Soil Fertility and Nutrient management (1+1)

Functions and deficiency symptoms of Magnesium

Magnesium (Mg)

• Mg is a constituent of the chlorophyll molecule and located at its centre, without which photosynthesis by plants would not occur. It is a mobile element and plant absorb as Mg2+ ionic form.

  Functions:

  • Very much essential for photosynthesis.
  • It is involved in the regulation of cellular pH, cation-anion balance and turgur regulation of cells.
  • Necessary for protein synthesis.
  • Activator of enzymes in carbohydrate and ATP metabolism.
  • Essential for the formation of oils and fats
  • It is required for stabilization of cell membranes.

  Deficiency:

  ¥ Interveinal chlorosis of lower leaves and in extreme cases becomes necrotic.
  ¥ Leaves remain in small and brittle even in final stages.
  ¥ Twigs may become weak and premature dropping of leaves results in heavy loss of fruit crops.
  ¥ Inhibits nitrate reduction and the production of photo hormones.
  ¥ Stalk necrosis or stem ‘Die back’ in a Vine plant.
  Excess of Mg absorption becomes poisonous leads to browning of roots as a result growth is ceased and death of roots and leaves. It can be counteracted by CO2 antagonistic action.