Drought Stress
Drought stress is a crucial limiting factor for plant life on earth.
It’s the reason most plants can’t survive in deserts. Drought as well as freezing limits the water supply of plants.
What’s the problem with poor water supply?
Well, plants can’t grow under drought stress because they are lacking the pressure within their cells which would allow them to grow. To avoid further water loss they have to keep their stomata closed during drought.
But then photosynthesis isn’t possible either.
Exactly. And increasing dehydration can damage the water transport system and, subsequently, the living cells.
But – Plants have developed lots of adaptation strategies to withstand drought stress. For example, some plants develop extensive root systems; others rely on resistant water transport systems, thick cuticles, or efficient stomata regulation…
…and succulents even store large amounts of water in their tissue. This way, they can buffer water losses and store CO2 for photosynthesis. They have to open the stomata only during the night when transpiration is low.