Plant Responses to Environmental Stress

Plant Responses to Stress

• Plants exhibit various responses to environmental stresses like water, temperature, salt, and oxidative stress.
• These stresses trigger physiological and biochemical changes, leading to adaptations that improve plant survival.

Water Stress Response

• Plants respond to water scarcity by activating various mechanisms.
• These include stomatal closure to reduce water loss, changes in root growth patterns to explore wider soil volumes for water uptake, and production of osmoprotectants to maintain cell turgor.

Temperature Stress Response

• High or low temperatures can compromise plant function and growth.
• Plants adapt by modifying their metabolic activities, altering the expression of stress-responsive genes, and producing heat shock proteins to protect their cells from damage.

Salt Stress Response

• Salinity negatively impacts plant water uptake and metabolism.
• Plants respond by adjusting ion transport, accumulating compatible solutes to maintain osmotic balance, and modifying their root architecture.

Oxidative Stress Response

• Exposure to excessive reactive oxygen species (ROS) causes oxidative stress in plants.
• Plants have antioxidant defense systems that include enzymes like superoxide dismutase, catalase, and peroxidase, and production of antioxidants like ascorbic acid.

Engineering Plants for the Future

• Genetic engineering (or biotechnological techniques) is used to enhance stress tolerance.
• Plants are engineered to better tolerate water and salt stress.

Golden Rice

• Golden rice is a genetically modified variety of rice produced to enhance its vitamin A content.

Flavr Savr Tomato

• Flavr Savr tomato is a genetically modified variety that has an extended shelf life.