1. Mineral Nutrition
Dr. Abdullatif Khan

2. Mineral Nutrients
Mineral nutrients are elements acquired primarily in the form of inorganic ions from the soil. (example: N, P, and K). Mineral absorption by plants is a very efficient process.
Mineral Nutrition
Mineral Nutrition is the study of how plants obtain and use mineral nutrients.
Plants are also proving useful for removing deleterious minerals including heavy metals toxic-waste dumps.

3. Essential Nutrients
An essential element is an intrinsic component in the structure or metabolism of a plant.
An essential element is an element whose absence causes severe abnormalities in plant growth, development, or reproduction.
Two classes:
Macronutrients: required in large amount – C,H,O (from air) N, P, K,S, Ca, Mg, Si
Micronutrients: required in small amount – Fe, Mo, B, Cu, Mn, Na

4. (essential mineral nutrients)
5.1 Essential elements
<- relative concentration in plant tissue
<- not mineral nutrients!
(essential mineral nutrients)
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6. <- biochemical role and physiological function
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9. enzyme activity (electron transfer) * Al, Se, Co….
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* Al, Se, Co….

10. G1: nutrients involved in oxidation and reduction biochemical reactions to form organic compounds (i.e. nutrients that are part of carbon compounds, e.g. N & S).
G2: nutrients involved in ATP reactions, or contribute to cell wall structure or cell wall mechanical properties (i.e. nutrients that are important in energy storage or structural integrity, e.g. P, Si, & B).
G3: nutrients acting as enzyme cofactors and/or involved in regulation of osmotic potentials; free ions dissolved in the plant water (nutrients that remain in ionic form; e.g. K, Na, Ca, Cl, Mg, & Mn).
G4: nutrients involved in electron transfer reactions, e.g. constituent of cytochrome systems involved in photosynthesis or respiration (i.e. nutrients that are involved in redox reactions, e.g. Fe, Zn, Cu, Ni, & Mo).

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12. Part 1: Roots Roots absorb water and minerals in a 4-step process:
Active transport of minerals into root hairs.
Diffusion to the pericycle.
Active transport into the vascular cylinder.
Diffusion into the xylem.

13. Mineral and water uptake

15. Casparian Strip
It prevents excess soil solution from being pulled directly into the central part of the root
In the endodermis portion of root
Its made of suberin and sometime lignin
It stops materials that have been moving through the apoplast and forces them to move into the cytosol of the endodermis. This forces them to cross over the plasma membrane before being allowed to enter the vascular cylinder.
It allows the plant to regulate what moves through the apoplast, cell walls cannot regulate material, only the plasma membrane can.

16. 1. Nitrogen
a constituent of many plant cell components, e.g. amino acids, proteins, & nucleic acids
nitrogen deficiency rapidly inhibit plant growth
Chlorosis (yellowing of the leaves), especially in the older leaves near the base of the plant.
nitrogen –deficient plants may have:
light green upper leaves and yellow lower leaves
slender and woody stems
may reveal purple coloration
in leaves, petioles, and stems
(due to accumulation of
anthocyanin pigment)

17. 2. Sulfur
many of the symptoms of sulfur deficiency are similar to those of nitrogen deficiency, including chlorosis, stunting of growth, and anthocyanin accumulation.
sulfur chlorosis may occur simultaneously in all leaves (mature and young leaves) 

18. 3. Phosphorus
sugar-phosphate intermediates of respiration and photosynthesis
Phospholipids
ATP, DNA, & RNA
Phosphorus deficiency symptoms include:
stunted growth in young plants
dark green coloration of the leaves with necrotic spots (small spots of dead tissue)
purple coloration of leaves (not associated with chlorosis)
slender stems and death of older leaves

20. 4. Silicon
plants deficient in silicon are susceptible to lodging (falling over) and fungal infection.
5. Boron
Evidence suggests that boron plays roles in cell elongation, nucleic acid synthesis, and membrane function
Boron deficiency symptoms:
A characteristic symptom is black necrosis of the young leaves and terminal buds.
Stems may be unusually stiff and brittle.
fruits, fleshy roots, and tubers may exhibit necrosis 

22. 6. Potassium
present within plants as cation, K+.
plays an important role in regulation of the osmotic potential of plant cells
activates many enzymes involved in respiration and photosynthesis
Symptoms of potassium deficiency:
mottled (spotted) or marginal chlorosis, which then develops into necrosis primarily at the leaf tips, at the margins, and between veins.
symptoms appear initially on the more mature leaves toward the base of the plant.
leaves may curl and crinkle.
stems may be weak, with abnormally short internodes.
roots may be susceptible to root-rotting fungi.
weak stems and rotted roots result in lodging of the plants.

24. 7. Calcium (Ca2+)
used in the synthesis of new cell walls, specially the middle lamella.
used in the mitotic spindle during cell division
required for normal functioning of plant membranes
Symptoms of calcium deficiency:
necrosis of young meristematic regions where cell division and cell wall formation are most rapid.
necrosis may be preceded by general chlorosis and downward hooking of the young leaves.
death of meristematic regions results in severe stunting growth.

25. 8. Magnesium (Mg2+)
specific role in the activation of enzymes involved in respiration, photosynthesis, and the synthesis of DNA and RNA.
Mg is part of the chlorophyll molecule.
Symptoms of magnesium deficiency:
chlorosis between the leaf veins, occurring first in the older leaves
premature leaf abscission

26. 9. Chlorine (Cl-)
required for the water-splitting reaction of photosynthesis.
required for cell division in both leaves and roots.
Deficiency symptoms:
wilting of the leaf tips followed by general leaf chlorosis and necrosis
reduced growth and “bronzing” of leaves
roots may appear stunted and thickened near the root tips

28. 10. Manganese (Mn2+)
activation of enzymes, particularly enzymes involved in the tricarboxylic acid cycle (Krebs cycle)
functions in the water-splitting reaction of photosynthesis
Deficiency symptoms:
inter-venous chlorosis associated with small necrotic spots
11. Sodium (Na+)
vital for regenerating phosphoenolpyruvate (PEP), the substrate for the first carboxylation in the C4 and CAM pathways of carbon fixation.
Sodium-deficient plants exhibit chlorosis and necrosis, and may fail to form flowers.

30. 12. Iron (Fe2+ or Fe3+)
a component of enzymes involved in the transfer of electrons (redox reactions)
required for the synthesis of chlorophyll-protein complexes in the chloroplast
Symptoms of iron deficiency:
inter-venous chlorosis, appears initially on the younger leaves.
chlorotic veins and the whole leaf turns white under extreme and prolonged deficiency.

32. 13. Zinc (Zn2+)
required for enzymes activity
required for chlorophyll biosynthesis
Zinc deficiency is characterized by:
small and distorted leaves with margins having wrinkled appearance.
reduction in internodal growth; plants display a rosette habit of growth (a circular cluster of leaves radiating at or close to the ground)

34. 14. Copper (Cu+ or Cu2+)
required for enzymes involved in the transfer of electrons (redox reactions)
Symptoms of cupper deficiency:
production of dark green leaves, which may contain necrotic spots
necrotic spots appear first at the tips of the young leaves and then extend toward the leaf base along the margins.
leaves may be twisted or malformed.
premature leaf abscission

36. 15. Nickel
Urease is the only enzyme known in higher plants that contains Ni2+.
Nickel-deficient plants accumulate urea in their leaves and, consequently, show leaf tip necrosis.
16. Molybdenum
Mo ions are components of several enzymes (e.g. nitrate reductase & nitrogenase)
involved in nitrate assimilation and nitrogen fixation by microorganisms
Molybdenum deficiency symptoms:
general chlorosis between veins and necrosis of older leaves.
flowers formation may be prevented
premature flowers abscission
Molybdenum deficiency may bring about nitrogen deficiency.

38. Treating Nutritional Deficiencies
Traditional farming practices: recycles mineral nutrients but cause leaching of dissolved ions to soil also.
High-production agricultural systems of industrial countries by unidirectional removal from the soil to the crops and addition of fertilizers.
Application of nutrients to the soil by chemical (inorganic) fertilizers. N, P, K – macronutrients are added.
Addition of organic fertilizers by adding plants and animal residues but mineralization (breaking down of organic compounds by microorganisms) is required.
Modification of the soil pH by addition of lime and elemental sulphur.
Foliar application of mineral nutrients by sprays.

42. * Techniques for nutritional studies
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