What are xerophytic plants?
Plants with adaptations which allow them to live in hot and dry conditions are called xerophytic plants.
What are the adaptations which allow plants to survive in the hot desert environment?
Structural adaptations are important to plant’s survival in the desert. The following adaptations allow plants to survive in the hot desert environment:
Small leaves – these ensure that less water is lost from the plant by transpiration because the leaf has a smaller surface area.
Tap roots – these are long roots that reach deep under the ground to access water supplies.
Spines – some plants have spines instead of leaves eg cacti. Spines lose less water than leaves so are very efficient in a hot climate. Spines also prevent animals from eating the plant.
Many plants in the desert conserve water by not having any leaves at all. Cacti are the most prolific of this plant type. Many cacti have spines in place of leaves, which conduct photosynthesis and catch dew when the climate is right. These small structures also reflect light, further reducing water loss. During heavy rains, cacti will grow temporary root systems and absorb water. They will then shed the roots when the ground has dried.
Wax coating on leaves – some leaves have a thick, waxy skin on their surface. This reduces water loss by transpiration.
Water storage – some plants, known as succulents, store water in their stems, leaves, roots or even fruits. Plants which store water in their leaves and stems also have a thick waxy skin so that they lose less water by transpiration.
For example plants such as aloes are equipped with fleshy leaves that contain much of their water supply. Because of their moist inner bodies, these plants are called succulents. They typically feel spongy and when cut open are filled with a pulpy flesh, protected by a waxy outer layer.
PRACTICE QUESTIONS
QUES . Which of the following leaf modifications occur(s) in the desert areas to inhabit water loss? UPSC 2018
1 . Hard and waxy leaves
2 . Tiny leaves
3 . Thorns instead of leaves
Select the correct answer using the code given below:
a . 2 and 3 only
b . 2 only
c . 3 only
d . 1, 2 and 3
Ans d
