Plant Physiology

The course “Plant Physiology” is a Core Course in Semester V of B.Sc. Botany under the Choice Based Credit System (CBSE). The course has been meticulously designed to acquaint and enlighten the students about key concepts regarding various functional aspects of plants and complement the understanding of different topics of Plant Physiology, with special focus on uptake and translocation of water and nutrients, physiology of flowering and the role of plant growth regulators and photoreceptors.The objectives of this course are to give the target students an understanding of:

• Water Potential and its components, and how they drive the flow of water
• How the ascent of sap occurs in xylem
• Transpiration and mechanism of stomatal movement.
• The importance of mineral nutrition especially the role and deficiency symptoms of essential elements
• How nutrients are uptaken and transported across cell membranes through active and passive processes
• How translocation in the phloem occurs and its dependency on phloem loading and unloading
• Discovery, chemical nature and physiological roles of plant growth regulators and some photoreceptors
• Physiology of flowering with special focus on photoperiodism and vernalization
• Seed dormancy
• Growth and development
• Stress Physiology

COURSE LAYOUT

Weeks Weekly Lecture Topics Assignments (No. & Type)*Week 1 : Water and life, Physical chemical properties of water, Water Potential and its components, Aquaporins 5 SubjectiveWeek 2 : Diffusion, osmosis, absorption (SPAC), Ascent of sap, Transpiration: Its importance and factors affecting transpiration, Mechanism of opening and closing of stomata 5 SubjectiveWeek 3 : Essential macronutrients and micronutrients: Role, deficiency and toxicity, Methods of study and use of nutrient solutions, Chelating agents, Biological membrane: Structure and Function, Chemical properties of soil (pH and soil nutrient status) 5 SubjectiveWeek 4 : Soil as a nutrient reservoir and transport of ions across cell membrane (passive absorption), Active absorption, Mineral nutrient uptake (mechanism), Phloem transport 5 SubjectiveWeek 5 : Phloem loading, Phloem unloading, Source–sink relationship, Auxins—history of discovery, biosysnthesis and mechanism of action 5 SubjectiveWeek 6 : Gibberellins—history of discovery, biosysnthesis and mechanism of action, Cytokinins—history of discovery, biosysnthesis and mechanism of action, Abscisic acid—history of discovery, biosysnthesis and mechanism of action, Ethylene – history of discovery, biosynthesis and role in plant growth and development 5 SubjectiveWeek 7 : Bioassay of Auxins, Cytokinins and Gibberellins, Bioassay of Abscisic acid and Ethylene, Brassinosteroids: discovery, chemical nature, bioassay and physiological roles, Jasmonic acid: discovery, chemical nature, bioassay and physiological roles 5 SubjectiveWeek 8 : Development of flower as a modified shoot, Physiology of flowering, Flowering and photoperiodism (Short-day, Long-day and Day-neutral plants), Seed dormancy (types) and seed germination 5 Subjective
Week 9 : Phytochromes—discovery, role and mechanism of action, Cryptochromes: discovery, chemical nature, role in photomorphogenesis, mode of action, Phototropins: discovery, chemical nature, role in photomorphogenesis, mode of action, Low energy responses (LER) and high irradiance responses (HIR) 5 SubjectiveWeek 10 : Growth: phases and kinetics, Flowering plants: annuals, biennials and perennials, Senescence—mechanism and role, Leaf abscission and senescence 5 SubjectiveWeek 11 : Plant movements, Leaf adaptations to water stress, Morphological and anatomical responses of plants to water, Physiological responses of plants to water stress 5 SubjectiveWeek 12 : Morphological, anatomical and physiological responses of plants to salinity, 5 Subjective