
3-, HPO4
2-, H2PO4
- 0.5 %
Potassium K 39.10 K+ 4.0 %
Magnesium Mg 24.32 Mg2+ 0.5 %
Sulfur S 32.07 SO4
2- 0.5 %
Calcium Ca 40.08 Ca2+ 1.0 %
Micronutrients
Iron Fe 55.85 Fe2+, Fe3+ 200 ppm
Manganese Mn 54.94 Mn2+ 200 ppm
Zinc Zn 65.38 Zn2+ 30 ppm
Copper Cu 63.54 Cu2
+ 10 ppm
Boron B 10.82 BO3
2-, B4O7
2- 60 ppm
Molybdenum Mo 95.95 MoO4
2- 2 ppm
Chlorine Cl 35.46 Cl- 3000 ppm
Essential But Not Applied
Carbon C 12.01 CO2 40 %
Hydrogen H 1.01 H2O 6 %
Oxygen O 16.00 O2, H2O 40 %
________________________________________________________________
Plant tissues also contain other elements (Na, Se, Co, Si, Rb, Sr, F, I) which are not needed for the normal growth
and development.

11. Plant Soil
Mobile Immobile Mobile Immobile
N B H3BO3, H2BO3 NH4
P Ca NO3 Ca2+ and Mg2+
K Cu SO4 Cu2+
Mg Fe Cl Fe2+ and Fe3+
Cl Mn MoO4
Mo Zn H2PO4, HPO4
S K+
Mobility of Nutrients in Plant and Soil
Cations Anions Metals Non-metals
K, Ca and Mg NO3, H2PO4
and SO4
K, Ca and Mg
Fe, Mn, Zn and Cu
N, P, S B,
MO and Cl
Fe, Mn, Zn and Cu

12. Dr.AB Jadhav, SSAC,AC, Pune
Plant Nutrient Deficiency Terminology
Burning
Severe localized yellowing; scorched
appearance.
Generalized
Symptoms not limited to one area of a
plant, but rather spread over the entire
plant.
Chlorosis
General yellowing of the plant tissue;
lack of chlorophyll.
Necrosis
Death of plant tissue; tissue browns
and dies.
Mobile
Able to be moved from one plant part
to another.
Immobile
Not able to be moved from one part of
the plant to another.
Interveinal Chlorosis
Yellowing in between leaf veins, yet
veins remain green.
Mottling
Spotted, irregular, inconsistent
pattern.
Localized
Symptoms limited to one leaf or one
section of the leaf or plant.
Stunting
Decreased growth; shorter height of
the affected plants

17. NITROGEN
Role or
Function
Component of chlorophyll, enzyme, amino acids and protein
Encourages vegetative growth & deep green colour
Enhances plumpness in cereal crops and succulence in crops
Role in utilization of carbohydrates
Deficiency
symptoms
General chlorosis of lower leaves (light green to yellow), stunted and
slow growth, and necrosis of older leaves in severe cases
In cereals, yellow discoloration from the leaf tip backward in the form
of a “V” is common
Stunted growth/Less vegetative
Roots are unable to absorb sufficient N- proteins in the older part get
converted & translocated towards top part
Toxicity
symptoms
Higher photosynthetic rate & vigorous vegetative growth
Succulence & dark green colour causes disease/ pest succeptibiltiy
Delays crop maturity, weakening of fiber, lodging of crops
Excess N enhances loss of soil moisture

18. Barley
Cucumber
Corn
Nitrogen
Citrus
Soybean

19. PHOSPHORUS
Role or
Function
Energy storage & transfer (1 ATP/ADP= 1200 cal/mole)
Cell division, cell development, root lengthening, seed and fruit
development, early maturity and early ripening
Component of nucleic acid, co-enzyme, nucleotides, phospholipids,
phosphoproteins & sugar phosphates
Phytic acid/ phytin- storage form of P in seeds
Deficiency
symptoms
Older leaves are affected first and acquire a purplish discoloration due
to the accumulation of sugars in P deficient plants which favor
anthocyanin synthesis;
Deficiency first appears on older leaves, retard plant growth, shoot
growth is depressed, potato tuber develops rusty lessions
Decrease in number of flowers & delays flower initiation & poor earhead
formation
Dark green leaves (Chlorophyll is high but photosynthetic rate less)
Toxicity Higher P plant have Zn deficiency and Chlorosis

20. Stunted with dark green leaves.
Corn lower leaves become reddish-purple
Corn
leaves
are
purplish
and
tips
are
brown
and
necrotic.
Maize

21. POTASSIUM
Role or
Function
More than 80 plant enzymes requires K for activation
Synthesis of ATP, translocation of carbohydrates
Synthesis of amino acids, proteins, chlorophyll
Enhance resistance against moisture stress by regulating opening &
closing of stomata and disease resistance
Affects the rate of transpiration & water uptakes, produces strong stiff
straw which inhibit lodging in crops.
Deficiency
symptoms
Older leaves pale green & later chlorosis between veins followed by
scorching or firing with necrotic tissues along margines.
Accumulation of diamine pitrucine in leaves
Stunted growth & bushy appearance
Yield of root & tuber crops affected severely
Lodging, seeds under developed & shriveled, fruit and sugarcane juice
quality affected, prone to disease/ pest/ cold suceptibility
Toxicity
symptoms
Excess K induces Mg deficiency

22. Corn older leaves are chlorotic and leaf edges are burned, but the midrib remains green.
Banana: Older leaves become chlorotic, then necrotic, and the tip of the midrib bends
downward.

23. CALCIUM (IMMOBILE)
Role or
Function
Immobile in plant, Constituent of cell wall, require for cell elongation &
division
Activation of enzymes, role in structure & permeability of cell
memberane
Enhance uptake of NO3-N,
Lower uptake by monocots than dicots
Deficiency
symptoms
Deficiency starts from top (seedling stage), retard growth of tops &
roots,
Failure of terminal buds of shoots & apical tips of roots
Chromosome abnormality, Die-back of fruit trees, blossom end rot in
tomato, bitter pit in apples
Toxicity
symptoms
Iron chlorosis,
P- availability reduces.

24. Celery young leaves are
necrotic and the growing point
dies
Tomato young leaves -twisted and cupped
Calcium deficient bean leaves have
chlorotic and necrotic spots
Guava

26. MAGNESIUM (MOBILE)
Role or
Function
Component of chlorophyll (15-20% Mg present in Chlorophyll)
Structural component of ribosome- protein synthesis
Imparts dark green colour/ Photosynthesis/ glycolysis
Role in oil seed crops, Helps in transport of P
Synthesis of carbohydrates, fats & vitamins
Deficiency
symptoms
Deficiency first appears on older leaves, citrus develops bronzing
disease.
Interveinal chlorosis (veins remain green), Under severe deficiency
causes lower leaves becomes purplish- then turnes red later turns
brown & develop necrotic spots (cotton)
Brittle leaves & tendency to curve upward
Leaves of Mg deficient sugarbeets and potatoes are stiff and brittle and
veins are often twisted.
Low Mg- forage crops causes hypo-magnesemia (Low Mg in blood)
Toxicity
symptoms
Toxicity occures in alkali soils

27. Mg Deficiency in Turmeric
S Deficiency in Turmeric

28. Magnesium deficient tomato; interveinal
chlorosis of older leaves.
Magnesium deficient sweetpotato leaves
become reddish-purple.

29. SULPHUR (IMMOBILE)
Role or
Function
Component of protein (S- containing amino acids cystine, cysteine &
methionine),
Requires for chlorophyll synthesis, Important role in oil synthesis
Requires for the synthesis of co-enzymes A
Involved in synthesis of fatty acids & component of ferridoxin
Deficiency
symptoms
Inhibition of protein and chlorophyll synthesis. S deficiency symptoms
resembles with the symptoms of N and Mo deficiencies. In contrast to N
or Mo deficiency S deficiency symptoms initially occur in younger
leaves, causing them to turn light green to yellow (chlorosis)
Retards growth, Chlorotic/stunted/thin-stemed & spindly appearance
Curling of margines/ organge redish tints on older leaves
Leaf petioles become brittle stem, spinally appearance
Toxicity
symptoms

30. Banana; young leaves are
uniformly chlorotic
Sulfur deficient sorghum; young leaves
are uniformly chlorotic.
Sulfur deficient tomato; young leaves are
uniformly chlorotic.

31. IRON (IMMOBILE)
Role or
Function
Soil critical limit= 4.5 mg kg-1 (ppm)Absorbed by plants as Fe2+ & Fe3+,
activation of enzymes
Component of pophyrin, cytochromes, hames, hematin, ferridoxin,
ferrichrome and haemoglobim (imp. In photosynthesis & respiration)
75% of Fe is associated with chloroplast, required for synthesis of
chlorophyll
Important component of nitrogebnase enzyme essential for N2 fixation
Deficiency
symptoms
Widespread deficiency in Maharashtra
Deficiency occurs in young or top part of plant
Fe deficiency reduces chlorophyll production and is characterized by
interveinal chlorosis with a sharp distinction between veins and
chlorotic areas in young leaves
Under severe deficiency leaf becomes complete white and plant growth
stunted
Toxicity
symptoms
Reduction in growth
Browning of leaf blades & roots
Bronzing of rice (> 300 ppm Fe)

32. Capsicum
Grape
Guava
Turmeric

33. ZINC (IMMOBILE)
Role or
Function
Soil critical limit is 0.6 mg kg-1 (ppm)
Involved in many enzymatic activities
Zn required for synthesis of tryptophan-amino acid necessary for the
synthesis of growth hormone
Component of synthetic & natural organic complexes
Deficiency
symptoms
Widespread deficiency in Maharashtra in sugarcane belt . Deficiency
appers on top leaves, fruits & branches
Reduction of growth hormone causes shortening of internodes/ leaves
are smaller than normal- small narrow thickened leaves
Light-green-yellow or white areas found between the veins of leaves
Bushy or rosette appearance of plant or clustering of leaves, Tissue
death, chlorotic leaf areas, Early loss of foliage
, White bud in sorghum and corn, little leaf of cotton, mottle leaf in citrus
Toxicity
symptoms
Interveinal chlorosis of young leaves
Reddish brown coloration, dry & papery sound
Rolling of leaves, roots brown & necrotic

34. Zinc. Midrib and leaf margin remain green and yellowing of leaf blade. Red
lesions on leaves. Reduced tillering and shorter internodes

35. MANGANESE (IMMOBILE)
Role or
Function
Immobile Soil critical limit is 0.2 mg kg-1 (ppm) and in Plant is 5 ppm
Anonymous role like Fe Involvement in photosynthesis for evolution
of O2
Oxidation-reduction reactions and Enzyme activation (citric acid cycle)
Mn can substitute for Mg in phsophorylating & group transfer
(Electron transport in photosystem)
Manganese helps in chlorophyll formation, Important in nitrogen
metabolism
Deficiency
symptoms
Symptoms usually appears on younger leaves, chlorosis between veins
Chlorotic patches between veins of middle leaves
Chlorotic area becomes necrotic & turns red-brown-reddish brown
Gray specks of oat, marsh spots of peas, Speckled yellows of sugar
beets, pahala blight of sugarcane
, Low Mn favours root-rot disease in wheat.
Toxicity
symptoms
Leaf sheath & lower part of stem of cereals develops minute brown spot
Crinkle leaf of cotton in acidic soils

36. Turmeric- Mn deficiency

37. COPPER (IMMOBILE)
Role or
Function
Immobile Soil critical limit is 2 mg kg-1 (ppm) and in Plant is ppm
Important role in enzyme activity accleration
Protein & carbohydrate metabolism
Helps in utilization of Fe during chlorophyll synthesis
Role in synthesis of complex polymers like lignine & melanine. Indirect
effect on nodule formation
Deficiency
symptoms
Young leaves become yellow & stunted if under severe deficiency
leaves becomes pale & older leaves dieback
In advanced deficiency dead tissues appears along tips & edges of the
leaves (similar to that of K def.)
Ergot infection in wheat & barley is associated with Cu-def.
Cauliflower & cabbage shows fine interveinal cholrotic mottling
, Legumes & tomato shows rolling & distortion
Toxicity
symptoms
Reduce shoot vigour, poor development of flowers & discoloured root
system & leaf chlorosis
Mostly occurs due to sewage sludge, muncipal compost, pig & poultry
manure application or repeated Cu-pesticide spraying.

38. BORON (IMMOBILE)
Role or
Function
Immobile Soil critical limit is mg kg-1 (ppm) and in Plant is ppm
Primary role in Ca metabolism (Boron increases the solubility and
mobility of Ca in plant)
Cell development in meristematic tissue, Proper pllination, fruit & seed
set
Translocation of sugars, starches, N and P
Synthesis of amino acids and proteins, nodule formation, regulation
of carbohydrate
Pollen germination & pollen tube growth
Deficiency
symptoms
Def. symptoms appears on young, newer or emerging leaves
Cessation of terminal bud growth followed by death of young leaves.
Thickened, cracked or curled leaves.
Twisted leaf appearance, flower & fruit development restricted
Sterility & severely impaired seed set.
Discolouration, cracking or rotting of fruit, tubers or roots
Hollow stem of cabbage, Internal cork of apples, uneven thickness of
citrus peel, lumpy fruits, gummy deposits on the fruit

39. MOLYBDENUM (MOBILE)
Role or
Function
Immobile Soil critical limit is mg kg-1 (ppm) and in Plant is ppm
Essential component of nitrate reductase enzyme which catlyses the
conversion of NO3 to NO2
Structural component of nitrogenase enzyme involved in N2 fixation by
Azatobactor
Role in absorption and translocation of Fe
Involvement in protein synthesis
Deficiency
symptoms
Pollen formation disturbs, tasseling delayed flowers & fail to open.
Capasity of the anthers for pollen production is also decreased
Whiptail of cauliflower (Brassica) in which middle leaves starts showing
small interveinal chlorotic patches that becomes translucent at later
stages. Immature grain sprouting in maize
Inward curling of leaves in tomato. Beans develop interveinal chlorosis
called Scald of beans
In wheat middle leaves turns yellow & turns golden yellow.
Yellow spot disease citrus- in which summer flush of leaves become
yellow leaving green zone along the margin.
Toxicity
symptoms
Excess Mo toxic to grazing cattles. (High Mo > 5 ppm causes
molybdenose (teart)) disorder – bone deformation & stunted growth.

40. Chlorin (MOBILE)
Role or
Function
Immobile Soil critical limit is mg kg-1 (ppm) and in Plant is ppm
Osmotic regulation & cation neutralization
Maintaining leaf turgor
Cl act as co-factor in Mn containing O2 evolution for photosynthesis
Cell elongation and stomata opening
In absent of Cl photosynthesis rate reduced
Deficiency
symptoms
Wilting of leaves, curling of leaflets & chlorosis
Necrosis in some plant parts, leaf bronzing & reduction in root growth
Toxicity
symptoms
Thickened leaves & tend to roll with excessive amount of Cl
Storage quality of tubers affected
Increases the osmotic pressure of soil water & therby lower the
availability of water to plants

41. Nickel (IMMOBILE)
.Role or
Function
Component of urease enzyme which catalyses hydrolysis of urea
Nodule weight & seed yield of soybean stimulated by Ni
Deficiency
symptoms
Leaflet tip necrosis in soybean & cowpea due to the role of Ni in N
metabolism
Toxicity
symptoms
Excess Ni causes Fe & Zn deficiency & competes with Ca and Mg
Beneficial Nutrients
1 Sodium
2 Silicon
3 Cobalt

42. Silicon
.Role or
Function
Cell wall structure. Tissue strengthens, draught resistance
Si-reduces activity of invertase in sugarcane which enhance sucrose
production, increases erectness in rice
Disease suppression in rice
Deficiency
symptoms
Leaves and culms become soft and droopy thus increasing mutual shading
reduced photosynthetic activity, Lower or reduced grain yield
Sodium
.Role or
Function
Requires for halophytic plants accumulate in vacuole for maintaining
turgour
Deficiency
symptoms

44. First seen: Younger leaves, Signs: Die back of
leaf tips and edges Common: Not very
common, Natural sources: Soil, nickel chelate

45. Rice
Inhibition of fungal entry in Rice