The modifications in the structure of organisms to survive successfully in an environment are called adaptations of organisms. Adaptations help the organisms to exist under the prevailing ecological habitat. Based on the habitats and the corresponding adaptations of plants, they are classified as hydrophytes, xerophytes, mesophytes, epiphytes and halophytes.
Epiphytes are plants which grow perched on other plants (Supporting plants). They use the supporting plants only as shelter and not for water or food supply. These epiphytes are commonly seen in tropical rain forests. Examples: Orchids, Lianas, Hanging Mosses and Money plant.
• Root system is extensively developed. These roots may be of two types. They are Clinging roots and Aerial roots. Clinging roots fix the epiphytes firmly on the surface of the supporting objects. Aerial roots are green coloured roots which may hang downwardly and absorb moisture from the atmosphere with the help of a spongy tissue called velamen.
• Stem of some epiphytes are succulent and develop pseudobulb or tuber.
• Generally the leaves are lesser in number and may be fleshy and leathery
• Myrmecophily is a common occurrence in the epiphytic vegetation to prevent the predators.
• The fruits and seeds are very small and usually dispersed by wind, insects and birds.
Anatomical adaptations is
• Multilayered epidermis is present. Inner to the velamen tissue, the peculiar exodermis layer is present.
• Presence of thick cuticle and sunken stomata greatly reduces transpiration.
• Succulent epiphytes contain well developed parenchymatous cells to store water.
Physiological adaptations –
Special absorption processes of water by velamen tissue .