Transpiration rate
nounPronunciation: /trænspɪˈreɪʃən reɪt/
The measure of water vapor loss from plant leaves and other aerial surfaces, typically expressed as mass of water per unit leaf area per unit time. Transpiration rate is a critical indicator of plant water status and stomatal conductance under abiotic stress conditions.
Plain English
The speed at which plants lose water through their leaves as water vapor.
Etymology & History
Usage
"Transpiration rate decreased significantly in drought-stressed plants due to partial stomatal closure."
Style guide notes: Always specify measurement units and leaf area normalization method when reporting transpiration rate data.
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Related Terms
Frequently Asked Questions
How is transpiration rate measured in research?
Using porometers for stomatal conductance, lysimeters for whole-plant water loss, or infrared thermography for leaf-level measurements.
Why does transpiration rate decrease under drought stress?
Plants close stomata to reduce water loss, directly lowering transpiration rates as a water conservation strategy.
Why Test Candidates on This?
Essential metric in drought tolerance screening, irrigation studies, and physiological stress assessment.
Required skill level: Junior