Mineral Nutrition Mineral Nutrition In remote Past it

Mineral Nutrition

Mineral Nutrition • In remote Past, it was realized that land plant obtain nourishments from soil. • During 1 st half 19 th century, Plants grow and develop in the presence of certain chemical elements---Essential elements • These elements are taken by plants as inorganic ions • Source of inorganic ions in soil----Minerals

Definition • Mineral nutrition was suggested to refer to an inorganic ion obtained from soil and required for plant growth

Essential elements • 16 • Required for plant growth and maintenance • Their absence develop in plants deficiency symptoms due to nutrition disorder • Criteria • Plants cannot complete its life cycle i. e. not form viable seeds • It forms any part of molecules or constituent of the plant that is itself essential in plant e. g. N in proteins and Mg in chlorophyll

Macronutrients • • • C, H, O N, P, K, S, Mg, Ca Microelements Zn, Fe, Cu, Mn, Mo, B, Cl Beneficial elements Na (Salt-marsh plants C 4 Pathway ), Si (Grasses), Co (Wheat, and legume species), Se (Saline soil plants), Ni (Essential compnent for enzymes)

Role and Deficiency Symptoms of Macronutrients

Carbon, Hydrogen and Oxygen (C, H and O): • These are the non-mineral essential elements commonly enter a plant body as CO 2, H 2 O. • These elements are the building blocks of macromolecules and constitute over 90% of the total dry matter of the plant. • Hence these are commonly known as framework elements.

Nitrogen Role • Nitrogen is essential for Amino acid formation. • Necessary for cell division and for plant growth. • Necessary part in Photosynthesis formation. • Essential formation and uses of carbohydrates. • Affects the anabolic and catabolic reactions in plants.

Deficiency Symptoms • Lower leaves show chlorosis (lack of chlorophyll) • Necrosis in older leaves. • Reduction in quality. • Crop mature early but of poor quality. • Yellow discoloration of leaf tips.

Role of phosphorous • It is a constituent of phospholipids (membrane lipids), nucleic acids, nucleotides, coenzymes, ATP, metabolic intermediates, sugar phosphates in photosynthesis etc.

Symptoms of phosphorus in plants • (i) Purple or red pigmentation on leaves, Older leaves affected first and become dark brown • (ii) Premature fall of leaves and floral buds • (iii) Delay in seed germination • (iv) Stunted and slender stem in young plants, • (v) Accumulation of carbohydrates in Glycine max (Soybean), • (vi) Vascular tissues reduce in tomato plants.

Role of Potassium in plants • (i) Essential for stomatal opening, translocation of sugar, protein synthesis, activation of enzymes and maintenance of cell turgor. • (ii) Determine anion-cation balance in cell.

Symptoms of deficiency potassium in plants • (i) Chlorosis followed by necrosis of leaf tips, margins and between veins • (ii) Loss of apical dominance, leads to rosette or bushy habit • (iii) Loss of cambial activity • (iv) Disintegration of plastids • (v) Rate of respiration increases • (vi) Dieback of shoots i. e. progressive death from shoot tip towards base

Role of calcium in plants • (i) Used in synthesis of calcium pactate in middle lamella of cell wall • (ii) Involved in normal functioning of cell membrane • (iii) Used in formation of mitotic spindle • (vi) Activates certain enzymes like ATPase, kinases and succinate dehydrogenase.

Symptoms of calcium in plants • (i) Stunted growth • (ii) Chlorosis, and deformation in young leaves, • (iii) Necrosis of young meristematic regions such as root tips or young leaves.

Role of magnesium in plants • (i) Important constituent of chlorophyll • (ii) Maintains ribosome structure and chromatin fibre • (iii) Activates enzymes in respiration, photosynthesis and synthesis of DNA and RNA.

Symptom of magnesium deficiency in plants • (i) Chlorosis between the leaf veins • (ii) Necrotic or purple spots on older leaves. • (iii) Extensive development of chlorenchyma and scanty pith formation. • (iv)Reduced photosynthetic activity. • (v)Reduction in enzyme activity.

Role of Sulphur in plants • • Essential element of Amino acid. Help in formation of enzymes and vitamins. Essential for seed formation. Play important role in chlorophyll formation.

Symptoms of Sulphur deficiency in plants • Reduction in protein and chlorophyll synthesis. • Young leaves become yellow from green colour, If not protected all plant become pale green. • Stem become short. • Stunted growth of plant.