PP 501 PRINCIPLES OF PLANT PHYSIOLOGY-I                                                                                 (4L+1P) I

  To acquaint the students with the basic concepts of plant physiology and their application in agriculture.


  Cell organelles and their physiological functions, structure and physiological functions of cell wall, cell inclusions; cell membrane structure and functions.

  Soil and plant water relations, water and its role in plants, properties and functions of water in the cell water relations-cell water terminology, water potential of plant cells. Mechanism of water uptake by roots-transport in roots, aquaporins, movement of  water in plants – Mycorrhizal association on water uptake. Water loss from plants-Energy balance-Solar energy input-energy dissipation at crop canopy level- evapotranspiration, transpiration –Driving force for transpiration, plant factors influencing transpiration rate.

  Stomata structure and function – mechanism of stomatal movement, antitranspirants. Physiology of water stress in plants: Influence of water stress at cell, organ, plant and canopy levels. Indices for assessment of drought resistance. The role of mineral nutrients in plant metabolism: Essential elements, classification based on function of elements in plants.

  Uptake of mineral elements in plants –Mechanisms of uptake-translocation of minerals in plants. Physiological and metabolic functions of mineral elements, critical levels, deficiency symptoms, nutrient deficiency and toxicity. Foliar nutrition.

  Photosynthesis and its importance in bio productivity. Photochemical process, photochemical reactions, CO2 reduction in Calvin cycle, supplementary pathway of C fixation in C4 and CAM plants and its significance. Photorespiration and its relevance. Photosynthesis as a diffusive process, effect of environmental factors on photosynthetic rates. Synthesis of sucrose, starch, oligo and polysaccharides (composition of cell wall). Translocation of photosynthates and its importance in sink growth. Mitochondrial respiration, growth and maintenance respiration, cyanide resistant respiration and its significance.

  Nitrogen metabolism: Inorganic nitrogen species (N2 , NO3 and NH3) and their reduction to amino acids, protein synthesis and nucleic acids. Lipid metabolism- Storage, protective and structural lipids. Biosynthesis of fatty acids, diacyl and triacyl glycerol, fatty acids of storage lipids. Secondary metabolites and their significance in plant defense mechanism. Growth and differentiation.

  Hormonal regulation of growth and differentiation, plant growth hormones and their physiological role, synthetic growth regulators, growth retardants, apical dominance, senescence, fruit growth, abscission. Photomorphogenesis: Photoreceptors, phytochrome, cryptochrome. Physiology of flowering: Photoperiodism and vernalization.

  Estimation of plant water status: Relative water content,water potential estimation by pressure chamber/ psychrometer, membrane stability index (MSI) by conductivity meter. Growth parameters: Growth parameters measurement, growth analysis. Photosynthesis and related parameters:Estimation of chlorophyll/ carotenoid content, separation of photosynthetic pigment using paper chromatography, photosynthesis measurements by IRGA, respiration rate measurement. Amino Acid and proteins: Estimation of total free amino acids, estimation of proteins by Lowry/ Bradford method. Nitrogen metabolism: In vivo nitrate reductase activity assay, nitrogenase activity assay by gas chromatography.

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