Mineral nutrition

What is minerals?

naturally occurring inorganic solid that has a definite chemical composition, and an ordered internal structure.

What is nutrition?

Nutrition is a process of taking food and using it growth ,repair , reproduction and maintenance of body.

The word nutrient come from the Latin word which means feed

Essential of mineral elements

Most of the mineral present in soil can enter through the root.

Some plant species accumulate selenium some other gold. While some plants growing near nuclear test site take up radioactive strontium.

Criteria for essentiality.

1. element must be absolute necessary for supporting normal growth and reproduction, absence of element the plant do not complete their life cycle or falls seeds.
2. requirement of element must be specific and not replaceable by another element. Deficiency of  any element cannot be met by supplying some other element.
3. Element must be directly involved in metabolism of plant.

the element are further divided into two broad categories based on their quantitative requirement.

• macronutrients and
• Micronutrients

Macronutrients

These are generally required in plant tissue in large amount that is excess of 10 m mole per kg of dry matter.

They have nine number of element 

example carbon ,hydrogen ,oxygen, nitrogen, Phosphorus ,Sulphur, potassium ,calcium and magnesium.

Carbon, hydrogen and oxygen are mainly obtain from CO2(carbon dioxide) and H2O(water).

Micronutrients

Micronutrients are needed in very small amount that is less than 10 m mole per kg of dry matter.

Micronutrients are 8 in number example iron, manganese, copper, molybdenum, zinc, boron , chlorine and nickel.

Iron is large amount in comparison to other micronutrients while molydenum required in minimum quantity.

Total 17 element are essential elements

Beneficial element are sodium, silicon, Cobalt and selenium.

Structural elements carbon ,hydrogen ,Oxygen and nitrogen.

Potassium important role in opening and closing of stomata.

Magnesium in chlorophyll and 

phosphorus in ATP

Carbon, hydrogen, oxygen, nitrogen, phosphorus and sulphur are protoplasmic element.

Framework  element carbon ,hydrogen and oxygen.

Deficiency symptoms

 deficiency of any essential element plant show certain morphological change . These indication are called deficiency symptom.

on the basis of mobility of element in the plant deficiencies symptoms are two types.

1. Appeared first in older tissue
2. Appear first in younger tissue

Appear first in older tissue

Mobile element appeared in older tissue when the plant exported to young tissue.

Example nitrogen ,Phosphorus, potassium magnesium and sulphur.

Appear first in the young tissue.

Immobile element are not transported out of the mature organ because they are structural element and not release.

Example calcium.

Prevent deficiency symptom in plants

• Chlorosis 

1. Loss of chlorophyll leading to yellowing of leaves.
2. Deficiency of element are nitrogen ,potassium , magnesium, sulphur, iron , manganese and  molybdenum.

Necrosis

1. Death of tissue particularly leaf tissue.
2. Deficiency of elements are calcium, magnesium, copper and potassium.

Inhibition of cell division

• Inhibition of cell division
• Deficiency of elements are nitrogen ,potassium, sulphur and molydenum.

Delay in flowering

• Delay in flowering
• Deficiency of elements are nitrogen ,Sulphur and molybdenum.

Toxicity of micronutrients

• Requirement of micronutrients always low amount,

 While moderate decrease cause deficiency symptom and moderate increase cause toxiCity

Example manganese toxicity is appearance of brown spot surrounded by chorotic veins.

Excess of manganese may Induce deficiency of iron ,magnesium and calcium.

Role of micronutrients and macro nutrients

Nitrogen

• Essential nutrient element required by plant in the greatest amount.
• Nitrogen is required all parts of plants in meristematic tissue and metabolic active cell.
• Constituent of protein, nucleic acid, vitamins and hormones.

Phosphorus

• Phosphorus is absorbed by plant in the form of phosphate ions.
• Phosphorus is constitution of cell membrane ,certain proteins , nucleic acid and nucleotide.

Potassium

• Absorb as potassium ion,
• It is require more abundant quantity.
• Potassium helps to maintain anion- cation balance in cell,
•  Protein synthesis,
•  opening and closing of stomata,
•  activation of  enzymes and  turgidity of cell.

Calcium

• Calcium absorbed from the soil in the form of calcium ions,
• Calcium is required for meristematic and differentiated tissue.
• Synthesis of cell wall
• Calcium pectate in the middle lamella,
• Formation of mitotic spindle
• Accumulator in older leaves
• Activate certain enzymes
• Regulating metabolic activity.

Magnesium

• Activate the enzyme of respiration, and photosynthesis,
• Involve in the synthetic of DNA and RNA,
• Magnesium is constituent of the ring structure of chlorophyll.
• Help to maintain ribosome structure.

Sulphur

• Plant obtain sulphur in the form of sulphate.
• Sulphur is found in two amino acid cysteine and methionine.
• Constituent of several coenzyme, vitamins and ferredoxin.

Iron

• Plant obtain iron in the form of ferric ions,.
• Required in larger amount comparison to other micronutrient. 
• Constituent of protein involved in the transfer of electron like ferredoxin and cytochrome.
• Activate catalase enzymes.
• Formation of chlorophyll is essential.

Manganese

• Absorb in the form of manganous ion.
• Activate many enzymes involved in photosynthesis and respiration and nitrogen metabolism.

Zinc

• Activate enzymes especially carboxylase also synthesis of auxin.

Copper

• Absorb as cupric ions
• Essential in metabolism in plant

Boron

• Utilisation of calcium
•  Membrane functioning
•  pollen germination
•  cell differentiation
•  cell elongation and 
• Carbohydrate translocation

Molybdenum

• Plant obtain in the form of molybdate ion
• Component of several Enzyme including nitrogenase and nitrate reductase are participate in nitrogen metabolism.

Chlorine

• Absorb in the form of chloride anion
• Sodium and potassium ion it help in determining solute concentration and anion- cation balance in cell.
• Essential for water splitting reaction in photosynthesis.