Question

Rate of transpiration is measured by which instrument?

Answer 1

Hint: In 1972 Stephen Hales devised three methods for measuring the rate of transpiration. Transpiration is one of the most important processes of temperature regulation. Transpiration depends on several weather factors, such as wind and humidity, as well as structural factors.

Complete step by step answer:
Measurement Of Transpiration by:
By weighing potted plants
- A potted plant is well watered.
- A plastic bag is warped around the pot to prevent water loss from the soil.
- The apparatus is weighted at intervals and changed in weight is indicated as water loss.
- The recorded decrease in weight over three hours.
By potometer (bubble potometer)
- Cut a leafy shoot from a plant and fit it tightly into the bubble potometer under the presence of water. Seal off all connections with vaseline to ensure no leakage of water should take place.
- Lift the end of the capillary tube from the beaker of water for about 30 s and then replace it to introduce an air bubble into the tube.
- Wait for the bubble to move into the horizontal graduated part of the capillary tube of the setup.
- Record the initial water level of (${{V}_{i}}$ in the burette and the weight (${{W}_{i}}$) of the whole set- up.
- After 24 hours, record the final water level (${{V}_{f}}$) and the weight (${{W}_{f}}$) of the whole set- up.
- Using a photometer, the range of transpiration was measured every three minutes for a total of thirty minutes, resulting in an increased transpiration rate for the plant that had an air current applied to it.
By measuring the humidity of the air
- The leaf is enclosed in a plexiglass chamber and sealed.
- This an experiment to measure transpiration rates in a particular species of herbaceous plant. Plants were the cumulative water loss due to transpiration of water from each plant was measured at 10- minute intervals for 30 minutes. Water loss was expressed as milliliters(ml) of water per square centimetre of leaf surface area.
- Record the data of all groups where the average cumulative water loss by the plants in Group I.

Note: Antitranspirants: These are compounds applied to the leaves of plants to reduce transpiration. They are used on Christmas trees, on cut flowers, on newly transplanted shrubs, and in other applications to preserve and protect plants from drying out too quickly during summertime. This anti transpiration is also used to protect leaves from salt burn and fungal diseases.