Plant Physiology - Lecture Notes - O. M. Tarnopilska 2019

1. Fundamentals of Plant Physiology
1.3 Modern Trends in Plant Physiology

Classical plant physiology distinguishes six fundamentally important areas:

1. Biochemical approach:

·examines the Functional Significance of various organic substances produced in plants during Photosynthesis and Respiration;

·reveals the regularities of mineral Nutrition in plants, as well as the pathways of Biosynthesis of Organic compounds from simple Mineral Substances (carbon dioxide, Water, ammonia, nitrates, sulfuric and phosphoric acids, magnesium, calcium, potassium, and trace elements);

·explores The Role of minerals as colloid state regulators and catalysts, their involvement in the synthesis of organic compounds, and their function as centers of electrical phenomena within The Cell.

2. Biophysical approach:

- studies cellular energetics, plant electrophysiology, and the physicochemical regularities of plant Functions (water regime, ROOT nutrition, growth, irritability, photosynthesis, and respiration).

3. Ontogenetic approach:

- investigates age-related regular changes in plant development driven by internal biochemical and biophysical processes, morphogenesis, and potential Methods for controlling plant development (Photoperiodism, vernalization, light culture, plant hardening, etc.).

4. Evolutionary or comparative approach:

·identifies the Features of Phylogeny of a species or individual specimens;

·establishes the Characteristics of Individual plant development under specific environmental conditions;

·investigates ontogeny as a genotype function shaped through phylogeny, alongside age-related plant changes dependent on hereditary constitution and environmental factors.

5. Ecological approach:

·examines internal processes of the plant Organism in relation to the external environment;

·explores the application of fertilizers in the form of balanced nutrient blends, the creation of optimal light and water regimes through rational plant spacing, and the enhancement of protein content, sugar levels, and Plant resistance to adverse environmental conditions;

·the objective of this approach is to develop agricultural practices that effectively influence plant performance in crop production.

6. Synthetic or cybernetic approach:

·identifies general regularities of plant growth, energetics, and kinetics of interconnected processes: photosynthesis, respiration, nutrition, and Organogenesis. Complex life processes can only be understood by taking into account the integrity of the entire organism. A plant, much like an animal, is an exceptionally complex, integrated, and self-regulating cybernetic system;

·cybernetics investigates specific biophysical and biochemical adaptive processes and organismal responses, while developing methods for regulating and controlling processes within biological systems.

At The current stage of plant physiology development, alongside the six main areas, several other research fields have emerged:

1. Plant cell functions and organelle biogenesis.

2. Regulatory and integrative systems within the plant organism.

3. Photosynthesis, its Organization and productivity.

4. Respiration and its connection to the physiological processes of the plant organism.

5. Transport of substances in plants.

6. Plant water relations.

7. Mineral Nutrition of Plants, the role of macro- and microelements.

8. Physiology of symbiotic Nitrogen Fixation.

9. Plant GROWTH AND DEVELOPMENT, reproductive physiology, and Aging mechanisms.

10. Phytohormones, growth inhibitors, and their synthetic analogues.

11. Plant Stress physiology, physiological adaptation, and plant stress states.

12. Plant Pathophysiology and allelopathic phenomena.

13. Physiological Basis of the production process.

14. Evolutionary plant physiology.