Plant Physiology 1400-114FR

The subject of the lectures will be characterization of fundamental life processes in the cells, tissues and whole organism, dependence between the processes and integration of plant function under changing environmental conditions. The following topics will be discussed:

Signalling, phytohormones and plant movements. Signal transduction in plants: receptors, signal transducers. Decoding of calcium signal. The role of phytohormones. Plant movements: tropisms, nasties, autonomic.
Photomorphogenesis. Role of light in plant morphogenesis. Receptors of light: phytochromes, cryptochromes, antocyjanins, flavonoids and their role in photomorphogenesis.
Flowering. Factors inducing flowering in plants. The role of assimilates, hormones, light and temperature. Multifactor model of flowering control.
Germination. Chemical components of seeds. Phases of seed germination and their characteristics. Seed vigor and viability. Seed dormancy and its removal.
Plant ageing. Monocarpic and polycarpic plants. Role of hormones, environmental and genetic factors in the ageing of plants and their organs. Mechanisms of plan ageing.
Photosynthetic activity. Structure of photosynthetic apparatus; light reactions: photosynthetic electron transport and photophosphorylation, assimilation and reduction of CO2, photosynthetic types: C3, C4 and CAM, photorespiration. Regulation of sucrose and starch synthesis.
Respiration, plant respiratory chain and its characteristic features, efficiency of oxidative phosphorylation, cyanide resistant respiration and the role of alternative oxidase, reactive oxygen species generation, respiration in light, the role of mitochondria in photosynthesis and integration of cell metabolism.
Mineral nutrition. The role of macro and micro elements. Deficit of some ions (phosphate deficiency). Mycorrhiza. Nitrate assimilation and metabolism. Atmospheric nitrogen fixation.
Water in the cell and in plant. The physical and chemical properties of water. Main components of water potential. Diffusion, osmosis and bulk flow. Aquaporins. Water uptake from soil and transport to xylem. The cohesion-tension theory. Stomata and transpiration.
Transport of organic and inorganic molecules. Transport mechanisms in plants. Apoplast and symplast. Short-distance transport (membrane transport, transport of low- and high molecular mass compounds through plasmodesmata). Long-distance transport (phloem loading, phloem transport, phloem unloading). Long distance transport of water and ions in xylem
Integration of plant functions. Long-distance signaling in plants: biochemical and biophysical signals. Transport of transcription factors and RNA molecules as a part of regulation of plant development and defense responses. Symplasmic domains.
Plant stress. The basic concepts of stress. Susceptibility, resistance, adaptation and acclimation. Environmental stress factors. Early responses and changes in metabolic processes. Compatible solutes and stress proteins. Oxidative stress and fotoinhibition. Role of hormones and secondary metabolites.

Laboratory:
• Photosynthesis.
Characteristic of C3 type of photosynthesis. Isolation of chloroplasts. Hill reaction. Spectrophotometrical determination of PSII activity.

• Metabolism of water and inorganic ions.
Symptoms of mineral deficiency. Effect of pH on cation and anion uptake. Nitrogen assimilation, determination of nitrate reductase activity. Determination of osmotic potential.

• Respiration.
Oxygen uptake by root system. Regulation of respiratory gas exchange (inhibitors of respiratory electron transport). Cyanide resistant respiration. Anaerobic respiratory metabolism (ethanol production, activity of alkohol dehydrogenase).

• Plant pigments
Quantitative and qualitative composition of assimilation pigments depending on various environmental factors and plant age. Separation of pigments by thin layer chromatography. Fluorescence of chlorophyll a, in vivo measurements.

• Germination of seeds
The role of phytochrome, gibberelin and abscicis acid in the regulation of seed germination. Modifications of amylase activity and starch content over the course of barley’s seed germination. Lipid-saccharide conversion during sunflower seed germination.

• Organogenesis of plants in vitro.
Induction of organogenesis of flax in vitro. The role of different hormones in regulation of organogenesis.

• Hormonal regulation of plant growth.
The role of auxins in the regulation of tropic curvature. Effect of gibberelin on the growth of dwarf pea epicotyl. Apical domination.

• Plant reactions to stress factors.
Antioxidant systems in plants: peroxidase activity and reduction of ascorbate; the level of lipid peroxidation in leaf tissues.

• Senescenece of plant tissues.
The role of cytokinins and ethylene in the regulation of leaf senescence. Seed aging.

• The role of vascular system in plants.
Long-distance transport in plants. Transduction of action potential wave.