Table
Role of Mineral Elementns in Plants
| Element | Obtained as from soil | Regions of plant in which reguired | Functions |
|---|---|---|---|
| Sulphur | SO2+4 | Stem and root tips; young leaves; remobilised during senescence | Constituent of certain proteins, vitamins (thiamine, blotin, CoA) and ferredoxin |
| Iron | Fe3+ | Everywhere; collects along leaf veins | Constituent of ferredoxin and cytochromes; activates catalase; required for synthesis of chlorophyll |
| Manganese (trace) | Mn2+ | Leaves and seeds | Activates certain enzymes (carboxylases) |
| Molybdenum (trace) | MO3+or MO4+ | Everywhere; Mo3+particularly in roots | Activates certain enzymes in nitrogen metabolism |
| Boron (trace) | Leaves and seeds | Required for uptake and utilisation of Ca2+, pollen germination and cell differentiation, carbohydrate translocation. | |
| Copper (trace) | Cu2+ | Everywhere | Activates certain enzymes |
| Zinc (trace) | Zn2+ | Everywhere | Activates various enzymes especially carboxylases, part of carbonic anhydrase and various dehydrogenases; needed for auxin synthesis. |
| Chlorine | Cl– | — | With na+and K+helps determine solute concentration and anion-cation balance in cells; essential for oxygen evolution in photo-synthesis. |
| Nitrogen | NO2NO3–or NH4+ | Everywhere | Constituent of proteins, nucleic acids, vitamins, hormones, coenzymes, ATP, chlorophyll. |
| Phosphorus | H2PO4/PO42- | Everywhere particularly in meristematic tissues | Constituent of Cell membrane, certain proteins; all nucleric acids and nucleotides; required for all phoshphorylation reactions. |
| Potassium | K+ | Younger tissues, withdrawn from older, metabolically less active cells | Helps determine anion-cation balance in cells; involved in protein synthesis; involved in formation of cell membrane and in opening and closing of stomate; increases hardiness; activates enzymes and helps in main-tenance of turgidity of cells. |
| Calcium | Ca2+ | Meristematic tissues; buds, leaves, root tips | Involved in selective permeability of cell membranes; activates certain enzymes; required for development of stem and root apex, and as calcium pectate in the middle lamella of the cell wall. |
| Magnesium | Mg2+ | Leaves; withdrawn from ageing leaves and exported to developing seeds | Activates enzymes in phosphate metabolism; constituent of chlorophyll; maintains ribosome structure. |
