Understanding Ecophysiology

• Ecophysiology is the study of how living organisms respond to their environment.
• It examines how internal systems are influenced by external factors.
• Climate and nutrients are external factors that influence internal systems

Climate

• Temperature, rainfall, and sunlight impact organisms.
• Example: Plants adapting to grow in deserts with limited water.

Nutrients

• Availability of essential resources is key for survival.
• Example: Animals adjusting feeding patterns in nutrient-poor environments.
• Explains how organisms adapt to survive in challenging environments by combining ecology and physiology.
• Ecology is the study of the environment.
• Physiology looks at how organisms function.
• Practical example: How animals stay warm in freezing temperatures.
• The environment includes physical, chemical, and biotic elements.

Physical Environment

• Consists of light intensity, temperature, and gravity.

Chemical Environment

• Includes water, carbon dioxide, oxygen, nitrogen, minerals, and toxins.

Biotic Environment

• Covers soil organisms, competition for space and other resources, herbivory, and allelopathy.
• Plant physiology is the study of how plants work internally.
• It explains the physical and chemical functions inside plants.

Plant Ecology

• Explores the interrelationships between organisms and their environment.

Plant Ecophysiology

• Combines physiology and ecology to study how plants respond to their environment on a physiological level.
• Example: Plants adapting to different light, water, and temperature conditions.
• Plant ecophysiology studies how plants work and react to their environment, focusing on growth, reproduction, and distribution.
• It examines physical, chemical, and biological environmental factors.
• Plant ecophysiology includes physiology, biochemistry, and molecular biology.
• Genes and proteins help plants adapt.
• Plant ecophysiology helps understanding of plant responses to climate, soil, and competition
• This makes it crucial for agriculture, conservation, and environmental efforts.

Plant Ecophysiology

• An experimental science that seeks to describe the physiological mechanisms underlying ecological observations.
• Ecophysiologists address ecological questions about growth, reproduction and survival.
• They look at abundance and geographical distribution of plants
• These processes are affected by plant interactions with physical, chemical, and biotic components of the environment.
• Eco-physiologists study why species live in certain areas, successful reproduction, and environmental impacts on survival.
• Three main filters historical, physiological and biotic; determine where plants can survive and thrive.

Historical Filter

• Determines if the plant can reach an area
• Includes barriers like mountains and oceans.

Physiological Filter

• Examines if the plant can survive in the environment.
• Considers water, temperature, and soil conditions.

Biotic Filter

• Assesses if the plant can compete with other plants and animals.
• It favors strong competitors.
• If plants pass all 3 filters, they can grow in an area, however filters may change depending on the environment
• Historical, physiological, and biotic filters change due to volcanic eruptions, floods, and species introductions.
• Climate, soil, and species changes bring new challenges, with survival dependent on adaptation, growth, and reproduction.
• Plants in an area are those that arrived and adapted successfully.
• Stress on a plant is any environmental or biotic factor that reduces the rate of a physiological process below its maximum.
• Abiotic or biotic processes can generate stresses.

Stress Examples

• Low nitrogen, heavy metals, high salinity, and neighboring plants.
• Time scale of physiological response helps understand how a plant copes with changes.

Immediate Response

• Involves quick reductions in processes to survive stress.

Acclimation

• Temporary changes like deeper roots or thicker leaves, which occur from individual adjustments.

Adaptation

• Long-term genetic changes in a population to handle stress across generations.
• The stress response is immediate and detrimental, causing a decline in performance.
• Acclimation is morphological and physiological adjustments by individual plants to compensate for the decline.
• Adaptation is an evolutionary response resulting from genetic changes to compensate for decline.
• After initial stress, plants retain a "memory" to respond better in future.
• Whole-plant adjustments also occur, like producing new materials or activating defense systems.
• Plant interactions within seconds-minutes require rapid acclimation responses.
• Environmental changes need evolved sensing and acclimation mechanisms.

Consequences of Stresses

• Biotic and abiotic stress consequences are ethylene, reactive oxygen species, nitric oxide, jasmonic acid, green leaf volatile(s), and ozone.
• Plants respond to climate, soil, and competition making them important for agriculture and conservation.
• Stress causes impacts in different areas causing reduced soil quality, decreased plant quality and quantity
• Key environmental stimuli are water, oxygen, nutrients and temperature
• A plant's response depends on when, where, and what impacts survival which affects: Death, growth, reproductions and distribution.
• The roots are not as affected by heat stress where aerial parts of the plant are
• A plant's survival relies on how it adapts to changing conditions through different stimuli and adjustments.

Plant Stimuli Responses

• Plants accurately detecting changes like light signals.
• Ability to respond to outside stimulus while still changing metabolism and development

Transduction

• The act of signals sent from one plant to another. The trigger can be a response that helps their survival.
• Perception involves detecting environmental changes.
• Transduction sends signals to trigger responses.
• Adaptations adjusts growth.
• Plants respond to environmental stresses by changing internal processes.

Steps For Plants To Respond To Stress

• 1. Stress Detection: detecting signals like heat and lack of water.
• 2. Signal Transmission: Sends cell signals for plants to respond to a threat.
• 3. Gene expression is activated and helps plants survive
• 4 .Adaptation. Plants begin to grow again under stressful conditions.
• Plant roots are less likely to suffer the heat in aerial parts of the planet.
• Local plant organs response as a survival method.
• Plants that can do this has a much higher chance of survival
• Plants respond to stress on both cellular and whole plant levels through recognition, transfer, and response.
• Plants detect signals to regulate behavior
• responses rely on transduction, where information is transferred from areas of recognition to areas of response.
• Plants adapt to changing environmental conditions by changing expression patterns.
• Gene expression ensures greater resistance for the given stresses.
• To further improve plant responses, stress-response genes versus stress-specific ones must be present.
• Protective genes must be increased for those with oxidative stress.
• Plants detect extracellular signals, which bind to plasma protein receptors and are transduced.
• A plant's cells respond to water stress by using abscisic acid (ABA).
• A time of drought causes stress controlled by a lack of hormone which leads to a stop in water usage.
• Plants respond to drought by reducing growth and adjusting water balance.
• Plants adjust to being able to maintain water flow and maintain self turgor.

During Resistance Processes Plants Have Several Options

• Developed root systems and thick leaves
• Smaller Vascular. Plant bundles with fewer vessels to lower amount of transpiration from the plant
• Increase in Proline. Glycine, dehydration, osmosis and etc
• Senescence is accelerated creating better water retention in the plant
• Plants respond to these stresses by the way the soil is managed in their surrounding environment