lichenforming

Lichenforming refers to the ability of certain fungi to form lichens through a symbiotic association with photosynthetic partners such as green algae or cyanobacteria. In this relationship, the fungal partner (the mycobiont) provides a protective thallus and a network of hyphae that enclose the photobiont cells, while the photosynthetic partner (the photobiont) supplies carbohydrates produced by photosynthesis. Cyanobacteria occur in some lichens and can contribute nitrogen, while green algae are more common in many crustose and foliose forms.

Lichen formation begins when a compatible photobiont becomes integrated into fungal tissues during early development. The resulting thallus takes on one of several growth forms, including crustose (crust-like), foliose (leafy), and fruticose (shrub-like). Asexual propagation can occur through structures such as soredia or isidia that contain both partners, enabling dispersal as a unit. Fungi can also reproduce sexually, producing diaspores that establish new lichen thalli with suitable photobionts.

Lichens are found in a wide range of environments, from bare rock to tree bark and soil, and play roles in ecological processes such as soil formation and nutrient cycling. They are often early colonizers in primary succession and are particularly valued as indicators of air quality due to their sensitivity to atmospheric pollutants. Lichen studies contribute to taxonomy, ecology, and natural product research, with lichenization describing the process by which a fungus becomes a lichen-forming partner in a symbiotic association.