Question

Give the economic importance of lichens

Answer 1

Hint: Lichens represents the symbiotic association of algae and fungi. Algae performs photosynthesis while fungi absorb water and raw materials needed by algae for photosynthesis.

Complete step by step answer:
The economic importance of lichens are:
a. Source of food- Cladonia rangiferina (Reindeer Moss) a fruticose lichen in the Arctic Tundra zone serves as food source for reindeer, caribou, musk ox, etc. The species of Parmelia is used as food in Southern India. Other edible species includesCetraria islandica (the Iceland moss) and Lecanora esculenta.
b. Source of dye- The lichens are used in the preparation of dyes like orchil (blue dye) to dye woollens. Litmus dye used in chemical laboratories as an acid-base indicator is obtained from Roccella montagnei.
c. Source of medicines: The species of lichen Peltigera camana, Lobaria pulmonaria, and Everina can cure jaundice, fevers, etc. & other ailments. Cetraria islandica (Iceland moss) mucilage product is used as a laxative.
d. They are the pioneer community in ecological succession.
e. They work as pollution indicators since they don’t grow in polluted regions.

Note: Lichens are associations of autotrophic algae and saprotrophic fungi. Algae lacks root, stem, and leaves. So they find it difficult to absorb minerals and water from soil. This limitation is overcome when algae associates with fungus. Fungus absorbs water, minerals from soil and provides it to algae to carry out photosynthesis. In return, algae provide food & shelter to the fungi. In this association, algae is termed as phycobionts while fungi are called mycobiont. Lichens are the first colony that invades the unhabituated area as a pioneer colony and helps in ecological succession.