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Xerophytes are plants that have adapted to grow in areas with low or no precipitation at all. They are also called desert plants. They have an extensive root system which helps them reach underground water. eg. Cacti.

Hydrophytes are plants that have adapted to grow in areas of high precipitation or inside waterbodies. They have a thick layer of water resstant cuticle on them. eg. Lillies.

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Xerophytes

• Plant adapted to live in dry conditions. Common adaptations to reduce the rate of transpiration include:
• Thick waxy cuticle: The cuticle cuts down water loss in two ways: it acts as a barrier to evaporation and also the shiny surface reflects heat and so lowers temperature.
• Sunken stomata: Stomata may be sunk in pits in the epidermis; moist air trapped here lengthens the diffusion pathway and reduces evaporation rate.

• Hydrophytes

• Plant adapted to live in extremely wet conditions. Common adaptations to increase the rate of gaseous exchange:
• Leaf Shape: The submerged leaves are often highly dissected or divided to create a very large surface area for absorption and photosynthesis. It also minimises water resistance and hence potential damage to the leaves. In many cases, the submerged leaves are totally different to floating or emergent leaves on the same plant. The emergent leaves are usually much less divided, if not entire and have a more similar internal structure to those of land plants.
• Lack of protective layer: The epidermal layer shows very little, if any, sign of cuticle formation, as water loss is not a problem. All the surface cells appear to be able to absorb water, nutrients and dissolved gases directly from the surrounding water. As a result, the xylem tubes is often greatly reduced, if not absent. *There are also no stomata on the underside of the leaves.

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Hydrophytes:

1. This include plants that live in water or wet conditions.

2. Leaves are large and broad.

3. These plants lack thick cuticle layer.

4. Stomata are present on the upper surface of leaf and are large in number.

Example: Water hyacinth.

Xerophytes:

1. This includes that live in dry conditions or Desert areas.

2. Leaves are small and spiny.

3. They have thick waxy cuticle.

4. Stomata are sunken in the pits of epidermis and are less in numbers.

Example: Cactus.

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Hydrophytes                                                                  Xerophytes

Plants adapted to grow in fresh water                             Plants adapted to grow in dry land

Large number of stomata on the upper leaf surface         Sunken stomata

Usually small roots                                                       deeper or wider root system

Eg:  Cactus                                                                Eg : water lilly

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hydrophytes are plants that grow only in water. eg. water lily

And xerophytes are plants that are adapted to grow in dry region. eg. cactus