Plant Drought Stress: Effects, Mechanisms and Management

What is the most severe environmental constraint to plant productivity?

Which factor probably exceeds losses from all other causes in reducing crop yield?

What does drought stress primarily affect in plants?

What aspect of plant physiology does drought stress disturb?

Which institute is associated with the International Rice Research Institute (IRRI)?

Where have the effects of drought stress on plant growth and physiology been reviewed?

What is the main reason for the reduction in CO2 assimilation by leaves during drought stress?

Which nutrient helps in osmotic adjustment to withstand drought stress?

What is the role of low-molecular-weight osmolytes during drought stress?

Which plant growth substance modulates the plant responses towards drought?

What are the major deterrents to growth in plants under drought stress?

Which mechanisms help plants withstand drought stress?

What molecular-level mechanisms have been identified as drought-responsive genes?

How can plant drought tolerance be managed?

Environmental Constraints to Plant Productivity

Drought is the most severe environmental constraint to plant productivity, exceeding losses from all other causes in reducing crop yield.

Effects of Drought Stress on Plants

Drought stress primarily affects plant growth and physiology.
Drought stress disturbs the plant's water relations, carbon metabolism, and nutrient uptake.
The effects of drought stress on plant growth and physiology have been reviewed by the International Rice Research Institute (IRRI) and the University of California, Riverside.

Physiological Responses to Drought Stress

Drought stress reduces CO2 assimilation by leaves, mainly due to stomatal closure and reduced photosynthetic activity.
Potassium helps in osmotic adjustment to withstand drought stress by facilitating the uptake of water and minerals.
Low-molecular-weight osmolytes (e.g., proline, glycine betaine) play a role in protecting plants against drought stress by maintaining cellular turgor and stabilizing membranes.

Plant Hormones and Drought Stress

Abscisic acid (ABA) modulates the plant responses towards drought, triggering stomatal closure, reducing water loss, and inducing gene expression for drought tolerance.

Drought Stress and Plant Growth

Major deterrents to growth in plants under drought stress include reduced water availability, impaired nutrient uptake, and increased oxidative stress.
Mechanisms that help plants withstand drought stress include drought avoidance, drought tolerance, and drought recovery.

Molecular Mechanisms of Drought Tolerance

Drought-responsive genes have been identified, including those involved in ABA signaling, osmoregulation, and antioxidant defenses.

Managing Plant Drought Tolerance

Plant drought tolerance can be managed through breeding for drought-tolerant crops, improving irrigation systems, and implementing conservation agriculture practices.

This review article discusses the effects, mechanisms, and management of drought stress in plants. It covers the research on plant drought stress and its implications on agriculture and crop management.