How could plants with inrolled/infolded leaves reduce water loss!?

Question

How could plants with inrolled/infolded leaves reduce water loss!?

Answer 1

Hi Partoa,

When a leaf is flat, the sun heats the leaf's surface temperature, which increases transpiration.

When a leaf rolls around itself, it is using itself to shade the rest of the leaf and, therefore, exposing a smaller surface to the sun.  With a smaller surface being heated by the sun, there is less transpiration.

[NOTE: For many plants infolding/inrolling of leaves is an indication the plant has a disease and other health problem.]

I hope this is of some help to you.

Hiking Tony

Answer 2

Think about it.  Rolling or infolding reduces the profile for interception of sunlight.  Direct sunlight will tend warm a leaf up by several degrees above the surrounding air temperature.  The warmer the leaf the greater the tendency to lose water by evapotranspiration.  So, infolding is likely to be a way to conserve water.  I've seen tomato leaves do this on a sunny day.  Quite intelligent response wouldn't you say?